Digitala Vetenskapliga Arkivet

Ändra sökning
Avgränsa sökresultatet
1234 1 - 50 av 177
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Ah-King, Malin
    et al.
    Stockholms universitet, Humanistiska fakulteten, Institutionen för etnologi, religionshistoria och genusvetenskap. Uppsala University, Sweden; University of California, USA.
    Gowaty, Patricia Adair
    A conceptual review of mate choice: stochastic demography, within-sex phenotypic plasticity, and individual flexibility2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 14, s. 4607-4642Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Mate choice hypotheses usually focus on trait variation of chosen individuals. Recently, mate choice studies have increasingly attended to the environmental circumstances affecting variation in choosers' behavior and choosers' traits. We reviewed the literature on phenotypic plasticity in mate choice with the goal of exploring whether phenotypic plasticity can be interpreted as individual flexibility in the context of the switch point theorem, SPT (Gowaty and Hubbell ). We found >3000 studies; 198 were empirical studies of within-sex phenotypic plasticity, and sixteen showed no evidence of mate choice plasticity. Most studies reported changes from choosy to indiscriminate behavior of subjects. Investigators attributed changes to one or more causes including operational sex ratio, adult sex ratio, potential reproductive rate, predation risk, disease risk, chooser's mating experience, chooser's age, chooser's condition, or chooser's resources. The studies together indicate that choosiness of potential mates is environmentally and socially labile, that is, induced - not fixed - in the choosy sex with results consistent with choosers' intrinsic characteristics or their ecological circumstances mattering more to mate choice than the traits of potential mates. We show that plasticity-associated variables factor into the simpler SPT variables. We propose that it is time to complete the move from questions about within-sex plasticity in the choosy sex to between- and within-individual flexibility in reproductive decision-making of both sexes simultaneously. Currently, unanswered empirical questions are about the force of alternative constraints and opportunities as inducers of individual flexibility in reproductive decision-making, and the ecological, social, and developmental sources of similarities and differences between individuals. To make progress, we need studies (1) of simultaneous and symmetric attention to individual mate preferences and subsequent behavior in both sexes, (2) controlled for within-individual variation in choice behavior as demography changes, and which (3) report effects on fitness from movement of individual's switch points.

  • 2.
    Ah-King, Malin
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Centrum för genusvetenskap. Dept Ecol & Evolutionary Biol, 621 Charles E Young Dr S, Los Angeles, CA 90095 USA.;Stockholm Univ, Dept Ethnol Hist Relig & Gender Studies, Univ Vagen 10 E, SE-10691 Stockholm, Sweden..
    Gowaty, Patricia Adair
    Dept Ecol & Evolutionary Biol, 621 Charles E Young Dr S, Los Angeles, CA 90095 USA.;Smithsonian Trop Res Inst, DPO, Box 0948,AA 34002-9998, Washington, DC USA.;Univ Calif Los Angeles, Inst Environm & Sustainabil, Los Angeles, CA 90095 USA..
    A conceptual review of mate choice: stochastic demography, within-sex phenotypic plasticity, and individual flexibility2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 14, s. 4607-4642Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Mate choice hypotheses usually focus on trait variation of chosen individuals. Recently, mate choice studies have increasingly attended to the environmental circumstances affecting variation in choosers' behavior and choosers' traits. We reviewed the literature on phenotypic plasticity in mate choice with the goal of exploring whether phenotypic plasticity can be interpreted as individual flexibility in the context of the switch point theorem, SPT (Gowaty and Hubbell ). We found >3000 studies; 198 were empirical studies of within-sex phenotypic plasticity, and sixteen showed no evidence of mate choice plasticity. Most studies reported changes from choosy to indiscriminate behavior of subjects. Investigators attributed changes to one or more causes including operational sex ratio, adult sex ratio, potential reproductive rate, predation risk, disease risk, chooser's mating experience, chooser's age, chooser's condition, or chooser's resources. The studies together indicate that choosiness of potential mates is environmentally and socially labile, that is, induced - not fixed - in the choosy sex with results consistent with choosers' intrinsic characteristics or their ecological circumstances mattering more to mate choice than the traits of potential mates. We show that plasticity-associated variables factor into the simpler SPT variables. We propose that it is time to complete the move from questions about within-sex plasticity in the choosy sex to between- and within-individual flexibility in reproductive decision-making of both sexes simultaneously. Currently, unanswered empirical questions are about the force of alternative constraints and opportunities as inducers of individual flexibility in reproductive decision-making, and the ecological, social, and developmental sources of similarities and differences between individuals. To make progress, we need studies (1) of simultaneous and symmetric attention to individual mate preferences and subsequent behavior in both sexes, (2) controlled for within-individual variation in choice behavior as demography changes, and which (3) report effects on fitness from movement of individual's switch points.

    Ladda ner fulltext (pdf)
    fulltext
  • 3.
    Alerstam, Thomas
    et al.
    Lund University.
    Bäckman, Johan
    Lund University.
    Johanna, Grönroos
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Olofsson, Patrik
    Heberg, Sweden.
    Strandberg, Roine
    Lund University.
    Hypotheses and tracking results about the longest migration: the case of the arctic tern2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The arctic tern Sterna paradisaea completes the longest known annual return migration on Earth, traveling between breeding sites in the northern arctic and temperate regions and survival/molt areas in the Antarctic pack‐ice zone. Salomonsen (1967, Biologiske Meddelelser, Copenhagen Danske Videnskabernes Selskab24, 1) put forward a hypothetical comprehensive interpretation of this global migration pattern, suggesting food distribution, wind patterns, sea ice distribution, and molt habits as key ecological and evolutionary determinants. We used light‐level geolocators to record 12 annual journeys by eight individuals of arctic terns breeding in the Baltic Sea. Migration cycles were evaluated in light of Salomonsen's hypotheses and compared with results from geolocator studies of arctic tern populations from Greenland, Netherlands, and Alaska. The Baltic terns completed a 50,000 km annual migration circuit, exploiting ocean regions of high productivity in the North Atlantic, Benguela Current, and the Indian Ocean between southern Africa and Australia (sometimes including the Tasman Sea). They arrived about 1 November in the Antarctic zone at far easterly longitudes (in one case even at the Ross Sea) subsequently moving westward across 120–220 degrees of longitude toward the Weddell Sea region. They departed from here in mid‐March on a fast spring migration up the Atlantic Ocean. The geolocator data revealed unexpected segregation in time and space between tern populations in the same flyway. Terns from the Baltic and Netherlands traveled earlier and to significantly more easterly longitudes in the Indian Ocean and Antarctic zone than terns from Greenland. We suggest an adaptive explanation for this pattern. The global migration system of the arctic tern offers an extraordinary possibility to understand adaptive values and constraints in complex pelagic life cycles, as determined by environmental conditions (marine productivity, wind patterns, low‐pressure trajectories, pack‐ice distribution), inherent factors (flight performance, molt, flocking), and effects of predation/piracy and competition.

    Ladda ner fulltext (pdf)
    fulltext
  • 4.
    Arct, Aneta
    et al.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland.
    Drobniak, Szymon M.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland.
    Mellinger, Samantha
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland.
    Gustafsson, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Cichon, Mariusz
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland.
    Parental genetic similarity and offspring performance in blue tits in relation to brood size manipulation2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 18, s. 10085-10091Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In birds, as in many other taxa, higher genetic similarity of mates has long been known to reduce offspring fitness. To date, the majority of avian studies have focused on examination whether the genetic similarity of social mates predicts hatching success. Yet, increased genetic similarity of mates may also reduce offspring fitness during later life stages, including the nestling period and beyond. Here, we investigated whether parental genetic similarity influences offspring performance using data from free-living blue tits (Cyanistes caeruleus) collected across three breeding seasons. Additionally, we tested whether brood size manipulation affects the magnitude and direction of the relationship between genetic similarity of mates and offspring performance. Sixteen microsatellite markers were used to measure genetic similarity between biological parents. We found that the genetic similarity of parents negatively affects offspring immune response and this effect was independent of the experimental brood size manipulation.

    Ladda ner fulltext (pdf)
    fulltext
  • 5.
    Ardalan, Arman
    et al.
    KTH, Skolan för bioteknologi (BIO), Genteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Kluetsch, Cornelya F. C.
    KTH, Centra, Science for Life Laboratory, SciLifeLab. KTH, Skolan för bioteknologi (BIO), Genteknologi.
    Zhang, Ai-bing
    KTH, Skolan för bioteknologi (BIO), Genteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Erdogan, Metin
    Uhlén, Mathias
    KTH, Skolan för bioteknologi (BIO), Proteomik (stängd 20130101).
    Houshmand, Massoud
    Tepeli, Cafer
    Ashtiani, Seyed Reza Miraei
    Savolainen, Peter
    KTH, Skolan för bioteknologi (BIO), Genteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Comprehensive study of mtDNA among Southwest Asian dogs contradicts independent domestication of wolf, but implies dog–wolf hybridization2011Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 1, nr 3, s. 373-385Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Studies of mitochondrial DNA (mtDNA) diversity indicate explicitly that dogs were domesticated, probably exclusively, in southern East Asia. However, Southwest Asia (SwAsia) has had poor representation and geographical coverage in these studies. Other studies based on archaeological and genome-wide SNP data have suggested an origin of dogs in SwAsia. Hence, it has been suspected that mtDNA evidence for this scenario may have remained undetected. In the first comprehensive investigation of genetic diversity among SwAsian dogs, we analyzed 582 bp of mtDNA for 345 indigenous dogs from across SwAsia, and compared with 1556 dogs across the Old World. We show that 97.4% of SwAsian dogs carry haplotypes belonging to a universal mtDNA gene pool, but that only a subset of this pool, five of the 10 principal haplogroups, is represented in SwAsia. A high frequency of haplogroup B, potentially signifying a local origin, was not paralleled with the high genetic diversity expected for a center of origin. Meanwhile, 2.6% of the SwAsian dogs carried the rare non-universal haplogroup d2. Thus, mtDNA data give no indication that dogs originated in SwAsia through independent domestication of wolf, but dog–wolf hybridization may have formed the local haplogroup d2 within this region. Southern East Asia remains the only region with virtually full extent of genetic variation, strongly indicating it to be the primary and probably sole center of wolf domestication. An origin of dogs in southern East Asia may have been overlooked by other studies due to a substantial lack of samples from this region.

  • 6. Ardehed, Angelica
    et al.
    Johansson, Daniel
    Schagerström, Ellen
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Kautsky, Lena
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Johannesson, Kerstin
    Pereyra, Ricardo T.
    Complex spatial clonal structure in the macroalgae Fucus radicans with both sexual and asexual recruitment2015Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 5, nr 19, s. 4233-4245Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In dioecious species with both sexual and asexual reproduction, the spatial distribution of individual clones affects the potential for sexual reproduction and local adaptation. The seaweed Fucus radicans, endemic to the Baltic Sea, has separate sexes, but new attached thalli may also form asexually. We mapped the spatial distribution of clones (multilocus genotypes, MLGs) over macrogeographic (>500km) and microgeographic (<100m) scales in the Baltic Sea to assess the relationship between clonal spatial structure, sexual recruitment, and the potential for natural selection. Sexual recruitment was predominant in some areas, while in others asexual recruitment dominated. Where clones of both sexes were locally intermingled, sexual recruitment was nevertheless low. In some highly clonal populations, the sex ratio was strongly skewed due to dominance of one or a few clones of the same sex. The two largest clones (one female and one male) were distributed over 100-550km of coast and accompanied by small and local MLGs formed by somatic mutations and differing by 1-2 mutations from the large clones. Rare sexual events, occasional long-distance migration, and somatic mutations contribute new genotypic variation potentially available to natural selection. However, dominance of a few very large (and presumably old) clones over extensive spatial and temporal scales suggested that either these have superior traits or natural selection has only been marginally involved in the structuring of genotypes.

  • 7. Astor, Tina
    et al.
    Strengbom, Joachim
    Berg, Matty P.
    Lenoir, Lisette
    Marteinsdottir, Bryndis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Bengtsson, Jan
    Underdispersion and overdispersion of traits in terrestrial snail communities on islands2014Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 4, nr 11, s. 2090-2102Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding and disentangling different processes underlying the assembly and diversity of communities remains a key challenge in ecology. Species can assemble into communities either randomly or due to deterministic processes. Deterministic assembly leads to species being more similar (underdispersed) or more different (overdispersed) in certain traits than would be expected by chance. However, the relative importance of those processes is not well understood for many organisms, including terrestrial invertebrates. Based on knowledge of a broad range of species traits, we tested for the presence of trait underdispersion (indicating dispersal or environmental filtering) and trait overdispersion (indicating niche partitioning) and their relative importance in explaining land snail community composition on lake islands. The analysis of community assembly was performed using a functional diversity index (Rao's quadratic entropy) in combination with a null model approach. Regression analysis with the effect sizes of the assembly tests and environmental variables gave information on the strength of under- and overdispersion along environmental gradients. Additionally, we examined the link between community weighted mean trait values and environmental variables using a CWM-RDA. We found both trait underdispersion and trait overdispersion, but underdispersion (eight traits) was more frequently detected than overdispersion (two traits). Underdispersion was related to four environmental variables (tree cover, habitat diversity, productivity of ground vegetation, and location on an esker ridge). Our results show clear evidence for underdispersion in traits driven by environmental filtering, but no clear evidence for dispersal filtering. We did not find evidence for overdispersion of traits due to diet or body size, but overdispersion in shell shape may indicate niche differentiation between snail species driven by small-scale habitat heterogeneity. The use of species traits enabled us to identify key traits involved in snail community assembly and to detect the simultaneous occurrence of trait underdispersion and overdispersion.

  • 8.
    Audusseau, Helene
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Nylin, Sören
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Janz, Niklas
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Implications of a temperature increase for host plant range: predictions for a butterfly2013Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 3, nr 9, s. 3021-3029Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although changes in phenology and species associations are relatively well-documented responses to global warming, the potential interactions between these phenomena are less well understood. In this study, we investigate the interactions between temperature, phenology (in terms of seasonal timing of larval growth) and host plant use in the polyphagous butterfly Polygonia c-album. We found that the hierarchy of larval performance on three natural host plants was not modified by a temperature increase as such. However, larval performance on each host plant and temperature treatment was affected by rearing season. Even though larvae performed better at the higher temperature regardless of the time of the rearing, relative differences between host plants changed with the season. For larvae reared late in the season, performance was always better on the herbaceous plant than on the woody plants. In this species, it is likely that a prolonged warming will lead to a shift from univoltinism to bivoltinism. The demonstrated interaction between host plant suitability and season means that such a shift is likely to lead to a shift in selective regime, favoring specialization on the herbaceous host. Based on our result, we suggest that host range evolution in response to temperature increase would in this species be highly contingent on whether the population undergoes a predicted shift from one to two generations. We discuss the effect of global warming on species associations and the outcome of asynchrony in rates of phenological change.

  • 9.
    Backström, Niclas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Shipilina, Daria
    Bloom, Mozes
    Edwards, Scott
    Cis-regulatory sequence variation and association with Mycoplasma load in natural populations of the house finch (Carpodacus mexicanus)2013Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 3, nr 3, s. 655-666Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Characterization of the genetic basis of fitness traits in natural populations is important for understanding how organisms adapt to the changing environment and to novel events, such as epizootics. However, candidate fitness-influencing loci, such as regulatory regions, are usually unavailable in nonmodel species. Here, we analyze sequence data from targeted resequencing of the cis-regulatory regions of three candidate genes for disease resistance (CD74, HSP90α, and LCP1) in populations of the house finch (Carpodacus mexicanus) historically exposed (Alabama) and naïve (Arizona) to Mycoplasma gallisepticum. Our study, the first to quantify variation in regulatory regions in wild birds, reveals that the upstream regions of CD74 and HSP90α are GC-rich, with the former exhibiting unusually low sequence variation for this species. We identified two SNPs, located in a GC-rich region immediately upstream of an inferred promoter site in the gene HSP90α, that were significantly associated with Mycoplasma pathogen load in the two populations. The SNPs are closely linked and situated in potential regulatory sequences: one in a binding site for the transcription factor nuclear NFYα and the other in a dinucleotide microsatellite ((GC)6). The genotype associated with pathogen load in the putative NFYα binding site was significantly overrepresented in the Alabama birds. However, we did not see strong effects of selection at this SNP, perhaps because selection has acted on standing genetic variation over an extremely short time in a highly recombining region. Our study is a useful starting point to explore functional relationships between sequence polymorphisms, gene expression, and phenotypic traits, such as pathogen resistance that affect fitness in the wild.

  • 10. Barboza, Francisco R.
    et al.
    Kotta, Jonne
    Weinberger, Florian
    Jormalainen, Veijo
    Kraufvelin, Patrik
    Molis, Markus
    Schubert, Hendrik
    Pavia, Henrik
    Nylund, Göran M.
    Kautsky, Lena
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholms universitets Östersjöcentrum.
    Schagerström, Ellen
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Rickert, Esther
    Saha, Mahasweta
    Fredriksen, Stein
    Martin, Georg
    Torn, Kaire
    Ruuskanen, Ari
    Wahl, Martin
    Geographic variation in fitness-related traits of the bladderwrack Fucus vesiculosus along the Baltic Sea-North Sea salinity gradient2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 16, s. 9225-9238Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the course of the ongoing global intensification and diversification of human pressures, the study of variation patterns of biological traits along environmental gradients can provide relevant information on the performance of species under shifting conditions. The pronounced salinity gradient, co-occurrence of multiple stressors, and accelerated rates of change make the Baltic Sea and its transition to North Sea a suitable region for this type of study. Focusing on the bladderwrack Fucus vesiculosus, one of the main foundation species on hard-bottoms of the Baltic Sea, we analyzed the phenotypic variation among populations occurring along 2,000 km of coasts subjected to salinities from 4 to >30 and a variety of other stressors. Morphological and biochemical traits, including palatability for grazers, were recorded at 20 stations along the Baltic Sea and four stations in the North Sea. We evaluated in a common modeling framework the relative contribution of multiple environmental drivers to the observed trait patterns. Salinity was the main and, in some cases, the only environmental driver of the geographic trait variation in F. vesiculosus. The decrease in salinity from North Sea to Baltic Sea stations was accompanied by a decline in thallus size, photosynthetic pigments, and energy storage compounds, and affected the interaction of the alga with herbivores and epibiota. For some traits, drivers that vary locally such as wave exposure, light availability or nutrient enrichment were also important. The strong genetic population structure in this macroalgae might play a role in the generation and maintenance of phenotypic patterns across geographic scales. In light of our results, the desalination process projected for the Baltic Sea could have detrimental impacts on F. vesiculosus in areas close to its tolerance limit, affecting ecosystem functions such as habitat formation, primary production, and food supply.

  • 11.
    Bengtsson, Fia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Granath, Gustaf
    Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Rydin, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Photosynthesis, growth, and decay traits in Sphagnum – a multispecies comparison2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 10, s. 3325-3341Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Peat mosses (Sphagnum) largely govern carbon sequestration in Northern Hemisphere peatlands. We investigated functional traits related to growth and decomposition in Sphagnum species. We tested the importance of environment and phylogeny in driving species traits and investigated trade-offs among them. We selected 15 globally important Sphagnum species, representing four sections (subgenera) and a range of peatland habitats. We measured rates of photosynthesis and decomposition in standard laboratory conditions as measures of innate growth and decay potential, and related this to realized growth, production, and decomposition in their natural habitats. In general, we found support for a trade-off between measures of growth and decomposition. However, the relationships are not strong, with r ranging between 0.24 and 0.45 for different measures of growth versus decomposition. Using photosynthetic rate to predict decomposition in standard conditions yielded R2 = 0.20. Habitat and section (phylogeny) affected the traits and the trade-offs. In a wet year, species from sections Cuspidata and Sphagnum had the highest production, but in a dry year, differences among species, sections, and habitats evened out. Cuspidata species in general produced easily decomposable litter, but their decay in the field was hampered, probably due to near-surface anoxia in their wet habitats. In a principal components analysis, PCA, photosynthetic capacity, production, and laboratory decomposition acted in the same direction. The species were imperfectly clustered according to vegetation type and phylogeny, so that some species clustered with others in the same section, whereas others clustered more clearly with others from similar vegetation types. Our study includes a wider range of species and habitats than previous trait analyses in Sphagnum and shows that while the previously described growth–decay trade-off exists, it is far from perfect. We therefore suggest that our species-specific trait measures offer opportunities for improvements of peatland ecosystem models. Innate qualities measured in laboratory conditions translate differently to field responses. Most dramatically, fast-growing species could only realize their potential in a wet year. The same species decompose fast in laboratory, but their decomposition was more retarded in the field than that of other species. These relationships are crucial for understanding the long-term dynamics of peatland communities.

    Ladda ner fulltext (pdf)
    fulltext
  • 12.
    Bianco, Giuseppe
    et al.
    Lund University, Sweden.
    Ilieva, Mihaela
    Lund University, Sweden; Bulgarian Academic Science, Bulgaria.
    Veibäck, Clas
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Öfjäll, Kristoffer
    Linköpings universitet, Institutionen för systemteknik, Datorseende. Linköpings universitet, Tekniska fakulteten.
    Gadomska, Alicja
    Lund University, Sweden.
    Hendeby, Gustaf
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Felsberg, Michael
    Linköpings universitet, Institutionen för systemteknik, Datorseende. Linköpings universitet, Tekniska fakulteten.
    Gustafsson, Fredrik
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Åkesson, Susanne
    Lund University, Sweden.
    Emlen funnel experiments revisited: methods update for studying compass orientation in songbirds2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 19, s. 6930-6942Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    1 Migratory songbirds carry an inherited capacity to migrate several thousand kilometers each year crossing continental landmasses and barriers between distant breeding sites and wintering areas. How individual songbirds manage with extreme precision to find their way is still largely unknown. The functional characteristics of biological compasses used by songbird migrants has mainly been investigated by recording the birds directed migratory activity in circular cages, so-called Emlen funnels. This method is 50 years old and has not received major updates over the past decades. The aim of this work was to compare the results from newly developed digital methods with the established manual methods to evaluate songbird migratory activity and orientation in circular cages. 2 We performed orientation experiments using the European robin (Erithacus rubecula) using modified Emlen funnels equipped with thermal paper and simultaneously recorded the songbird movements from above. We evaluated and compared the results obtained with five different methods. Two methods have been commonly used in songbirds orientation experiments; the other three methods were developed for this study and were based either on evaluation of the thermal paper using automated image analysis, or on the analysis of videos recorded during the experiment. 3 The methods used to evaluate scratches produced by the claws of birds on the thermal papers presented some differences compared with the video analyses. These differences were caused mainly by differences in scatter, as any movement of the bird along the sloping walls of the funnel was recorded on the thermal paper, whereas video evaluations allowed us to detect single takeoff attempts by the birds and to consider only this behavior in the orientation analyses. Using computer vision, we were also able to identify and separately evaluate different behaviors that were impossible to record by the thermal paper. 4 The traditional Emlen funnel is still the most used method to investigate compass orientation in songbirds under controlled conditions. However, new numerical image analysis techniques provide a much higher level of detail of songbirds migratory behavior and will provide an increasing number of possibilities to evaluate and quantify specific behaviors as new algorithms will be developed.

    Ladda ner fulltext (pdf)
    fulltext
  • 13. Birkhofer, Klaus
    et al.
    Bylund, Helena
    Dalin, Peter
    Ferlian, Olga
    Gagic, Vesna
    Hambäck, Peter A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Klapwijk, Maartje
    Mestre, Laia
    Roubinet, Eve
    Schroeder, Martin
    Stenberg, Johan A.
    Porcel, Mario
    Björkman, Christer
    Jonsson, Mattias
    Methods to identify the prey of invertebrate predators in terrestrial field studies2017Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 7, nr 6, s. 1942-1953Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Predation is an interaction during which an organism kills and feeds on another organism. Past and current interest in studying predation in terrestrial habitats has yielded a number of methods to assess invertebrate predation events in terrestrial ecosystems. We provide a decision tree to select appropriate methods for individual studies. For each method, we then present a short introduction, key examples for applications, advantages and disadvantages, and an outlook to future refinements. Video and, to a lesser extent, live observations are recommended in studies that address behavioral aspects of predator-prey interactions or focus on per capita predation rates. Cage studies are only appropriate for small predator species, but often suffer from a bias via cage effects. The use of prey baits or analyses of prey remains are cheaper than other methods and have the potential to provide per capita predation estimates. These advantages often come at the cost of low taxonomic specificity. Molecular methods provide reliable estimates at a fine level of taxonomic resolution and are free of observer bias for predator species of any size. However, the current PCR-based methods lack the ability to estimate predation rates for individual predators and are more expensive than other methods. Molecular and stable isotope analyses are best suited to address systems that include a range of predator and prey species. Our review of methods strongly suggests that while in many cases individual methods are sufficient to study specific questions, combinations of methods hold a high potential to provide more holistic insights into predation events. This review presents an overview of methods to researchers that are new to the field or to particular aspects of predation ecology and provides recommendations toward the subset of suitable methods to identify the prey of invertebrate predators in terrestrial field research.

  • 14.
    Bischof, Richard
    et al.
    Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, Hogskoleveien 12, N-1430 As, Norway..
    Gregersen, Espen R.
    Norwegian Univ Life Sci, Dept Ecol & Nat Resource Management, Hogskoleveien 12, N-1430 As, Norway..
    Broseth, Henrik
    Norwegian Inst Nat Res, Tungasletta 2, N-7004 Trondheim, Norway..
    Ellegren, Hans
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Flagstad, Oystein
    Norwegian Inst Nat Res, Tungasletta 2, N-7004 Trondheim, Norway..
    Noninvasive genetic sampling reveals intrasex territoriality in wolverines2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 5, s. 1527-1536Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to its conspicuous manifestations and its capacity to shape the configuration and dynamics of wild populations, territorial behavior has long intrigued ecologists. Territoriality and other animal interactions in situ have traditionally been studied via direct observations and telemetry. Here, we explore whether noninvasive genetic sampling, which is increasingly supplementing traditional field methods in ecological research, can reveal territorial behavior in an elusive carnivore, the wolverine (Gulo gulo). Using the locations of genotyped wolverine scat samples collected annually over a period of 12 years in central Norway, we test three predictions: (1) male home ranges constructed from noninvasive genetic sampling data are larger than those of females, (2) individuals avoid areas used by other conspecifics of the same sex (intrasexual territoriality), and (3) avoidance of same-sex territories diminishes or disappears after the territory owner's death. Each of these predictions is substantiated by our results: sex-specific differences in home range size and intrasexual territoriality in wolverine are patently reflected in the spatial and temporal configuration of noninvasively collected genetic samples. Our study confirms that wildlife monitoring programs can utilize the spatial information in noninvasive genetic sampling data to detect and quantify home ranges and social organization.

    Ladda ner fulltext (pdf)
    fulltext
  • 15.
    Björklund, Mats
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Aho, Teija
    Behrmann-Godel, Jasminca
    Isolation over 35 years in a heated biotest basin causes selection on MHC class II beta genes in the European perch (Perca fluviatilis L.)2015Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 5, nr 7, s. 1440-1455Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Genes that play key roles in host immunity such as the major histocompatibility complex (MHC) in vertebrates are expected to be major targets of selection. It is well known that environmental conditions can have an effect on host-parasite interactions and may thus influence the selection on MHC. We analyzed MHC class II ss variability over 35years in a population of perch (Perca fluviatilis) from the Baltic Sea that was split into two populations separated from each other. One population was subjected to heating from cooling water of a nuclear power plant and was isolated from the surrounding environment in an artificial lake, while the other population was not subjected to any change in water temperature (control). The isolated population experienced a change of the allelic composition and a decrease in allelic richness of MHC genes compared to the control population. The two most common MHC alleles showed cyclic patterns indicating ongoing parasite-host coevolution in both populations, but the alleles that showed a cyclic behavior differed between the two populations. No such patterns were observed at alleles from nine microsatellite loci, and no genetic differentiation was found between populations. We found no indications for a genetic bottleneck in the isolated population during the 35years. Additionally, differences in parasitism of the current perch populations suggest that a change of the parasite communities has occurred over the isolation period, although the evidence in form of in-depth knowledge of the change of the parasite community over time is lacking. Our results are consistent with the hypothesis of a selective sweep imposed by a change in the parasite community.

    Ladda ner fulltext (pdf)
    fulltext
  • 16.
    Björklund, Mats
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Borras, Antoni
    Cabrera, Josep
    Senar, Juan Carlos
    Increase in body size is correlated to warmer winters in a passerine bird as inferred from time series data2015Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 5, nr 1, s. 59-72Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Climate change is expected to affect natural populations in many ways. One way of getting an understanding of the effects of a changing climate is to analyze time series of natural populations. Therefore, we analyzed time series of 25 and 20years, respectively, in two populations of the citril finch (Carduelis citrinella) to understand the background of a dramatic increase in wing length in this species over this period, ranging between 1.3 and 2.9 phenotypic standard deviations. We found that the increase in wing length is closely correlated to warmer winters and in one case to rain in relation to temperature in the summer. In order to understand the process of change, we implemented seven simulation models, ranging from two nonadaptive models (drift and sampling), and five adaptive models with selection and/or phenotypic plasticity involved and tested these models against the time series of males and females from the two population separately. The nonadaptive models were rejected in each case, but the results were mixed when it comes to the adaptive models. The difference in fit of the models was sometimes not significant indicating that the models were not different enough. In conclusion, the dramatic change in mean wing length can best be explained as an adaptive response to a changing climate.

    Ladda ner fulltext (pdf)
    fulltext
  • 17.
    Björklund, Mats
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Gustafsson, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    The importance of selection at the level of the pair over 25 years in a natural population of birds2013Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 3, nr 13, s. 4610-4619Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Knowledge of the pattern of selection in natural populations is fundamental for our understanding of the evolutionary process. Selection at higher levels has gained considerable theoretical support in recent years, and one possible level of selection is the breeding pair where fitness is a function of the pair and cannot be reduced to single individuals. We analyzed the importance of pair-level selection over 25years in a natural population of the collared flycatcher. Pair-level selection was significant in five and probably in another 9years. The relative importance of pair-level selection varied over years and can have stronger or the same strength as directional selection. This means that selection can act on the combination of the breeding pair in addition to selection on each individual separately. Overall, the conservative estimates obtained here show that this is a potentially important form of selection.

    Ladda ner fulltext (pdf)
    fulltext
  • 18.
    Bodare, Sofia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för evolution, genomik och systematik, Evolutionär funktionsgenomik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Stocks, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Yang, J-C
    Taiwan Forestry Research Institute.
    Lascoux, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Origin and demographic history of the endemic Taiwan spruce (Picea morrisonicola)2013Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 3, nr 10, s. 3320-3333Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Taiwan spruce (Picea morrisonicola) is a vulnerable conifer species endemic to the island of Taiwan. A warming climate and competition from subtropical tree species has limited the range of Taiwan spruce to the higher altitudes of the island. Using seeds sampled from an area in the central mountain range of Taiwan, 15 nuclear loci were sequenced in order to measure genetic variation and to assess the long-term genetic stability of the species. Genetic diversity is low and comparable to other spruce species with limited ranges such as Picea breweriana, Picea chihuahuana, and Picea schrenkiana. Importantly, analysis using approximate Bayesian computation (ABC) provides evidence for a drastic decline in the effective population size approximately 0.3–0.5 million years ago (mya). We used simulations to show that this is unlikely to be a false-positive result due to the limited sample used here. To investigate the phylogenetic origin of Taiwan spruce, additional sequencing was performed in the Chinese spruce Picea wilsonii and combined with previously published data for three other mainland China species, Picea purpurea, Picea likiangensis, and P. schrenkiana. Analysis of population structure revealed that P. morrisonicola clusters most closely with P. wilsonii, and coalescent analyses using the program MIMAR dated the split to 4–8 mya, coincidental to the formation of Taiwan. Considering the population decrease that occurred after the split, however, led to a much more recent origin.

  • 19.
    Bodare, Sofia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Tsuda, Yoshiaki
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ravikanth, G
    Ashoka Trust for Research in Ecology and the Environment.
    Uma Shaanker, R
    Ashoka Trust for Research in Ecology and the Environment.
    Lascoux, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Genetic structure and demographic history of the endangered tree species, Dysoxylum  malabaricum (Meliaceae) in Western Ghats, India: Implications for conservation in a  biodiversity hotspot2013Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 3, nr 10, s. 3233-3248Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    The impact of fragmentation by human activities on genetic diversity of forest trees is an important concern in forest conservation, especially in tropical forests. Dysoxylummalabaricum (white cedar) is an economically important tree species, endemic to theWestern Ghats, India, one of the world's eight most important biodiversity hotspots. As D.malabaricum is under pressure of disturbance and fragmentation together with overharvesting, conservation efforts are required in this species. In this study, range-widegenetic structure of twelve D.malabaricum populations was evaluated to assess the impact ofhuman activities on genetic diversity and infer the species' evolutionary history, using both nuclear and chloroplast (cp) DNA simple sequence repeats (SSR). As genetic diversity and population structure did not differ among seedling, juvenile and adult age classes, reproductive success among the old-growth trees and long distance seed dispersal by hornbills were suggested to contribute to maintain genetic diversity. The fixation index (F-IS) was significantly correlated with latitude, with a higher level of inbreeding in the northern populations, possibly reflecting a more severe ecosystem disturbance in those populations. Both nuclear and cpSSRs revealed northern and southern genetic groups with some discordance of their distributions; however, they did not correlate with any of the two geographic gaps known as genetic barriers to animals. Approximate Bayesian computation-based inference from nuclear SSRs suggested that population divergence occurred beforethe last glacial maximum. Finally we discussed the implications of these results, in particularthe presence of a clear pattern of historical genetic subdivision, on conservation policies.

  • 20. Calboli, Federico C. F.
    et al.
    Byström, Pär
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Merila, Juha
    A test for within-lake niche differentiation in the nine-spined sticklebacks (Pungitius pungitius)2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 14, s. 4753-4760Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Specialization for the use of different resources can lead to ecological speciation. Accordingly, there are numerous examples of ecologically specialized pairs of fish species in postglacial lakes. Using a polymorphic panel of single nucleotide variants, we tested for genetic footprints of within-lake population stratification in nine-spined sticklebacks (Pungitius pungitius) collected from three habitats (viz. littoral, benthic, and pelagic) within a northern Swedish lake. Analyses of admixture, population structure, and relatedness all supported the conclusion that the fish from this lake form a single interbreeding unit.

    Ladda ner fulltext (pdf)
    fulltext
  • 21. Campbell-Staton, Shane C
    et al.
    Goodman, Rachel M
    Backström, Niclas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Edwards, Scott V
    Losos, Jonathan B
    Kolbe, Jason J
    Out of Florida: mtDNA reveals patterns of migration and Pleistocene range expansion of the Green Anole lizard (Anolis carolinensis).2012Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 2, nr 9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Anolis carolinensis is an emerging model species and the sole member of its genus native to the United States. Considerable morphological and physiological variation has been described in the species, and the recent sequencing of its genome makes it an attractive system for studies of genome variation. To inform future studies of molecular and phenotypic variation within A. carolinensis, a rigorous account of intraspecific population structure and relatedness is needed. Here, we present the most extensive phylogeographic study of this species to date. Phylogenetic analyses of mitochondrial DNA sequence data support the previous hypothesis of a western Cuban origin of the species. We found five well-supported, geographically distinct mitochondrial haplotype clades throughout the southeastern United States. Most Florida populations fall into one of three divergent clades, whereas the vast majority of populations outside Florida belong to a single, shallowly diverged clade. Genetic boundaries do not correspond to major rivers, but may reflect effects of Pleistocene glaciation events and the Appalachian Mountains on migration and expansion of the species. Phylogeographic signal should be examined using nuclear loci to complement these findings.

  • 22. Carlos Senar, Juan
    et al.
    Conroy, Michael J.
    Quesada, Javier
    Mateos-Gonzalez, Fernando
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Selection based on the size of the black tie of the great tit may be reversed in urban habitats2014Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 4, nr 13, s. 2625-2632Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A standard approach to model how selection shapes phenotypic traits is the analysis of capture-recapture data relating trait variation to survival. Divergent selection, however, has never been analyzed by the capture-recapture approach. Most reported examples of differences between urban and nonurban animals reflect behavioral plasticity rather than divergent selection. The aim of this paper was to use a capture-recapture approach to test the hypothesis that divergent selection can also drive local adaptation in urban habitats. We focused on the size of the black breast stripe (i.e., tie width) of the great tit (Parus major), a sexual ornament used in mate choice. Urban great tits display smaller tie sizes than forest birds. Because tie size is mostly genetically determined, it could potentially respond to selection. We analyzed capture/recapture data of male great tits in Barcelona city (N = 171) and in a nearby (7 km) forest (N = 324) from 1992 to 2008 using MARK. When modelling recapture rate, we found it to be strongly influenced by tie width, so that both for urban and forest habitats, birds with smaller ties were more trap-shy and more cautious than their larger tied counterparts. When modelling survival, we found that survival prospects in forest great tits increased the larger their tie width (i.e., directional positive selection), but the reverse was found for urban birds, with individuals displaying smaller ties showing higher survival (i.e., directional negative selection). As melanin-based tie size seems to be related to personality, and both are heritable, results may be explained by cautious personalities being favored in urban environments. More importantly, our results show that divergent selection can be an important mechanism in local adaptation to urban habitats and that capture-recapture is a powerful tool to test it.

    Ladda ner fulltext (pdf)
    fulltext
  • 23. Collin, Helene
    et al.
    Burri, Reto
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Comtesse, Fabien
    Fumagalli, Luca
    Combining molecular evolution and environmental genomics to unravel adaptive processes of MHC class IIB diversity in European minnows (Phoxinus phoxinus)2013Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 3, nr 8, s. 2568-2585Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Host-pathogen interactions are a major evolutionary force promoting local adaptation. Genes of the major histocompatibility complex (MHC) represent unique candidates to investigate evolutionary processes driving local adaptation to parasite communities. The present study aimed at identifying the relative roles of neutral and adaptive processes driving the evolution of MHC class IIB (MHCIIB) genes in natural populations of European minnows (Phoxinus phoxinus). To this end, we isolated and genotyped exon 2 of two MHCIIB gene duplicates (DAB1 and DAB3) and 1665 amplified fragment length polymorphism (AFLP) markers in nine populations, and characterized local bacterial communities by 16S rDNA barcoding using 454 amplicon sequencing. Both MHCIIB loci exhibited signs of historical balancing selection. Whereas genetic differentiation exceeded that of neutral markers at both loci, the populations' genetic diversities were positively correlated with local pathogen diversities only at DAB3. Overall, our results suggest pathogen-mediated local adaptation in European minnows at both MHCIIB loci. While at DAB1 selection appears to favor different alleles among populations, this is only partially the case in DAB3, which appears to be locally adapted to pathogen communities in terms of genetic diversity. These results provide new insights into the importance of host-pathogen interactions in driving local adaptation in the European minnow, and highlight that the importance of adaptive processes driving MHCIIB gene evolution may differ among duplicates within species, presumably as a consequence of alternative selective regimes or different genomic context.

  • 24.
    Cui, Qiao-Yu
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Gaillard, Marie-José
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Lemdahl, Geoffrey
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Stenberg, Li
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Lund University.
    Sugita, Shinya
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Tallinn University, Estonia.
    Zernova, Ganna
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Historical land-use and landscape change in southern Sweden and implications for present and future biodiversity2014Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 4, nr 18, s. 3555-3570Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The two major aims of this study are (1) To test the performance of the Landscape Reconstruction Algorithm (LRA) to quantify past landscape changes using historical maps and related written sources, and (2) to use the LRA and map reconstructions for a better understanding of the origin of landscape diversity and the recent loss of species diversity. Southern Sweden, hemiboreal vegetation zone. The LRA was applied on pollen records from three small bogs for four time windows between AD 1700 and 2010. The LRA estimates of % cover for woodland/forest, grassland, wetland, and cultivated land were compared with those extracted from historical maps within 3-km radius around each bog. Map-extracted land-use categories and pollen-based LRA estimates (in % cover) of the same land-use categories show a reasonable agreement in several cases; when they do not agree, the assumptions used in the data (maps)-model (LRA) comparison are a better explanation of the discrepancies between the two than possible biases of the LRA modeling approach. Both the LRA reconstructions and the historical maps reveal between-site differences in landscape characteristics through time, but they demonstrate comparable, profound transformations of the regional and local landscapes over time and space due to the agrarian reforms in southern Sweden during the 18th and 19th centuries. The LRA was found to be the most reasonable approach so far to reconstruct quantitatively past landscape changes from fossil pollen data. The existing landscape diversity in the region at the beginning of the 18th century had its origin in the long-term regional and local vegetation and land-use history over millennia. Agrarian reforms since the 18th century resulted in a dramatic loss of landscape diversity and evenness in both time and space over the last two centuries leading to a similarly dramatic loss of species (e.g., beetles).

  • 25.
    Cunha, Mario
    et al.
    CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal.
    Macedo, Nidia
    CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal.
    Wilson, Jonathan
    CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Porto, Portugal; Wilfrid Laurier University, Waterloo, Ontario, Canada.
    Rosenqvist, Gunilla
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Naturresurser och hållbar utveckling. Department of Biology, CBD, NTNU, Trondheim, Norway.
    Berglund, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Monteiro, Nuno
    CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal; Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal; Faculdade de Ciências da Saúde, CEBIMED, Universidade Fernando Pessoa, Porto, Portugal.
    Reduced sexual size dimorphism in a pipefish population where males do not prefer larger females2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 22, s. 12826-12835Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Within a species' distribution, populations are often exposed to diverse environmentsand may thus experience different sources of both natural and sexual selection.These differences are likely to impact the balance between costs and benefits toindividuals seeking reproduction, thus entailing evolutionary repercussions. Here, welook into an unusual population (Baltic Sea) of the broadnosed pipefish, Syngnathustyphle, where males do not seem to select females based on size and hypothesizethat this pattern may derive from a reduction in direct benefits to the male. We furtherhypothesize that if larger females do not persistently secure a higher reproductivesuccess, either through pre‐ or postcopulatory sexual selection, a decrease insexual size dimorphism in the Baltic population should be apparent, especially whencontrasted with a well‐studied population, inhabiting similar latitudes (Swedish westcoast), where males prefer larger females. We found that, in the Baltic population,variation in female quality is low. We were unable to find differences in abortion ratesor protein concentration in oocytes produced by females of contrasting sizes. Directbenefits from mating with large partners seem, thus, reduced in the Baltic population.We also found no evidence of any postcopulatory mechanism that could favorlarger mothers as embryo development was unrelated to female size. While femalesize can still be selected through intrasexual competition or fecundity selection, thepressure for large female body size seems to be lower in the Baltic. Accordingly, wefound a noticeable decrease in sexual size dimorphism in the Baltic population. Weconclude that, although far from negating the significance of other selective processes,sexual selection seems to have a decisive role in supporting pipefish sexualsize asymmetries.

    Ladda ner fulltext (pdf)
    fulltext
  • 26.
    Dahlgren, Elin
    et al.
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik. Swedish Environm Protect Agcy.
    Lehtilä, Kari
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, Miljövetenskap.
    Tolerance to apical and leaf damage of Raphanus raphanistrum in different competitive regimes2015Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 5, nr 22, s. 5193-5202Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tolerance to herbivory is an adaptation that promotes regrowth and maintains fitness in plants after herbivore damage. Here, we hypothesized that the effect of competition on tolerance can be different for different genotypes within a species and we tested how tolerance is affected by competitive regime and damage type. We inflicted apical or leaf damage in siblings of 29 families of an annual plant Raphanus raphanistrum (Brassicaceae) grown at high or low competition. There was a negative correlation of family tolerance levels between competition treatments: plant families with high tolerance to apical damage in the low competition treatment had low tolerance to apical damage in the high competition treatment and vice versa. We found no costs of tolerance, in terms of a trade-off between tolerance to apical and leaf damage or between tolerance and competitive ability, or an allocation cost in terms of reduced fitness of highly tolerant families in the undamaged state. High tolerance bound to a specific competitive regime may entail a cost in terms of low tolerance if competitive regime changes. This could act as a factor maintaining genetic variation for tolerance.

  • 27.
    Dalerum, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Oviedo, Spain; University of Pretoria, South Africa.
    Retief, Tarryn Anne
    Havemann, Carl Peter
    Chimimba, Christian T.
    van Rensburg, Berndt Janse
    The influence of distance to perennial surface water on ant communities in Mopane woodlands, northern Botswana2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 1, s. 154-165Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Studies of biodiversity along environmental gradients provide information on how ecological communities change in response to biotic and abiotic factors. For instance, distance to water is associated with several factors that shape the structure and the functioning of ecosystems at a range of spatial scales. We investigated the influence of distance to a perennial water source on ant communities in a semi-arid savanna in northern Botswana. Ant abundance, taxonomic richness, and both alpha and beta diversity were generally higher during the wet than the dry season. However, there were strong seasonal influences on the effects of distance to water, with more pronounced effects during the wet season. While both abundance and beta diversity declined with increasing distances to water during the wet season, there was a contrasting increase in alpha diversity. There was no major effect of distance to water on taxonomic richness during either season. Beta diversity was as high across as along gradients, and we found support for modular rather than nested community structures along gradients. Our study demonstrated that small-scale gradients in distance to water can influence several aspects of ant communities in semi-arid savannas. However, our results also point to strong effects of small-scale environmental variation, for instance associated with vegetation characteristics, soil properties, and plant community structure that are not directly linked to water access.

  • 28.
    de Boer, Raïssa A.
    et al.
    University of Antwerp, Belgium.
    Eens, Marcel
    Müller, Wendt
    A loss of heterozygosity, a loss in competition? The effects of inbreeding, pre- and postnatal conditions on nestling development.2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 21, s. 7921-7930Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The early developmental trajectory is affected by genetic and environmental factors that co-depend and interact often in a complex way. In order to distinguish their respective roles, we used canaries (Serinus canaria) of different genetic backgrounds (inbred and outbred birds). An artificial size hierarchy was created to provoke within-nest competition, manipulating postnatal conditions. To this end, inbred birds were weight-matched with outbred birds into duos, and each nest contained one duo of size-advantaged, and one duo of size-disadvantaged inbred and outbred nestlings. Prenatal (maternal) effects were taken into account also, enabling us to study the separate as well as the interactive effects of inbreeding, pre- and postnatal conditions on nestling development. We find that postnatal conditions were the most important determinant of early growth, with size-advantaged nestlings growing faster and obtaining larger size/body mass at fledging in comparison with size-disadvantaged nestlings. Prenatal conditions were important too, with birds that hatched from eggs that were laid late in the laying order obtaining a larger size at fledging than those hatched from early laid eggs. Inbreeding inhibited growth, but surprisingly this did not depend on (dis)advantageous pre- or postnatal conditions. Our findings imply that inbred individuals lose when they are in direct competition with same-sized outbred individuals regardless of the rearing conditions, and we thus propose that reduced competitiveness is one of the driving forces of inbreeding depression.

  • 29. de Heij, Maaike E.
    et al.
    Gustafsson, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Brommer, Jon E.
    Experimental manipulation shows that the white wing patch in collared flycatchers is a male sexual ornament2011Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 1, nr 4Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Descriptive analysis suggests that a conspicuous white wing patch in dichromatic (black and white) pied and collared flycatchers is under sexual selection. Here, we use an experimental approach to test whether this trait is indeed the target of selection. We caught 100 collared flycatcher Ficedula albicollis males soon after their arrival on the breeding site. We reduced (blackened) part of the white wing patch in half of these males and recorded their mating success and within and extra-pair offspring production. Reduction of the size of the white wing patch lowered a male's probability to attract a secondary social female, but not a primary female. However, primary females paired to males with a reduced wing patch were smaller (in tarsus), suggesting that male choice of partner or female-female competition over mates occurs in this species. The probability of pairing with a primary female (but not other components of male reproductive success) declined with arrival time (proxied by the date of capture). Males with a reduced wing patch size tended to sire less extra-pair offspring, although this relationship was reversed in one of the three study plots, suggesting that mating dynamics are context dependent. While our findings show that wing patch size is the target of sexual selection, the pathways and the strength of selection on this ornament differed markedly from a previous descriptive study. Nonexperimental studies of sexual selection in the wild may overestimate its importance because male fitness and ornamentation both depend positively on environmental conditions.

    Ladda ner fulltext (pdf)
    fulltext
  • 30. Delling, B.
    et al.
    Palm, S.
    Palkopoulou, E.
    Prestegaard, T.
    Genetic signs of multiple colonization events in Baltic ciscoes with radiation into sympatric spring- and autumn-spawners confined to early postglacial arrival2014Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 4Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Presence of sympatric populations may reflect local diversification or secondary contact of already distinct forms. The Baltic cisco (Coregonus albula) normally spawns in late autumn, but in a few lakes in Northern Europe sympatric autumn and spring- or winter-spawners have been described. So far, the evolutionary relationships and taxonomic status of these main life history forms have remained largely unclear. With microsatellites and mtDNA sequences, we analyzed extant and extinct spring- and autumn-spawners from a total of 23 Swedish localities, including sympatric populations. Published sequences from Baltic ciscoes in Germany and Finland, and Coregonus sardinella from North America were also included together with novel mtDNA sequences from Siberian C.sardinella. A clear genetic structure within Sweden was found that included two population assemblages markedly differentiated at microsatellites and apparently fixed for mtDNA haplotypes from two distinct clades. All sympatric Swedish populations belonged to the same assemblage, suggesting parallel evolution of spring-spawning rather than secondary contact. The pattern observed further suggests that postglacial immigration to Northern Europe occurred from at least two different refugia. Previous results showing that mtDNA in Baltic cisco is paraphyletic with respect to North American C.sardinella were confirmed. However, the inclusion of Siberian C.sardinella revealed a more complicated pattern, as these novel haplotypes were found within one of the two main C.albula clades and were clearly distinct from those in North American C.sardinella. The evolutionary history of Northern Hemisphere ciscoes thus seems to be more complex than previously recognized.

  • 31.
    Delling, Bo
    Naturhistoriska riksmuseet, Enheten för zoologi.
    Evolution and disappearance of sympatric Coregonus albula ina changing environment—A case study of the only remainingpopulation pair in Sweden2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 22, s. 12727-12753Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the past 50 years, Fennoscandian populations of spring‐spawning Baltic cisco

    (

    Coregonus albula), sympatric to common autumn‐spawners, have declined or disappeared;

    for example, three out of four known spring‐spawning populations in Sweden

    are regarded as extinct. Over the same period, the climate has changed and populations

    have been subject to other anthropogenic stressors. We compared historic

    (1960s) and recent (1990–000s) morphological data from the still‐existent sympatric

    cisco populations in Lake Fegen, Sweden. Phenotypic changes were found for

    spring‐spawners making them more similar to the sympatric autumn‐spawners that

    had remained virtually unchanged. Based on results for other salmoniform fishes,

    a phenotypically plastic response to increased temperature during early development

    appears unlikely. The recent material was also analyzed with microsatellite

    markers; long‐term effective population size in spring‐spawners was estimated to

    be about 20 times lower than autumn‐spawners, with signs of long‐term gene flow

    in both directions and a recent genetic bottleneck in spring‐spawners. We suggest

    the change toward a less distinct phenotype in spring‐spawners to reflect a recent

    increase in gene flow from autumn‐spawners. Time since divergence was estimated

    to only

    c. 1,900 years (95% CI: 400–5,900), but still the Fegen populations represent

    the most morphologically and genetically distinct sympatric populations studied.

    Consequently, we hypothesize that less distinct population pairs can be even

    younger and that spring‐spawning may have repeatedly evolved and disappeared in

    several lakes since the end of the last glaciation, concurrent with changed environmental

    conditions.

  • 32.
    Delling, Bo
    et al.
    Naturhistoriska riksmuseet, Enheten för zoologi.
    Palm, Stefan
    Palkopoulou, Eleftheria
    Prestegaard, Tore
    Genetic signs of multiple colonization events in Baltic ciscoes with radiation into sympatric spring- and autumnspawners confined to early postglacial arrival2014Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 4, nr 22, s. 4346-4360Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Presence of sympatric populations may reflect local diversification or secondary contact of already distinct forms. The Baltic cisco (Coregonus albula) normally spawns in late autumn, but in a few lakes in Northern Europe sympatric autumn and spring- or winter-spawners have been described. So far, the evolutionary relationships and taxonomic status of these main life history forms have remained largely unclear. With microsatellites and mtDNA sequences, we analyzed extant and extinct spring- and autumn-spawners from a total of 23 Swedish localities, including sympatric populations. Published sequences from Baltic ciscoes in Germany and Finland, and Coregonus sardinella from North America were also included together with novel mtDNA sequences from Siberian C. sardinella. A clear genetic structure within Sweden was found that included two population assemblages markedly differentiated at microsatellites and apparently fixed for mtDNA haplotypes from two distinct clades. All sympatric Swedish populations belonged to the same assemblage, suggesting parallel evolution of spring-spawning rather than secondary contact. The pattern observed further suggests that postglacial immigration to Northern Europe occurred from at least two different refugia. Previous results showing that mtDNA in Baltic cisco is paraphyletic with respect to North American C. sardinella were confirmed. However, the inclusion of Siberian C. sardinella revealed a more complicated pattern, as these novel haplotypes were found within one of the two main C. albula clades and were clearly distinct from those in North American C. sardinella. The evolutionary history of Northern Hemisphere ciscoes thus seems to be more complex than previously recognized.

    Ladda ner fulltext (pdf)
    fulltext
  • 33. Ecke, Frauke
    et al.
    Mahani, Seyed Alireza Nematollahi
    Evander, Magnus
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Avdelningen för virologi.
    Hörnfeldt, Birger
    Khalil, Hussein
    Wildfire-induced short-term changes in a small mammal community increase prevalence of a zoonotic pathogen?2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 22, s. 12459-12470Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Natural disturbances like droughts and fires are important determinants of wildlife community structure and are suggested to have important implications for prevalence of wildlife-borne pathogens. After a major wildfire affecting >1,600 ha of boreal forest in Sweden in 2006, we took the rare opportunity to study the short-term response (2007-2010 and 2015) of small mammal community structure, population dynamics, and prevalence of the Puumala orthohantavirus (PUUV) hosted by bank voles (Myodes glareolus). We performed snap-trapping in permanent trapping plots in clear-cuts (n = 3), unburnt reference forests (n = 7), and the fire area (n = 7) and surveyed vegetation and habitat structure. Small mammal species richness was low in all habitats (at maximum three species per trapping session), and the bank vole was the only small mammal species encountered in the fire area after the first postfire year. In autumns of years of peak rodent densities, the trapping index of bank voles was lowest in the fire area, and in two of three peak-density years, it was highest in clear-cuts. Age structure of bank voles varied among forest types with dominance of overwintered breeders in the fire area in the first postfire spring. PUUV infection probability in bank voles was positively related to vole age. Infection probability was highest in the fire area due to low habitat complexity in burnt forests, which possibly increased encounter rate among bank voles. Our results suggest that forest fires induce cascading effects, including fast recovery/recolonization of fire areas by generalists like bank voles, impoverished species richness of small mammals, and altered prevalence of a rodent-borne zoonotic pathogen. Our pilot study suggests high human infection risk upon encountering a bank vole in the fire area, however, with even higher overall risk in unburnt forests due to their higher vole numbers.

    Ladda ner fulltext (pdf)
    fulltext
  • 34.
    Erkosar, Berra
    et al.
    Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland.;Univ Lausanne, Dept Fundamental Microbiol, Lausanne, Switzerland..
    Yashiro, Erika
    Univ Lausanne, Dept Fundamental Microbiol, Lausanne, Switzerland..
    Zajitschek, Felix
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi. Univ New South Wales, Sch Biol Earth & Environm Sci, Evolut & Ecol Res Ctr, Sydney, NSW, Australia..
    Friberg, Urban
    Linkoping Univ, AVIAN Behav Genom & Physiol Grp, IFM Biol, Linkoping, Sweden..
    Maklakov, Alex A
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    van der Meer, Jan R.
    Univ Lausanne, Dept Fundamental Microbiol, Lausanne, Switzerland..
    Kawecki, Tadeusz J.
    Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland..
    Host diet mediates a negative relationship between abundance and diversity of Drosophila gut microbiota2018Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, nr 18, s. 9491-9502Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nutrient supply to ecosystems has major effects on ecological diversity, but it is unclear to what degree the shape of this relationship is general versus dependent on the specific environment or community. Although the diet composition in terms of the source or proportions of different nutrient types is known to affect gut microbiota composition, the relationship between the quantity of nutrients supplied and the abundance and diversity of the intestinal microbial community remains to be elucidated. Here, we address this relationship using replicate populations of Drosophila melanogaster maintained over multiple generations on three diets differing in the concentration of yeast (the only source of most nutrients). While a 6.5-fold increase in yeast concentration led to a 100-fold increase in the total abundance of gut microbes, it caused a major decrease in their alpha diversity (by 45-60% depending on the diversity measure). This was accompanied by only minor shifts in the taxonomic affiliation of the most common operational taxonomic units (OTUs). Thus, nutrient concentration in host diet mediates a strong negative relationship between the nutrient abundance and microbial diversity in the Drosophila gut ecosystem.

    Ladda ner fulltext (pdf)
    fulltext
  • 35.
    Erkosar, Berra
    et al.
    Univ Lausanne, Switzerland.
    Yashiro, Erika
    Univ Lausanne, Switzerland.
    Zajitschek, Felix
    Uppsala Univ, Sweden; Univ New South Wales, Australia.
    Friberg, Urban
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Maklakov, Alexei A.
    Uppsala Univ, Sweden.
    van der Meer, Jan R.
    Univ Lausanne, Switzerland.
    Kawecki, Tadeusz J.
    Univ Lausanne, Switzerland.
    Host diet mediates a negative relationship between abundance and diversity of Drosophila gut microbiota2018Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, nr 18, s. 9491-9502Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nutrient supply to ecosystems has major effects on ecological diversity, but it is unclear to what degree the shape of this relationship is general versus dependent on the specific environment or community. Although the diet composition in terms of the source or proportions of different nutrient types is known to affect gut microbiota composition, the relationship between the quantity of nutrients supplied and the abundance and diversity of the intestinal microbial community remains to be elucidated. Here, we address this relationship using replicate populations of Drosophila melanogaster maintained over multiple generations on three diets differing in the concentration of yeast (the only source of most nutrients). While a 6.5-fold increase in yeast concentration led to a 100-fold increase in the total abundance of gut microbes, it caused a major decrease in their alpha diversity (by 45-60% depending on the diversity measure). This was accompanied by only minor shifts in the taxonomic affiliation of the most common operational taxonomic units (OTUs). Thus, nutrient concentration in host diet mediates a strong negative relationship between the nutrient abundance and microbial diversity in the Drosophila gut ecosystem.

    Ladda ner fulltext (pdf)
    fulltext
  • 36.
    Ersmark, Erik
    et al.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Baryshnikov, Gennady
    Higham, Thomas
    Argant, Alain
    Castanos, Pedro
    Doeppes, Doris
    Gasparik, Mihaly
    Germonpre, Mietje
    Liden, Kerstin
    Lipecki, Grzegorz
    Marciszak, Adrian
    Miller, Rebecca
    Moreno-Garcia, Marta
    Pacher, Martina
    Robu, Marius
    Rodriguez-Varela, Ricardo
    Rojo Guerra, Manuel
    Sabol, Martin
    Spassov, Nikolai
    Stora, Jan
    Valdiosera, Christina
    Villaluenga, Aritza
    Stewart, John R.
    Dalen, Love
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Genetic turnovers and northern survival during the last glacial maximum in European brown bears2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 10, s. 5891-5905Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The current phylogeographic pattern of European brown bears (Ursus arctos) has commonly been explained by postglacial recolonization out of geographically distinct refugia in southern Europe, a pattern well in accordance with the expansion/contraction model. Studies of ancient DNA from brown bear remains have questioned this pattern, but have failed to explain the glacial distribution of mitochondrial brown bear clades and their subsequent expansion across the European continent. We here present 136 new mitochondrial sequences generated from 346 remains from Europe, ranging in age between the Late Pleistocene and historical times. The genetic data show a high Late Pleistocene diversity across the continent and challenge the strict confinement of bears to traditional southern refugia during the last glacial maximum (LGM). The mitochondrial data further suggest a genetic turnover just before this time, as well as a steep demographic decline starting in the mid-Holocene. Levels of stable nitrogen isotopes from the remains confirm a previously proposed shift toward increasing herbivory around the LGM in Europe. Overall, these results suggest that in addition to climate, anthropogenic impact and inter-specific competition may have had more important effects on the brown bear's ecology, demography, and genetic structure than previously thought.

    Ladda ner fulltext (pdf)
    fulltext
  • 37.
    Ersmark, Erik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of Natural History, Sweden.
    Baryshnikov, Gennady
    Higham, Thomas
    Argant, Alain
    Castaños, Pedro
    Döppes, Doris
    Gasparik, Mihaly
    Germonpré, Mietje
    Lidén, Kerstin
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur.
    Lipecki, Grzegorz
    Marciszak, Adrian
    Miller, Rebecca
    Moreno-García, Marta
    Pacher, Martina
    Robu, Marius
    Rodriguez-Varela, Ricardo
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur.
    Rojo Guerra, Manuel
    Sabol, Martin
    Spassov, Nikolai
    Storå, Jan
    Stockholms universitet, Humanistiska fakulteten, Institutionen för arkeologi och antikens kultur.
    Valdiosera, Christina
    Villaluenga, Aritza
    Stewart, John R.
    Dalén, Love
    Genetic turnovers and northern survival during the last glacial maximum in European brown bears2019Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 9, nr 10, s. 5891-5905Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The current phylogeographic pattern of European brown bears (Ursus arctos) has commonly been explained by postglacial recolonization out of geographically distinct refugia in southern Europe, a pattern well in accordance with the expansion/contraction model. Studies of ancient DNA from brown bear remains have questioned this pattern, but have failed to explain the glacial distribution of mitochondrial brown bear clades and their subsequent expansion across the European continent. We here present 136 new mitochondrial sequences generated from 346 remains from Europe, ranging in age between the Late Pleistocene and historical times. The genetic data show a high Late Pleistocene diversity across the continent and challenge the strict confinement of bears to traditional southern refugia during the last glacial maximum (LGM). The mitochondrial data further suggest a genetic turnover just before this time, as well as a steep demographic decline starting in the mid-Holocene. Levels of stable nitrogen isotopes from the remains confirm a previously proposed shift toward increasing herbivory around the LGM in Europe. Overall, these results suggest that in addition to climate, anthropogenic impact and inter-specific competition may have had more important effects on the brown bear's ecology, demography, and genetic structure than previously thought.

  • 38. Firbank, Les G.
    et al.
    Bertora, Chiara
    Blankman, David
    Delle Vedove, Gemini
    Frenzel, Mark
    Grignani, Carlo
    Groner, Elli
    Kertész, Miklós
    Krab, Eveline J.
    Department of Ecological Science, VU University Amsterdam, Amsterdam, The Netherlands.
    Matteucci, Giorgio
    Menta, Christina
    Mueller, Carsten W.
    Stadler, Jutta
    Kunin, William E.
    Towards the co-ordination of terrestrial ecosystem protocols across European research infrastructures2017Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 7, nr 11, s. 3967-3975Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The study of ecosystem processes over multiple scales of space and time is often best achieved using comparable data from multiple sites. Yet, long-term ecological observatories have often developed their own data collection protocols. Here, we address this problem by proposing a set of ecological protocols suitable for widespread adoption by the ecological community. Scientists from the European ecological research community prioritized terrestrial ecosystem parameters that could benefit from a more consistent approach to data collection within the resources available at most long-term ecological observatories. Parameters for which standard methods are in widespread use, or for which methods are evolving rapidly, were not selected. Protocols were developed by domain experts, building on existing methods where possible, and refined through a process of field testing and training. They address above-ground plant biomass; decomposition; land use and management; leaf area index; soil mesofaunal diversity; soil C and N stocks, and greenhouse gas emissions from soils. These complement existing methods to provide a complete assessment of ecological integrity. These protocols offer integrated approaches to ecological data collection that are low cost and are starting to be used across the European Long Term Ecological Research community.

  • 39. Flores, Olivier
    et al.
    Garnier, Eric
    Wright, Ian J.
    Reich, Peter B.
    Pierce, Simon
    Diaz, Sandra
    Pakeman, Robin J.
    Rusch, Graciela M.
    Bernard-Verdier, Maud
    Testi, Baptiste
    Bakker, Jan P.
    Bekker, Renee M.
    Cerabolini, Bruno E. L.
    Ceriani, Roberta M.
    Cornu, Guillaume
    Cruz, Pablo
    Delcamp, Matthieu
    Dolezal, Jiri
    Eriksson, Ove
    Stockholms universitet, Naturvetenskapliga fakulteten, Botaniska institutionen.
    Fayolle, Adeline
    Freitas, Helena
    Golodets, Carly
    Gourlet-Fleury, Sylvie
    Hodgson, John G.
    Brusa, Guido
    Kleyer, Michael
    Kunzmann, Dieter
    Lavorel, Sandra
    Papanastasis, Vasilios P.
    Perez-Harguindeguy, Natalia
    Vendramini, Fernanda
    Weiher, Evan
    An evolutionary perspective on leaf economics: phylogenetics of leaf mass per area in vascular plants2014Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 4, nr 14, s. 2799-2811Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In plant leaves, resource use follows a trade-off between rapid resource capture and conservative storage. This worldwide leaf economics spectrum consists of a suite of intercorrelated leaf traits, among which leaf mass per area, LMA, is one of the most fundamental as it indicates the cost of leaf construction and light-interception borne by plants. We conducted a broad-scale analysis of the evolutionary history of LMA across a large dataset of 5401 vascular plant species. The phylogenetic signal in LMA displayed low but significant conservatism, that is, leaf economics tended to be more similar among close relatives than expected by chance alone. Models of trait evolution indicated that LMA evolved under weak stabilizing selection. Moreover, results suggest that different optimal phenotypes evolved among large clades within which extremes tended to be selected against. Conservatism in LMA was strongly related to growth form, as were selection intensity and phenotypic evolutionary rates: woody plants showed higher conservatism in relation to stronger stabilizing selection and lower evolutionary rates compared to herbaceous taxa. The evolutionary history of LMA thus paints different evolutionary trajectories of vascular plant species across clades, revealing the coordination of leaf trait evolution with growth forms in response to varying selection regimes.

  • 40.
    Fors, Lisa
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Mozuraitis, Raimondas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. Nature Research Centre, Lithuania.
    Blažytė‐Čereškienė, Laima
    Verschut, Thomas A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Hambäck, Peter A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Selection by parasitoid females among closely related hosts based on volatiles: Identifying relevant chemical cues2018Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, nr 6, s. 3219-3228Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Parasitoid fitness is influenced by the ability to overcome host defense strategies and by the ability of parasitoid females to select high-quality host individuals. When females are unable to differentiate among hosts, their fitness will decrease with an increasing abundance of resistant hosts. To understand the effect of mixed host populations on female fitness, it is therefore necessary to investigate the ability of female parasitoids to select among hosts. Here, we used behavioral assays, headspace volatile collection, and electrophysiology to study the ability of Asecodes parviclava to use olfactory cues to select between a susceptible host (Galerucella calmariensis) and a resistant host (Galerucella pusilla) from a distance. Our studies show that parasitoid females have the capacity to distinguish the two hosts and that the selection behavior is acquired through experiences during earlier life stages. Further, we identified two volatiles (-terpinolene and [E]--ocimene) which amounts differ between the two plant-herbivore systems and that caused behavioral and electrophysiological responses. The consequence of this selection behavior is that females have the capacity to avoid laying eggs in G.pusilla, where the egg mortality is higher due to much stronger immune responses toward A.parviclava than in larvae of G.calmariensis.

  • 41.
    Forsman, Anders
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Berggren, Hanna
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Can spatial sorting associated with spawning migration explain evolution of body size and vertebral number in Anguilla eels?2017Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 7, nr 2, s. 751-761Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spatial sorting is a process that can contribute to microevolutionary change by assemblingphenotypes through space, owing to nonrandom dispersal. Here we first buildupon and develop the “neutral” version of the spatial sorting hypothesis by arguingthat in systems that are not characterized by repeated range expansions, the evolutionaryeffects of variation in dispersal capacity and assortative mating might not beindependent of but interact with natural selection. In addition to generating assortativemating, variation in dispersal capacity together with spatial and temporal variationin quality of spawning area is likely to influence both reproductive success and survivalof spawning migrating individuals, and this will contribute to the evolution of dispersal-enhancingtraits. Next, we use a comparative approach to examine whether differencesin spawning migration distance among 18 species of freshwater Anguilla eelshave evolved in tandem with two dispersal-favoringtraits. In our analyses, we use informationon spawning migration distance, body length, and vertebral number thatwas obtained from the literature, and a published whole mitochondrial DNA-basedphylogeny. Results from comparative analysis of independent contrasts showed thatmacroevolutionary shifts in body length throughout the phylogeny have been associatedwith concomitant shifts in spawning migration. Shifts in migration distance werenot associated with shifts in number of vertebrae. These findings are consistent withthe hypothesis that spatial sorting has contributed to the evolution of more elongatedbodies in species with longer spawning migration distances, or resulted in evolution oflonger migration distances in species with larger body size. This novel demonstrationis important in that it expands the list of ecological settings and hierarchical levels ofbiological organization for which the spatial sorting hypothesis seems to have predictivepower.

  • 42.
    Fuentes-Hurtado, Marcelo
    et al.
    Departamento de Ecosistemas y Medio Ambiente, Pontificia Universidad Católica de Chile, Santiago, Chile.
    Hof, Anouschka R.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences (SLU), Umeå, Sweden.
    Jansson, Roland
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Paleodistribution modeling suggests glacial refugia in Scandinavia and out-of-Tibet range expansion of the Arctic fox2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 1, s. 170-180Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quaternary glacial cycles have shaped the geographic distributions and evolution of numerous species in the Arctic. Ancient DNA suggests that the Arctic fox went extinct in Europe at the end of the Pleistocene and that Scandinavia was subsequently recolonized from Siberia, indicating inability to track its habitat through space as climate changed. Using ecological niche modeling, we found that climatically suitable conditions for Arctic fox were found in Scandinavia both during the last glacial maximum (LGM) and the mid-Holocene. Our results are supported by fossil occurrences from the last glacial. Furthermore, the model projection for the LGM, validated with fossil records, suggested an approximate distance of 2000 km between suitable Arctic conditions and the Tibetan Plateau well within the dispersal distance of the species, supporting the recently proposed hypothesis of range expansion from an origin on the Tibetan Plateau to the rest of Eurasia. The fact that the Arctic fox disappeared from Scandinavia despite suitable conditions suggests that extant populations may be more sensitive to climate change than previously thought.

    Ladda ner fulltext (pdf)
    fulltext
  • 43. Garlovsky, Martin D.
    et al.
    Snook, Rhonda R.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Sheffield, UK.
    Persistent postmating, prezygotic reproductive isolation between populations2018Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, nr 17, s. 9062-9073Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Studying reproductive barriers between populations of the same species is critical to understand how speciation may proceed. Growing evidence suggests postmating, prezygotic (PMPZ) reproductive barriers play an important role in the evolution of early taxonomic divergence. However, the contribution of PMPZ isolation to speciation is typically studied between species in which barriers that maintain isolation may not be those that contributed to reduced gene flow between populations. Moreover, in internally fertilizing animals, PMPZ isolation is related to male ejaculatefemale reproductive tract incompatibilities but few studies have examined how mating history of the sexes can affect the strength of PMPZ isolation and the extent to which PMPZ isolation is repeatable or restricted to particular interacting genotypes. We addressed these outstanding questions using multiple populations of Drosophila montana. We show a recurrent pattern of PMPZ isolation, with flies from one population exhibiting reproductive incompatibility in crosses with all three other populations, while those three populations were fully fertile with each other. Reproductive incompatibility is due to lack of fertilization and is asymmetrical, affecting female fitness more than males. There was no effect of male or female mating history on reproductive incompatibility, indicating that PMPZ isolation persists between populations. We found no evidence of variability in fertilization outcomes attributable to different femalexmale genotype interactions, and in combination with our other results, suggests that PMPZ isolation is not driven by idiosyncratic genotypexgenotype interactions. Our results show PMPZ isolation as a strong, consistent barrier to gene flow early during speciation and suggest several targets of selection known to affect ejaculate-female reproductive tract interactions within species that may cause this PMPZ isolation.

  • 44.
    George, Rushingisha
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. Tanzania Fisheries Research Institute (TAFIRI), Tanzania .
    Gullström, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Mangora, Mwita M.
    Mtolera, Matern S. P.
    Björk, Mats
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    High midday temperature stress has stronger effects on biomass than on photosynthesis: A mesocosm experiment on four tropical seagrass species2018Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, nr 9, s. 4508-4517Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effect of repeated midday temperature stress on the photosynthetic performance and biomass production of seagrass was studied in a mesocosm setup with four common tropical species, including Thalassia hemprichii, Cymodocea serrulata, Enhalus acoroides, and Thalassodendron ciliatum. To mimic natural conditions during low tides, the plants were exposed to temperature spikes of different maximal temperatures, that is, ambient (29-33 degrees C), 34, 36, 40, and 45 degrees C, during three midday hours for seven consecutive days. At temperatures of up to 36 degrees C, all species could maintain full photosynthetic rates (measured as the electron transport rate, ETR) throughout the experiment without displaying any obvious photosynthetic stress responses (measured as declining maximal quantum yield, Fv/Fm). All species except T.ciliatum could also withstand 40 degrees C, and only at 45 degrees C did all species display significantly lower photosynthetic rates and declining Fv/Fm. Biomass estimation, however, revealed a different pattern, where significant losses of both above- and belowground seagrass biomass occurred in all species at both 40 and 45 degrees C (except for C.serrulata in the 40 degrees C treatment). Biomass losses were clearly higher in the shoots than in the belowground root-rhizome complex. The findings indicate that, although tropical seagrasses presently can cope with high midday temperature stress, a few degrees increase in maximum daily temperature could cause significant losses in seagrass biomass and productivity.

  • 45.
    George, Rushingisha
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. Tanzania Fisheries Research Institute (TAFIRI), Tanzania.
    Gullström, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik. University of Gothenburg, Sweden.
    Mtolera, Matern S. P.
    Lyimo, Thomas J.
    Björk, Mats
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Methane emission and sulfide levels increase in tropical seagrass sediments during temperature stress: A mesocosm experiment2020Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 10, nr 4, s. 1917-1928Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Climate change-induced ocean warming is expected to greatly affect carbon dynamics and sequestration in vegetated shallow waters, especially in the upper subtidal where water temperatures may fluctuate considerably and can reach high levels at low tides. This might alter the greenhouse gas balance and significantly reduce the carbon sink potential of tropical seagrass meadows. In order to assess such consequences, we simulated temperature stress during low tide exposures by subjecting seagrass plants (Thalassia hemprichii) and associated sediments to elevated midday temperature spikes (31, 35, 37, 40, and 45 degrees C) for seven consecutive days in an outdoor mesocosm setup. During the experiment, methane release from the sediment surface was estimated using gas chromatography. Sulfide concentration in the sediment pore water was determined spectrophotometrically, and the plant's photosynthetic capacity as electron transport rate (ETR), and maximum quantum yield (Fv/Fm) was assessed using pulse amplitude modulated (PAM) fluorometry. The highest temperature treatments (40 and 45 degrees C) had a clear positive effect on methane emission and the level of sulfide in the sediment and, at the same time, clear negative effects on the photosynthetic performance of seagrass plants. The effects observed by temperature stress were immediate (within hours) and seen in all response variables, including ETR, Fv/Fm, methane emission, and sulfide levels. In addition, both the methane emission and the size of the sulfide pool were already negatively correlated with changes in the photosynthetic rate (ETR) during the first day, and with time, the correlations became stronger. These findings show that increased temperature will reduce primary productivity and increase methane and sulfide levels. Future increases in the frequency and severity of extreme temperature events could hence reduce the climate mitigation capacity of tropical seagrass meadows by reducing CO2 sequestration, increase damage from sulfide toxicity, and induce the release of larger amounts of methane.

  • 46.
    Goncalves, Ines Braga
    et al.
    Univ Zurich, Dept Evolutionary Biol & Environm Studies, Anim Behav, Winterthurerstr 190, CH-8057 Zurich, Switzerland.;Univ Gothenburg, Dept Biol & Environm Sci, POB 463, S-40530 Gothenburg, Sweden..
    Ahnesjö, Ingrid
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Kvarnemo, Charlotta
    Univ Gothenburg, Dept Biol & Environm Sci, POB 463, S-40530 Gothenburg, Sweden..
    Evolutionary ecology of pipefish brooding structures: embryo survival and growth do not improve with a pouch2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 11, s. 3608-3620Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For animals that reproduce in water, many adaptations in life-history traits such as egg size, parental care, and behaviors that relate to embryo oxygenation are still poorly understood. In pipefishes, seahorses and seadragons, males care for the embryos either in some sort of brood pouch, or attached ventrally to the skin on their belly or tail. Typically, egg size is larger in the brood pouch group and it has been suggested that oxygen supplied via the pouch buffers the developing embryos against hypoxia and as such is an adaptation that has facilitated the evolution of larger eggs. Here, using four pipefish species, we tested whether the presence or absence of brood pouch relates to how male behavior, embryo size, and survival are affected by hypoxia, with normoxia as control. Two of our studied species Entelurus aequoreus and Nerophis ophidion (both having small eggs) have simple ventral attachment of eggs onto the male trunk, and the other two, Syngnathus typhle (large eggs) and S. rostellatus (small eggs), have fully enclosed brood pouches on the tail. Under hypoxia, all species showed lower embryo survival, while species with brood pouches suffered greater embryo mortality compared to pouchless species, irrespective of oxygen treatment. Behaviorally, species without pouches spent more time closer to the surface, possibly to improve oxygenation. Overall, we found no significant benefits of brood pouches in terms of embryo survival and size under hypoxia. Instead, our results suggest negative effects of large egg size, despite the protection of brood pouches.

    Ladda ner fulltext (pdf)
    fulltext
  • 47.
    Goug, Leonie A.
    et al.
    Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, Aas NO-1432, Norway, Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot, Berkshire, SL5 7PY, United Kingdom.
    Sverdrup-Thygeson, Anne
    Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, Aas NO-1432, Norway.
    Milberg, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Pilskog, Hanne E.
    Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, Aas NO-1432, Norway.
    Jansson, Nicklas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jonsell, Mats
    Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, Uppsala SE-750 07, Sweden.
    Birkemoe, Tone
    Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, Aas NO-1432, Norway.
    Specialists in ancient trees are more affected by climate than generalists2015Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 5, nr 23, s. 5632-5641Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ancient trees are considered one of the most important habitats for biodiversityin Europe and North America. They support exceptional numbers of specializedspecies, including a range of rare and endangered wood-living insects. In thisstudy, we use a dataset of 105 sites spanning a climatic gradient along the oakrange of Norway and Sweden to investigate the importance of temperature andprecipitation on beetle species richness in ancient, hollow oak trees. We expectedthat increased summer temperature would positively influence all wood-livingbeetle species whereas precipitation would be less important with a negligible ornegative impact. Surprisingly, only oak-specialist beetles with a northern distributionincreased in species richness with temperature. Few specialist beetles and nogeneralist beetles responded to the rise of 4°C in summer as covered by our climaticgradient. The negative effect of precipitation affected more specialist speciesthan did temperature, whereas the generalists remained unaffected. In summary,we suggest that increased summer temperature is likely to benefit a few specialistbeetles within this dead wood community, but a larger number of specialists arelikely to decline due to increased precipitation. In addition, generalist species willremain unaffected. To minimize adverse impacts of climate change on this importantcommunity, long-term management plans for ancient trees are important.

    Ladda ner fulltext (pdf)
    fulltext
  • 48. Hakala, Sanja M.
    et al.
    Ittonen, Mats
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of Helsinki, Finland.
    Seppä, Perttu
    Helanterä, Heikki
    Limited dispersal and an unexpected aggression pattern in a native supercolonial ant2020Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 10, nr 8, s. 3671-3685Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding how social groups function requires studies on how individuals move across the landscape and interact with each other. Ant supercolonies are extreme cooperative units that may consist of thousands of interconnected nests, and their individuals cooperate over large spatial scales. However, the inner structure of suggested supercolonial (or unicolonial) societies has rarely been extensively studied using both genetic and behavioral analyses. We describe a dense supercolony‐like aggregation of more than 1,300 nests of the ant Formica (Coptoformica pressilabris . We performed aggression assays and found that, while aggression levels were generally low, there was some aggression within the assumed supercolony. The occurrence of aggression increased with distance from the focal nest, in accordance with the genetically viscous population structure we observe by using 10 DNA microsatellite markers. However, the aggressive interactions do not follow any clear pattern that would allow specifying colony borders within the area. The genetic data indicate limited gene flow within and away from the supercolony. Our results show that a Formica supercolony is not necessarily a single unit but can be a more fluid mosaic of aggressive and amicable interactions instead, highlighting the need to study internest interactions in detail when describing supercolonies.

  • 49. Hambäck, Peter A.
    et al.
    Weingartner, Elisabeth
    Dalén, Love
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Wirta, Helena
    Roslin, Tomas
    Spatial subsidies in spider diets vary with shoreline structure: Complementary evidence from molecular diet analysis and stable isotopes2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 23, s. 8431-8439Artikel i tidskrift (Refereegranskat)
    Ladda ner fulltext (pdf)
    fulltext
  • 50.
    Hambäck, Peter A.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Weingartner, Elisabeth
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Dalén, Love
    Wirta, Helena
    Roslin, Tomas
    Spatial subsidies in spider diets vary with shoreline structure: Complementary evidence from molecular diet analysis and stable isotopes2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 23, s. 8431-8439Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Inflow of matter and organisms may strongly affect the local density and diversity of organisms. This effect is particularly evident on shores where organisms with aquatic larval stages enter the terrestrial food web. The identities of such trophic links are not easily estimated as spiders, a dominant group of shoreline predator, have external digestion. We compared trophic links and the prey diversity of spiders on different shore types along the Baltic Sea: on open shores and on shores with a reed belt bordering the water. A priori, we hypothesized that the physical structure of the shoreline reduces the flow between ecosystem and the subsidies across the sea-land interface. To circumvent the lack of morphologically detectable remains of spider prey, we used a combination of stable isotope and molecular gut content analyses. The two tools used for diet analysis revealed complementary information on spider diets. The stable isotope analysis indicated that spiders on open shores had a marine signal of carbon isotopes, while spiders on reedy shores had a terrestrial signal. The molecular analysis revealed a diverse array of dipteran and lepidopteran prey, where spiders on open and reedy shores shared a similar diet with a comparable proportion of chironomids, the larvae of which live in the marine system. Comparing the methods suggests that differences in isotope composition of the two spider groups occurred because of differences in the chironomid diets: as larvae, chironomids of reedy shores likely fed on terrestrial detritus and acquired a terrestrial isotope signature, while chironomids of open shores utilized an algal diet and acquired a marine isotope signature. Our results illustrate how different methods of diet reconstruction may shed light on complementary aspects of nutrient transfer. Overall, they reveal that reed belts can reduce connectivity between habitats, but also function as a source of food for predators.

1234 1 - 50 av 177
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf