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  • 1.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Berger, David
    Stockholm University, Faculty of Science, Department of Zoology. Uppsala University, Sweden.
    Gotthard, Karl
    Stockholm University, Faculty of Science, Department of Zoology.
    The evolution of alternative developmental pathways: footprints of selection on life-history traits in a butterfly2012In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 25, no 7, p. 1377-1388Article in journal (Refereed)
    Abstract [en]

    Developmental pathways may evolve to optimize alternative phenotypes across environments. However, the maintenance of such adaptive plasticity under relaxed selection has received little study. We compare the expression of life-history traits across two developmental pathways in two populations of the butterfly Pararge aegeria where both populations express a diapause pathway but one never expresses direct development in nature. In the population with ongoing selection on both pathways, the difference between pathways in development time and growth rate was larger, whereas the difference in body size was smaller compared with the population experiencing relaxed selection on one pathway. This indicates that relaxed selection on the direct pathway has allowed life-history traits to drift towards values associated with lower fitness when following this pathway. Relaxed selection on direct development was also associated with a higher degree of genetic variation for protandry expressed as within-family sexual dimorphism in growth rate. Genetic correlations for larval growth rate across sexes and pathways were generally positive, with the notable exception of correlation estimates that involved directly developing males of the population that experienced relaxed selection on this pathway. We conclude that relaxed selection on one developmental pathway appears to have partly disrupted the developmental regulation of life-history trait expression. This in turn suggests that ongoing selection may be responsible for maintaining adaptive developmental regulation along alternative developmental pathways in these populations.

  • 2.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Gotthard, Karl
    Stockholm University, Faculty of Science, Department of Zoology.
    Diapause induction and relaxed selection on alternative developmental pathways in a butterfly2015In: Journal of Animal Ecology, ISSN 0021-8790, E-ISSN 1365-2656, Vol. 84, no 2, p. 464-472Article in journal (Refereed)
    Abstract [en]

    Seasonal phenotypic plasticity entails differential trait expression depending on the time of season. The facultative induction of winter diapause in temperate insects is a developmental switch mechanism often leading to differential expression in life-history traits. However, when there is a latitudinal shift from a bivoltine to univoltine life cycle, selection for pathway-specific expression is disrupted, which may allow drift towards less optimal trait values within the non-selected pathway. We use field- and experimental data from five Swedish populations of Pararge aegeria to investigate latitudinal variation in voltinism, local adaptation in the diapause switch and footprints of selection on pathway-specific regulation of life-history traits and sexual dimorphism in larval development. Field data clearly illustrated how natural populations gradually shift from bivoltinism to univoltinism as latitude increases. This was supported experimentally as the decrease in direct development at higher latitudes was accompanied by increasing critical daylengths, suggesting local adaptation in the diapause switch. The differential expression among developmental pathways in development time and growth rate was significantly less pronounced in univoltine populations. Univoltine populations showed no significant signs of protandry during larval development, suggesting that erosion of the direct development pathway under relaxed selection has led to the loss of its sex-specific modifications.

  • 3.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Gotthard, Karl
    Stockholm University, Faculty of Science, Department of Zoology.
    Latitudinal phenological adaptation: diapause induction and differentiation between alternative developmental pathways in a butterflyManuscript (preprint) (Other academic)
    Abstract [en]

    1. Seasonal phenotypic plasticity entails differential trait expression depending on the time of season. The facultative induction of winter diapause in temperate insects is a developmental switch mechanism often leading to differential expression in life history traits. However, when there is a latitudinal shift from a bivoltine to univoltine life cycle, selection for pathway-specific expression is disrupted, which may allow drift towards less optimal trait values within the non-selected pathway.

    2. We use field- and experimental data from five Swedish populations of Pararge aegeria to investigate latitudinal variation in voltinism, local adaptation in the diapause switch, and footprints of selection on pathway-specific regulation of life history traits and sexual dimorphism in larval development.

    3. Field data clearly illustrated how natural populations gradually shift from bivoltinism to univoltinism as latitude increases. This was supported experimentally as the decrease in direct development at higher latitudes was accompanied by increasing critical daylengths, suggesting local adaptation in the diapause switch.

    4. The differential expression among developmental pathways in development time and growth rate was significantly less pronounced in univoltine populations. Univoltine populations showed no significant signs of protandry during larval development, suggesting that erosion of the direct development pathway under relaxed selection has led to the loss of its sex-specific modifications.

  • 4.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Gotthard, Karl
    The development and expression of seasonal polyphenism in life-history traits in the butterfly Pararge aegeriaManuscript (preprint) (Other academic)
  • 5.
    Aalberg Haugen, Inger Marie
    Stockholm University, Faculty of Science, Department of Zoology.
    The diapause switch: Evolution of alternative developmental pathways in a butterfly2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Diapause decision is a classic example of a threshold switch mechanism with cascading effects on morphology, behaviour and life-history traits. This thesis addresses the downstream effects of the insect diapause switch, with the main focus on pathway-specific regulation of life-history traits, using the speckled wood butterfly (Pararge aegeria) as a study species. The ultimate pathway decision is made towards the end of larval development and allows the larvae to take into account up-to-date information from the environment about future conditions (Paper I, IV). However, already from an early point in development the larvae are sensitive to environmental cues and continuously adjust their growth trajectory in accordance to current information about the environmental conditions to be expected in future (Paper IV). An asymmetry in the ability to change from one developmental pathway to another at a late point in larval development suggests that the diapause and the direct pathway require different physiological preparations (Paper IV). Pathway-specific regulation of traits downstream of the diapause switch is maintained by ongoing selection. When the direct pathway is not regularly expressed, as with a shift from bivoltinism to univoltinism, relaxed selection on the unexpressed pathway leads to genetic drift and loss of protandry (Paper II, III). Natural populations display local adaptations in the diapause switch with an increase in critical daylengths as there is a gradual shift from bivoltinism to univoltinism (Paper III). This thesis highlights two aspects of the diapause decision, the determination of how and when this decision is made as well as the way the resulting pathways are moulded by selection in order to produce adaptive seasonal polyphenism in life-history traits.

  • 6. Abalde, Samuel
    et al.
    Tellgren-Roth, Christian
    Heintz, Julia
    Pettersson, Olga Vinnere
    Jondelius, Ulf
    Stockholm University, Faculty of Science, Department of Zoology, Systematic Zoology.
    The draft genome of the microscopic Nemertoderma westbladi sheds light on the evolution of Acoelomorpha genomes2023In: Frontiers in Genetics, E-ISSN 1664-8021, Vol. 14, article id 1244493Article in journal (Refereed)
    Abstract [en]

    Background: Xenacoelomorpha is a marine clade of microscopic worms that is an important model system for understanding the evolution of key bilaterian novelties, such as the excretory system. Nevertheless, Xenacoelomorpha genomics has been restricted to a few species that either can be cultured in the lab or are centimetres long. Thus far, no genomes are available for Nemertodermatida, one of the group's main clades and whose origin has been dated more than 400 million years ago.Methods: DNA was extracted from a single specimen and sequenced with HiFi following the PacBio Ultra-Low DNA Input protocol. After genome assembly, decontamination, and annotation, the genome quality was benchmarked using two acoel genomes and one Illumina genome as reference. The gene content of three cnidarians, three acoelomorphs, four deuterostomes, and eight protostomes was clustered in orthogroups to make inferences of gene content evolution. Finally, we focused on the genes related to the ultrafiltration excretory system to compare patterns of presence/absence and gene architecture among these clades.Results: We present the first nemertodermatid genome sequenced from a single specimen of Nemertoderma westbladi. Although genome contiguity remains challenging (N50: 60 kb), it is very complete (BUSCO: 80.2%, Metazoa; 88.6%, Eukaryota) and the quality of the annotation allows fine-detail analyses of genome evolution. Acoelomorph genomes seem to be relatively conserved in terms of the percentage of repeats, number of genes, number of exons per gene and intron size. In addition, a high fraction of genes present in both protostomes and deuterostomes are absent in Acoelomorpha. Interestingly, we show that all genes related to the excretory system are present in Xenacoelomorpha except Osr, a key element in the development of these organs and whose acquisition seems to be interconnected with the origin of the specialised excretory system.Conclusion: Overall, these analyses highlight the potential of the Ultra-Low Input DNA protocol and HiFi to generate high-quality genomes from single animals, even for relatively large genomes, making it a feasible option for sequencing challenging taxa, which will be an exciting resource for comparative genomics analyses.

  • 7. Abbas, Muhammad Ghazanfar
    et al.
    Haris, Abdullah
    Binyameen, Muhammad
    Nazir, Abdul
    Mozūratis, Raimondas
    Stockholm University, Faculty of Science, Department of Zoology. Nature Research Centre, Lithuania.
    Azeem, Muhammad
    Chemical Composition, Larvicidal and Repellent Activities of Wild Plant Essential Oils against Aedes aegypti2023In: Biology, E-ISSN 2079-7737, Vol. 12, no 1, article id 8Article in journal (Refereed)
    Abstract [en]

    Bio-degradable and eco-friendly essential oils (EOs) extracted from Mentha longifolia, Salsola imbricata, Erigeron bonariensis, E. canadensis, Ailanthus altissima, and Zanthoxylum armatum were investigated for their repellent and larvicidal potential against Aedes aegypti mosquitoes. The EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis, A. altissima, and Z. armatum exhibited 99.0%, 96.8%, 40.2%, 41.7%, 29.1%, and 13.2% repellency against mosquitoes at a tested dose of 33.3 μg/cm2, respectively. In time span bioassays, the EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis showed more than 40% repellency for 60 min at a tested dose of 330 μg/cm2. Larvicidal bioassays revealed that larvae of Ae. aegypti were the most susceptible to M. longifolia (LC50, 39.3 mg/L), E. bonariensis (LC50, 26.0 mg/L), E. canadensis (LC50, 35.7 mg/L), and Z. armatum (LC50, 35.9 mg/L) EOs upon 48 h exposure. The most abundant constituents in the EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis and A. altissima were piperitone oxide (45.5%), carvone (39.9%), matricaria ester (43.1%), (31.7%) and eugenol (24.4%), respectively. Our study demonstrates that EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis might be used to control Ae. aegypti mosquitoes without harming humans or the environment.

  • 8. Abbey-Lee, Robin N.
    et al.
    Uhrig, Emily J.
    Zidar, Josefina
    Favati, Anna
    Stockholm University, Faculty of Science, Department of Zoology.
    Almberg, Johan
    Dahlbom, Josefin
    Winberg, Svante
    Løvlie, Hanne
    The Influence of Rearing on Behavior, Brain Monoamines, and Gene Expression in Three-Spined Sticklebacks2018In: Brain, behavior, and evolution, ISSN 0006-8977, E-ISSN 1421-9743, Vol. 91, no 4, p. 201-213Article in journal (Refereed)
    Abstract [en]

    The causes of individual variation in behavior are often not well understood, and potential underlying mechanisms include both intrinsic and extrinsic factors, such as early environmental, physiological, and genetic differences. In an exploratory laboratory study, we raised three-spined sticklebacks (Gasterosteus aculeatus) under 4 different environmental conditions (simulated predator environment, complex environment, variable social environment, and control). We investigated how these manipulations related to behavior, brain physiology, and gene expression later in life, with focus on brain dopamine and serotonin levels, turnover rates, and gene expression. The different rearing environments influenced behavior and gene expression, but did not alter monoamine levels or metabolites. Specifically, compared to control fish, fish exposed to a simulated predator environment tended to be less aggressive, more exploratory, and more neophobic; and fish raised in both complex and variable social environments tended to be less neophobic. Exposure to a simulated predator environment tended to lower expression of dopamine receptor DRD4A, a complex environment increased expression of dopamine receptor DRD1B, while a variable social environment tended to increase serotonin receptor 5-HTR2B and serotonin transporter SLC6A4A expression. Despite both behavior and gene expression varying with early environment, there was no evidence that gene expression mediated the relationship between early environment and behavior. Our results confirm that environmental conditions early in life can affect phenotypic variation. However, the mechanistic pathway of the monoaminergic systems translating early environmental variation into observed behavioral responses was not detected.

  • 9.
    Acerbi, Alberto
    et al.
    Department of Psychology, University of Bologna.
    Enquist, Magnus
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology, Department of Ethology.
    Ghirlanda, Stefano
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution.
    Cultural evolution and individual development of openness and conservatism2009In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 106, no 45, p. 18931-18935Article in journal (Refereed)
    Abstract [en]

    We present a model of cultural evolution in which an individual's propensity to engage in social learning is affected by social learning itself. We assume that individuals observe cultural traits displayed by others and decide whether to copy them based on their overall preference for the displayed traits. Preferences, too, can be transmitted between individuals. Our results show that such cultural dynamics tends to produce conservative individuals, i.e., individuals who are reluctant to copy new traits. Openness to new information, however, can be maintained when individuals need significant time to acquire the cultural traits that make them effective cultural models. We show that a gradual enculturation of young individuals by many models and a larger cultural repertoire to be acquired are favorable circumstances for the long-term maintenance of openness in individuals and groups. Our results agree with data about lifetime personality change, showing that openness to new information decreases with age. Our results show that cultural remodeling of cultural transmission is a powerful force in cultural evolution, i.e., that cultural evolution can change its own dynamics

  • 10.
    Acerbi, Alberto
    et al.
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution.
    Ghirlanda, Stefano
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution. Brooklyn College, USA.
    Enquist, Magnus
    Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology.
    Regulatory traits: Cultural influences on cultural evolution2014In: Evolution, Complexity and Artificial Life / [ed] Stefano Cagnoni, Marco Mirolli, Marco Villani, Springer Berlin/Heidelberg, 2014, p. 135-147Chapter in book (Refereed)
    Abstract [en]

    We use the term regulatory traits to indicate traits that both regulate cultural transmission (e.g., from whom to learn) and are themselves culturally transmitted. In the first part of this contribution we study the dynamics of some of these traits through simple mathematical models. In particular, we consider the cultural evolution of traits that determine the propensity to copy others, the ability to influence others, the number of individuals from whom one may copy, and the number of individuals one tries to influence. We then show how to extend these simple models to address more complex human cultural phenomena, such as ingroup biases, the emergence of open or conservative societies, and of cyclical, fashion-like, increases and decreases of popularity of cultural traits. We finally discuss how the ubiquity of regulatory traits in cultural evolution impacts on the analogy between genetic and cultural evolution and therefore on the possibility of using models inspired by evolutionary biology to study human cultural dynamics.

  • 11.
    Acerbi, Alberto
    et al.
    Stockholm University, Faculty of Humanities, Centre for Cultural Evolution.
    Ghirlanda, Stefano
    Stockholm University, Faculty of Humanities, Centre for Cultural Evolution. Brooklyn College, US.
    Enquist, Magnus
    Stockholm University, Faculty of Humanities, Centre for Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology, Ethology.
    Regulatory Traits in Cultural Evolution2012In: Proceedings of WiVACE 2012, 2012, p. 1-9Conference paper (Refereed)
    Abstract [en]

    We call "regulatory traits" those cultural traits that are transmitted through cultural interactions and, at the same time, change individual behaviors directly influencing the outcome of future cultural interactions. The cultural dynamics of some of those traits are studied through simple simulations. In particular, we consider the cultural evolution of traits determining the propensity to copy, the number of potential demonstrators from whom one individual may copy, and conformist versus anti conformist attitudes. Our results show that regulatory traits generate peculiar dynamics that may explain complex human cultural phenomena. We discuss how the existence and importance of regulatory traits in cultural evolution impact on the analogy between genetic and cultural evolution and therefore on the possibility of using evolutionary biology inspired models to study human cultural dynamics.

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  • 12.
    Acerbi, Alberto
    et al.
    Stockholm University, Faculty of Humanities, Centre for Cultural Evolution.
    Ghirlanda, Stefano
    Stockholm University, Faculty of Humanities, Centre for Cultural Evolution.
    Enquist, Magnus
    Stockholm University, Faculty of Humanities, Centre for Cultural Evolution. Stockholm University, Faculty of Science, Department of Zoology.
    The logic of fashion cycles2012In: PLOS ONE, E-ISSN 1932-6203, Vol. 7, no 3, p. e32541-Article in journal (Refereed)
    Abstract [en]

    Many cultural traits exhibit volatile dynamics, commonly dubbed fashions or fads. Here we show that realistic fashion-like dynamics emerge spontaneously if individuals can copy others' preferences for cultural traits as well as traits themselves. We demonstrate this dynamics in simple mathematical models of the diffusion, and subsequent abandonment, of a single cultural trait which individuals may or may not prefer. We then simulate the coevolution between many cultural traits and the associated preferences, reproducing power-law frequency distributions of cultural traits (most traits are adopted by few individuals for a short time, and very few by many for a long time), as well as correlations between the rate of increase and the rate of decrease of traits (traits that increase rapidly in popularity are also abandoned quickly and vice versa). We also establish that alternative theories, that fashions result from individuals signaling their social status, or from individuals randomly copying each other, do not satisfactorily reproduce these empirical observations.

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  • 13.
    Ackefors, H.
    Stockholm University, Faculty of Science, Department of Zoology. Zoologisk ekologi.
    Dramatisk ökning av odlade räkor, oro över räkfisket miljökonsekvenser.2007In: Vår Föda, Vol. 3, p. 32-35Article in journal (Other (popular science, discussion, etc.))
  • 14.
    Ackefors, Hans
    Stockholm University, Faculty of Science, Department of Zoology.
    Dramatisk ökning av odlade räkor - Oro över räkfiskets miljökonsekvenser2007In: Vår Föda, Vol. 3, p. 32-35Article in journal (Other (popular science, discussion, etc.))
  • 15.
    Ackefors, Hans
    Stockholm University, Faculty of Science, Department of Zoology, Animal Ecology.
    Global fisheries - threats and opportunities2009In: Fisheries, sustainablity and development: fifty-two authors on coexistence and development of fisheries and aquaculture in developing and developed countries / [ed] Per Wramner, Hans Ackefors et al, Stockholm: Kungl. Skogs- och lantbruksakademien , 2009, p. 35-68-Chapter in book (Other academic)
  • 16.
    Ackefors, Hans
    Stockholm University, Faculty of Science, Department of Zoology.
    Sveriges havs- och kustfiske.2007In: Människan och faunan, 2007: Etnobiologi i Sverige 3, 2007, p. 424-430Chapter in book (Other (popular science, discussion, etc.))
  • 17.
    Ackefors, Hans
    Stockholm University, Faculty of Science, Department of Zoology, Animal Ecology.
    The evolution of a worldwide shrimp industry2009In: World Aquaculture, ISSN 1041-5602, Vol. 40, no 3, p. 46-55Article in journal (Refereed)
  • 18.
    Ackefors, Hans
    Stockholm University, Faculty of Science, Department of Zoology, Animal Ecology.
    Är det politikerna eller fiskenäringen som styr fisket?2008In: Kungl. Skogs- och Lantbruksakademiens Tidskrift, ISSN 0023-5350, Vol. 147, no 2, p. 36-43Article in journal (Other (popular science, discussion, etc.))
  • 19.
    Agosta, Salvatore J
    et al.
    University of Toronto.
    Janz, Niklas
    Stockholm University, Faculty of Science, Department of Zoology.
    Brooks, Daniel R
    University of Toronto.
    How specialists can be generalists: resolving the "parasite paradox" and implications for emerging infectious disease2010In: Zoologia (Curitiba), ISSN 1984-4670, E-ISSN 1984-4689, Vol. 27, no 2, p. 151-162Article in journal (Refereed)
    Abstract [en]

    The parasite paradox arises from the dual observations that parasites (broadly construed, including phytophagous insects) are resource specialists with restricted host ranges, and yet shifts onto relatively unrelated hosts are common in the phylogenetic diversification of parasite lineages and directly observable in ecological time. We synthesize the emerging solution to this paradox: phenotypic flexibility and phylogenetic conservatism in traits related to resource use, grouped under the term ecological fitting, provide substantial opportunities for rapid host switching in changing environments, in the absence of the evolution of novel host-utilization capabilities. We discuss mechanisms behind ecological fitting, its implications for defining specialists and generalists, and briefly review empirical examples of host shifts in the context of ecological fitting. We conclude that host shifts via ecological fitting provide the fuel for the expansion phase of the recently proposed oscillation hypothesis of host range and speciation, and, more generally, the generation of novel combinations of interacting species within the geographic mosaic theory of coevolution. Finally, we conclude that taxon pulses, driven by climate change and large-scale ecological perturbation are drivers of biotic mixing and resultant ecological fitting, which leads to increased rates of rapid host switching, including the agents of Emerging Infectious Disease.

  • 20. Aguirre, A. A.
    et al.
    Angerbjörn, A.
    Stockholm University, Faculty of Science, Department of Zoology, Animal Ecology.
    Tannerfeldt, Magnus
    Stockholm University, Faculty of Science, Department of Zoology.
    Mörner, T.
    Health evaluation of arctic fox (Alopex lagopus) cubs in Sweden2000In: Journal of zoo and wildlife medicine, ISSN 1042-7260, E-ISSN 1937-2825, Vol. 31, no 1, p. 36-40Article in journal (Refereed)
    Abstract [en]

    Hematologic. serum biochemistry, and serum cortisol reference ranges were established and tonsil/rectal bacterial and fecal parasite examinations were performed on 21 wild arctic fox (Alopex lagopus) cubs during July 1996. Several of the hematologic and serum biochemistry values fell within normal ranges for other wild canids or domestic dogs of the same age class. Serum alanine transaminase and creatine phosphokinase values were significantly higher in the youngest cubs. Proteus vulgaris and Escherichia coli were isolated from both tonsilar and rectal swabs of several cubs in all dens. The most common gastrointestinal parasite ova were Toxascaris leonina (59%), Isospora spp. (52%), Uncinaria stenocephala (33%), and Capillaria spp. (26%). Prevalence of T. leonina differed significantly between dens and between age groups. Hematologic and serum biochemistry values and degree of parasitism may be indicators of health, stress, and nutritional status of arctic foxes.

  • 21. Aguirre, A. Alonso
    et al.
    Principe, B.
    Tannerfeldt, Magnus
    Stockholm University, Faculty of Science, Department of Zoology.
    Angerbjörn, Anders
    Stockholm University, Faculty of Science, Department of Zoology.
    Mörner, Torsten
    Field anesthesia of wild arctic fox (Alopex lagopus) cubs in the Swedish lapland using medetomidine-ketamine-atipamezole2000In: Journal of zoo and wildlife medicine, ISSN 1042-7260, E-ISSN 1937-2825, Vol. 31, no 2, p. 244-246Article in journal (Refereed)
    Abstract [en]

    A safe and effective anesthetic regime for use in arctic fox (Alopex lagopus) cubs was developed. During July 1996, six free-ranging 6-8-wk-old cubs were captured near their den in Vindelfjallen Nature Reserve, Sweden. Medetomidine and ketamine HCl, followed by atipamezole, were selected for the anesthetic trial because of the well-documented safety and efficacy of this drug combination in a broad range of species. The dosage regimen used was 50 mu g/kg medetomidine combined with 2.5 mg/kg ketamine followed by reversal with 250 mu g/kg atipamezole. induction was rapid, with a mean induction time of 1 min and 32 sec (range: 58-150 sec). The cubs were anesthetized for a mean time of 18 +/- 5 min (range: 13-25 min). Serially recorded heart rate, respiratory rate, temperature, and pulse oximetry were stable throughout the anesthetic period for all cubs. Anesthetic depth was suitable for safe handling and minor clinical procedures, including venipuncture. Following atipamezole, all cubs were standing within 12 +/- 7 min (range: 5-24 min) and fully recovered at 27 +/- 5 min (range: 19-36 min). This information will be useful for future captive breeding and management programs involving the endangered arctic fox.

  • 22. Ah-King, M
    et al.
    Elofsson, Helena
    Stockholm University, Faculty of Science, Department of Zoology.
    Kvarnemo, C
    Rosenquist, G
    Berglund, A
    Why no sperm competition in pipefish with externally brooding males?Manuscript (Other academic)
  • 23. Ah-King, Malin
    et al.
    Nylin, Sören
    Stockholm University, Faculty of Science, Department of Zoology.
    Sex in an Evolutionary Perspective: Just Another Reaction Norm2010In: Evolutionary biology, ISSN 0071-3260, E-ISSN 1934-2845, Vol. 37, no 4, p. 234-246Article, review/survey (Refereed)
    Abstract [en]

    It is common to refer to all sorts of clear-cut differences between the sexes as something that is biologically almost inevitable. Although this does not reflect the status of evolutionary theory on sex determination and sexual dimorphism, it is probably a common view among evolutionary biologists as well, because of the impact of sexual selection theory. To get away from thinking about biological sex and traits associated with a particular sex as something static, it should be recognized that in an evolutionary perspective sex can be viewed as a reaction norm, with sex attributes being phenotypically plastic. Sex determination itself is fundamentally plastic, even when it is termed "genetic". The phenotypic expression of traits that are statistically associated with a particular sex always has a plastic component. This plasticity allows for much more variation in the expression of traits according to sex and more overlap between the sexes than is typically acknowledged. Here we review the variation and frequency of evolutionary changes in sex, sex determination and sex roles and conclude that sex in an evolutionary time-frame is extremely variable. We draw on recent findings in sex determination mechanisms, empirical findings of morphology and behaviour as well as genetic and developmental models to explore the concept of sex as a reaction norm. From this point of view, sexual differences are not expected to generally fall into neat, discrete, pre-determined classes. It is important to acknowledge this variability in order to increase objectivity in evolutionary research.

  • 24.
    Ahlgren, Hans
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Archaeological Research Laboratory.
    Bro-Jørgensen, Maiken Hemme
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Archaeological Research Laboratory. University of Copenhagen, Denmark.
    Glykou, Aikaterini
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Archaeological Research Laboratory.
    Schmölcke, Ulrich
    Angerbjorn, Anders
    Stockholm University, Faculty of Science, Department of Zoology.
    Olsen, Morten Tange
    Lidén, Kerstin
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies, Archaeological Research Laboratory.
    The Baltic grey seal: A 9000-year history of presence and absence2022In: The Holocene, ISSN 0959-6836, E-ISSN 1477-0911, Vol. 32, no 6, p. 569-577Article in journal (Refereed)
    Abstract [en]

    The grey seal (Halichoerus grypus) has been part of the Baltic Sea fauna for more than 9000 years and has ever since been subjected to extensive human hunting, particularly during the early phases of its presence in the Baltic Sea, but also in the early 20th century. In order to study their temporal genetic structure and to investigate whether there has been a genetically continuous grey seal population in the Baltic, we generated mitochondrial control region data from skeletal remains from ancient grey seals from the archaeological sites Stora Förvar (Sweden) and Neustadt (Germany) and compared these with modern grey seal data. We found that the majority of the Mesolithic grey seals represent haplotypes that is not found in contemporary grey seals, indicating that the Baltic Sea population went extinct, likely due to human overexploitation and environmental change. We hypothesize that grey seals recolonised the Baltic Sea from the North Sea. during the Bronze Age or Iron Age, and that the contemporary Baltic grey seal population is direct descendants of this recolonisation. Our study highlights the power of biomolecular archaeology to understand the factors that shape contemporary marine diversity. 

  • 25.
    Ahlgren, Hans
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Bro-Jørgensen, Maiken Hemme
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Larsson, Thomas B.
    Storå, Jan
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Angerbjörn, Anders
    Stockholm University, Faculty of Science, Department of Zoology.
    Lidén, Kerstin
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    The decline of a Stone Age moose population in northern SwedenManuscript (preprint) (Other academic)
  • 26.
    Ahlgren, Hans
    et al.
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Norén, Karin
    Stockholm University, Faculty of Science, Department of Zoology.
    Angerbjörn, Anders
    Stockholm University, Faculty of Science, Department of Zoology.
    Lidén, Kerstin
    Stockholm University, Faculty of Humanities, Department of Archaeology and Classical Studies.
    Multiple prehistoric introductions of the mountain hare (Lepus timidus) on a remote island, as revealed by ancient DNA2016In: Journal of Biogeography, ISSN 0305-0270, E-ISSN 1365-2699, Vol. 43, no 9, p. 1786-1796Article in journal (Refereed)
    Abstract [en]

    Aim: The majority of the non-volant mammals now present on the island of Gotland, Sweden, have been introduced in modern times. One exception is the mountain hare (Lepus timidus), which was present on the island more than 9000 years ago. This paper investigates the origins of the Gotland hares and temporal changes in their genetic structure, and considers how they may have reached the island.

    Location: The island of Gotland, Sweden (57°30′ N, 18°20′ E).

    Methods: Two fragments of the mitochondrial D-loop 130 + 164 base pairs in length from skeletal remains from 40 ancient mountain hares from Gotland, 38 from the Swedish mainland and five from Lithuania were analysed and compared with 90 modern L. timidus haplotypes from different locations in Eurasia and five haplotypes of the Don-hare (Lepus tanaiticus) morphotype.

    Results: The Mesolithic hares from Gotland (7304 bc–5989 bc) cluster with modern hares from Russia, Scotland, the Alps and Fennoscandia whereas the Gotland hares from the Neolithic and onwards (2848 bc–1641 ad) cluster with Neolithic hares from the Swedish mainland and modern hares from Fennoscandia. The Neolithic haplotypes from Lithuania and the Don-hare haplotypes were dispersed within the network. The level of differentiation (FST) between the Mesolithic and Neolithic hares on Gotland was twice as great as that observed on the mainland.

    Main conclusions: The ancient hares on Gotland fall into two haplogroups separated in time, indicating that the mountain hare became extinct at one point, with subsequent re-colonization events. In view of the isolated location of Gotland, it is probable that the hares were brought there by human means of transport.

  • 27.
    Ahmed, Mohammed
    et al.
    Stockholm University, Faculty of Science, Department of Zoology. Swedish Museum of Natural History, Sweden.
    Adedidran, Funmilola
    Stockholm University, Faculty of Science, Department of Zoology.
    Holovachov, Oleksandr
    Stockholm University, Faculty of Science, Department of Zoology. Swedish Museum of Natural History, Sweden.
    A draft transcriptome of a parasite Neocamacolaimus parasiticus (Camacolaimidae, Plectida)2021In: Journal of nematology, ISSN 0022-300X, Vol. 53, article id e2021-40Article in journal (Refereed)
    Abstract [en]

    Camacolaimidae is a clade of nematodes that include both freeliving epistrate feeding forms and parasites of marine protozoans and invertebrates. Neocamacolaimus parasiticus is a parasite of marine polychaete worms. Given its phylogenetic affinities to free-living species, Neocamacolaimus can be a reference for research of the origin of parasitism in an aquatic environment. Here, we present a draft transcriptome obtained from a single post-parasitic juvenile individual of this species. The final assembly consists of 19,180 protein coding sequences (including isoforms) with the following BUSCO scores for Nematoda: 65.38% complete, 9.06% partial, and 25.56% missing, and for Metazoa: 79.45% complete, 3.17% partial, and 17.38% missing.

  • 28. Ahmed, Mohammed
    et al.
    Roberts, Nickellaus G.
    Adediran, Funmilola
    Stockholm University, Faculty of Science, Department of Zoology.
    Smythe, Ashleigh B.
    Kocot, Kevin M.
    Holovachov, Oleksandr
    Phylogenomic Analysis of the Phylum Nematoda: Conflicts and Congruences With Morphology, 18S rRNA, and Mitogenomes2022In: Frontiers in Ecology and Evolution, E-ISSN 2296-701X, Vol. 9, article id 769565Article in journal (Refereed)
    Abstract [en]

    Phylogenetic relationships within many lineages of the phylum Nematoda remain unresolved, despite numerous morphology-based and molecular analyses. We performed several phylogenomic analyses using 286 published genomes and transcriptomes and 19 new transcriptomes by focusing on Trichinellida, Spirurina, Rhabditina, and Tylenchina separately, and by analyzing a selection of species from the whole phylum Nematoda. The phylogeny of Trichinellida supported the division of Trichinella into encapsulated and non-encapsulated species and placed them as sister to Trichuris. The Spirurina subtree supported the clades formed by species from Ascaridomorpha and Spiruromorpha respectively, but did not support Dracunculoidea. The analysis of Tylenchina supported a clade that included all sampled species from Tylenchomorpha and placed it as sister to clades that included sampled species from Cephalobomorpha and Panagrolaimomorpha, supporting the hypothesis that postulates the single origin of the stomatostylet. The Rhabditina subtree placed a clade composed of all sampled species from Diplogastridae as sister to a lineage consisting of paraphyletic Rhabditidae, a single representative of Heterorhabditidae and a clade composed of sampled species belonging to Strongylida. It also strongly supported all suborders within Strongylida. In the phylum-wide analysis, a clade composed of all sampled species belonging to Enoplia were consistently placed as sister to Dorylaimia + Chromadoria. The topology of the Nematoda backbone was consistent with previous studies, including polyphyletic placement of sampled representatives of Monhysterida and Araeolaimida.

  • 29. Ahola, Virpi
    et al.
    Lehtonen, Rainer
    Somervuo, Panu
    Salmela, Leena
    Koskinen, Patrik
    Rastas, Pasi
    Valimaki, Niko
    Paulin, Lars
    Kvist, Jouni
    Wahlberg, Niklas
    Tanskanen, Jaakko
    Hornett, Emily A.
    Ferguson, Laura C.
    Luo, Shiqi
    Cao, Zijuan
    de Jong, Maaike A.
    Duplouy, Anne
    Smolander, Olli-Pekka
    Vogel, Heiko
    McCoy, Rajiv C.
    Qian, Kui
    Chong, Wong Swee
    Zhang, Qin
    Ahmad, Freed
    Haukka, Jani K.
    Joshi, Aruj
    Salojarvi, Jarkko
    Wheat, Christopher W.
    Stockholm University, Faculty of Science, Department of Zoology.
    Grosse-Wilde, Ewald
    Hughes, Daniel
    Katainen, Riku
    Pitkanen, Esa
    Ylinen, Johannes
    Waterhouse, Robert M.
    Turunen, Mikko
    Vaharautio, Anna
    Ojanen, Sami P.
    Schulman, Alan H.
    Taipale, Minna
    Lawson, Daniel
    Ukkonen, Esko
    Makinen, Veli
    Goldsmith, Marian R.
    Holm, Liisa
    Auvinen, Petri
    Frilander, Mikko J.
    Hanski, Ilkka
    The Glanville fritillary genome retains an ancient karyotype and reveals selective chromosomal fusions in Lepidoptera2014In: Nature Communications, E-ISSN 2041-1723, Vol. 5, p. 4737-Article in journal (Refereed)
    Abstract [en]

    Previous studies have reported that chromosome synteny in Lepidoptera has been well conserved, yet the number of haploid chromosomes varies widely from 5 to 223. Here we report the genome (393 Mb) of the Glanville fritillary butterfly (Melitaea cinxia; Nymphalidae), a widely recognized model species in metapopulation biology and eco-evolutionary research, which has the putative ancestral karyotype of n = 31. Using a phylogenetic analyses of Nymphalidae and of other Lepidoptera, combined with orthologue-level comparisons of chromosomes, we conclude that the ancestral lepidopteran karyotype has been n = 31 for at least 140 My. We show that fusion chromosomes have retained the ancestral chromosome segments and very few rearrangements have occurred across the fusion sites. The same, shortest ancestral chromosomes have independently participated in fusion events in species with smaller karyotypes. The short chromosomes have higher rearrangement rate than long ones. These characteristics highlight distinctive features of the evolutionary dynamics of butterflies and moths.

  • 30. Akanyeti, Otar
    et al.
    Di Santo, Valentina
    Stockholm University, Faculty of Science, Department of Zoology, Functional Morphology.
    Goerig, Elsa
    Wainwright, Dylan K.
    Liao, James C.
    Castro-Santos, Theodore
    Lauder, George
    Fish-inspired segment models for undulatory steady swimming2022In: Bioinspiration & Biomimetics, ISSN 1748-3182, E-ISSN 1748-3190, Vol. 17, no 4, article id 046007Article in journal (Refereed)
    Abstract [en]

    Many aquatic animals swim by undulatory body movements and understanding the diversity of these movements could unlock the potential for designing better underwater robots. Here, we analyzed the steady swimming kinematics of a diverse group of fish species to investigate whether their undulatory movements can be represented using a series of interconnected multi-segment models, and if so, to identify the key factors driving the segment configuration of the models. Our results show that the steady swimming kinematics of fishes can be described successfully using parsimonious models, 83% of which had fewer than five segments. In these models, the anterior segments were significantly longer than the posterior segments, and there was a direct link between segment configuration and swimming kinematics, body shape, and Reynolds number. The models representing eel-like fishes with elongated bodies and fishes swimming at high Reynolds numbers had more segments and less segment length variability along the body than the models representing other fishes. These fishes recruited their anterior bodies to a greater extent, initiating the undulatory wave more anteriorly. Two shape parameters, related to axial and overall body thickness, predicted segment configuration with moderate to high success rate. We found that head morphology was a good predictor of its segment length. While there was a large variation in head segments, the length of tail segments was similar across all models. Given that fishes exhibited variable caudal fin shapes, the consistency of tail segments could be a result of an evolutionary constraint tuned for high propulsive efficiency. The bio-inspired multi-segment models presented in this study highlight the key bending points along the body and can be used to decide on the placement of actuators in fish-inspired robots, to model hydrodynamic forces in theoretical and computational studies, or for predicting muscle activation patterns during swimming.

  • 31. Aleknavičius, D.
    et al.
    Markaitytė, E.
    Būdienė, J.
    Blažytė-Čereškienė, L.
    Stanevičienė, R.
    Mozūraitis, Raimondas
    Stockholm University, Faculty of Science, Department of Zoology. Laboratory of Chemical and Behavioral Ecology, Institute of Ecology, Nature Research Centre, Lithuania.
    Servienė, E.
    Can crickets recognise bacterially contaminated feed? Gryllus assimilis odour perception of Escherichia coli2023In: Journal of Insects as Food and Feed, E-ISSN 2352-4588, Vol. 9, no 7, p. 947-954Article in journal (Refereed)
    Abstract [en]

    Edible crickets Acheta domesticus and Gryllus assimilis are worldwide mass-reared insects. They are recognised as a sustainable source of protein in the food and feed industries and, in relation to this, must comply with food safety requirements. In this study, we assessed the self-protective ability of crickets to recognise potentially hazardous bacteria-contaminated feed. A two-choice test was carried out to estimate the crickets’ preference between the bacteria-contaminated and control feed. Three bacterial species were tested as potential contaminants: Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis. A. domesticus did not recognise feed contaminated with any of the bacterial species tested. G. assimilis avoided E. coli-contaminated feed, while the other two bacteria did not cause differences in feeding behaviour. The study of gas chromatography-electroantennogram detection showed that E. coli released a volatile compound, which was olfactory perceived by both males and females of G. assimilis. The compound was identified as indole. In a behavioural test, crickets spent less time feeding on indole-contaminated feed compared to control feed. Hence, indole induced an avoidance response in G. assimilis. It can be concluded that G. assimilis perceives and recognises some bacteria contaminants and thereby avoids spoiled feed.

      

  • 32. Alexander, Jodi L.
    et al.
    Oliphant, Andrew
    Wilcockson, David C.
    Brendler-Spaeth, Timothy
    Dircksen, Heinrich
    Stockholm University, Faculty of Science, Department of Zoology, Functional Morphology.
    Webster, Simon G.
    Pigment dispersing factors and their cognate receptors in a crustacean model, with new insights into distinct neurons and their functions2020In: Frontiers in Neuroscience, ISSN 1662-4548, E-ISSN 1662-453X, Vol. 14, article id 595648Article in journal (Refereed)
    Abstract [en]

    Pigment dispersing factors (PDFs, or PDHs in crustaceans) form a structurally related group of neuropeptides found throughout the Ecdysozoa and were first discovered as pigmentary effector hormones in crustaceans. In insects PDFs fulfill crucial neuromodulatory roles, most notably as output regulators of the circadian system, underscoring their central position in physiological and behavioral organization of arthropods. Intriguingly, decapod crustaceans express multiple isoforms of PDH originating from separate genes, yet their differential functions are still to be determined. Here, we functionally define two PDH receptors in the crab Carcinus maenas and show them to be selectively activated by four PDH isoforms: PDHR 43673 was activated by PDH-1 and PDH-2 at low nanomolar doses whilst PDHR 41189 was activated by PDH-3 and an extended 20 residue e-PDH. Detailed examination of the anatomical distribution of all four peptides and their cognate receptors indicate that they likely perform different functions as secreted hormones and/or neuromodulators, with PDH-1 and its receptor 43,673 implicated in an authentic hormonal axis. PDH-2, PDH-3, and e-PDH were limited to non-neurohemal interneuronal sites in the CNS; PDHR 41189 was largely restricted to the nervous system suggesting a neuromodulatory function. Notably PDH-3 and e-PDH were without chromatophore dispersing activity. This is the first report which functionally defines a PDHR in an endocrine system in a crustacean and to indicate this and other putative roles of this physiologically pivotal peptide group in these organisms. Thus, our findings present opportunities to further examine the endocrine and circadian machinery in this important arthropod phylum.

  • 33. Allendorf, Fred
    et al.
    Ryman, Nils
    Stockholm University, Faculty of Science, Department of Zoology.
    The role of genetics in population viability analysis2002In: Population Viability Analysis / [ed] Beissinger,S.R. and McCullough,D.R., Chicago: University of Chicago Press , 2002, p. 50-85Chapter in book (Other academic)
  • 34. Allendorf, Fred W.
    et al.
    Berry, Oliver
    Ryman, Nils
    Stockholm University, Faculty of Science, Department of Zoology.
    So long to genetic diversity, and thanks for all the fish2014In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 23, no 1, p. 23-25Article in journal (Other academic)
    Abstract [en]

    The world faces a global fishing crisis. Wild marine fisheries comprise nearly 15% of all animal protein in the human diet, but, according to the U.N. Food and Agriculture Organization, nearly 60% of all commercially important marine fish stocks are overexploited, recovering, or depleted (FAO 2012; Fig. 1). Some authors have suggested that the large population sizes of harvested marine fish make even collapsed populations resistant to the loss of genetic variation by genetic drift (e. g. Beverton 1990). In contrast, others have argued that the loss of alleles because of overfishing may actually be more dramatic in large populations than in small ones (Ryman et al. 1995). In this issue, Pinsky & Palumbi (2014) report that overfished populations have approximately 2% lower heterozygosity and 12% lower allelic richness than populations that are not overfished. They also performed simulations which suggest that their estimates likely underestimate the actual loss of rare alleles by a factor of three or four. This important paper shows that the harvesting of marine fish can have genetic effects that threaten the long-term sustainability of this valuable resource.

  • 35. Allendorf, Fred W
    et al.
    England, Phillip R
    Luikart, Gordon
    Ritchie, Peter A
    Ryman, Nils
    Stockholm University, Faculty of Science, Department of Zoology.
    Genetic effects of harvest on wild animal populations.2008In: Trends Ecol Evol, ISSN 0169-5347, Vol. 23, no 6, p. 327-37Article in journal (Refereed)
    Abstract [en]

    Human harvest of animals in the wild occurs in terrestrial and aquatic habitats throughout the world and is often intense. Harvest has the potential to cause three types of genetic change: alteration of population subdivision, loss of genetic variation, and selective genetic changes. To sustain the productivity of harvested populations, it is crucial to incorporate genetic considerations into management. Nevertheless, it is not necessary to disentangle genetic and environmental causes of phenotypic changes to develop management plans for individual species. We recommend recognizing that some genetic change due to harvest is inevitable. Management plans should be developed by applying basic genetic principles combined with molecular genetic monitoring to minimize harmful genetic change.

  • 36.
    Alm Bergvall, Ulrika
    Stockholm University, Faculty of Science, Department of Zoology. Etologi.
    Development of feeding selectivity and behavioural syndromes in fallow deer2007In: Book of abstracts of the International Union of Game Biologists XXVIII Congress., 2007, p. 106-Conference paper (Refereed)
  • 37.
    Alm Bergvall, Ulrika
    Stockholm University, Faculty of Science, Department of Zoology. Etologi.
    Development of feeding selectivity in fallow deer: evolutionary and ethological implications2007In: Proceedings of the 19th Nordic Symposium of the International Society for Applied Ethology, 2007Conference paper (Other academic)
  • 38.
    Alm Bergvall, Ulrika
    Stockholm University, Faculty of Science, Department of Zoology.
    Food choice in fallow deer – experimental studies of selectivity2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, I experimentally investigate feeding selectivity in fallow deer (Dama dama), with respect to plant secondary compounds, especially tannins, which can decrease the quality of foods. I found that fallow deer avoided foods with higher amounts of tannic acid and Quebracho tannin, even though the deer ate some high-tannin food. The food choice was strongly dependent on the context in which the food was presented, so that the food choice in relation to tannin content was relative rather than absolute. When high-tannin food occurred at low frequency, the deer ate proportionally less from this type of food, at least when the difference in tannin content between the two foods was large. A basic implication is that an unpalatable plant type could benefit from its unpalatability, especially when occurring at low frequency. In experiments with two patches, the finding of a stronger within- than between-patch selectivity was mirrored in associational effects. First, low-tannin, palatable food was more eaten when occurring in a high-tannin patch, which corresponds to neighbour contrast susceptibility. Second, high-tannin, unpalatable food in a less defended patch was less eaten, which corresponds to neighbour contrast defence. A proximate cause of the associational effects can be the presence of a simultaneous negative contrast, which was experimentally demonstrated in an additional study. Individual differences in selectivity were present early in life and were consistent over five years, and selectivity was correlated with foraging exploratory behaviour. The results from this thesis suggest that fallow deer are selective in their food choice with respect to tannins from the beginning, and that the frequency of occurrence of different foods, but also the distance between foods and the complexity of presentation, influence the food choice. It is also suggested that a foraging behavioural syndrome is present in mammalian herbivores.

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  • 39.
    Alm Bergvall, Ulrika
    et al.
    Stockholm University, Faculty of Science, Department of Zoology. Swedish University of Agricultural Sciences, Sweden.
    Svensson, Lisa
    Kjellander, Petter
    Vigilance adjustments in relation to long- and short term risk in wild fallow deer (Dama dama)2016In: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 128, p. 58-63Article in journal (Refereed)
    Abstract [en]

    The risk allocation hypothesis predicts that vigilance should be adjusted to the temporal variation in risk. We test this hypothesis in wild fallow deer exposed to short term (disturbance) and long term (presence of a fawn after parturition) changes in risk. We recorded the proportion, frequency and type of vigilance and size of used area before and after parturition, in GPS-collared wild female fallow deer. Vigilance was divided in two main groups: non-grazing vigilance and grazing vigilance. The latter group was divided into grazing vigilance while chewing and a grazing vigilance when chewing was interrupted. By recording external disturbance in form of passing cars, we were able to investigate if this altered the amount, and type of vigilance. We found that females increased the proportion and frequency of grazing vigilance stop chewing after parturition. The grazing vigilance chewing was unaffected, but non-grazing vigilance decreased. Disturbance increased the proportion grazing vigilance stop chewing to the same extent before and after parturition. We found a clear decrease in female home range size after parturition as a possible behavioural adjustment. The increase in grazing vigilance stop chewing after parturition is a rarely described but expected cost of reproduction.

  • 40.
    Alm, Ulrika
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Birgersson, Björn
    Leimar, Olof
    The effect of food quality and relative abundance on food choice in fallow deer2002In: Animal Behaviour, ISSN 0003-3472, Vol. 64, no 3, p. 439-445Article in journal (Refereed)
  • 41.
    Alm, Ulrika
    et al.
    Stockholm University, Faculty of Science, Department of Zoology. Etologi.
    Leimar, Olof
    Stockholm University, Faculty of Science, Department of Zoology. Etologi.
    The effect of food quality and relative abundance on food choice in fallow deer2002In: Animal Behaviour, Vol. 64, p. 439-445Article in journal (Refereed)
  • 42.
    Almbro, Maria
    Stockholm University, Faculty of Science, Department of Zoology.
    Escape flight in butterflies2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Flight is considered to be the overarching reason for the enormous diversity and world-wide abundance of insects. Not only does flight enable great distances to be covered and new areas to be colonised, flying has also evolved to be important in most adult life-history characteristics from reproduction to anti-predator strategies. However, despite its advantages, the costs of flight are high, particularly with regard to building a flight apparatus and staying in the air. Winged insects are popular prey for various predators from which they rely on flight to escape. However, because of their nutrient poor adult diet, butterflies are especially sensitive to the trade-off between flight and reproduction. Theory therefore predicts costs of physiological changes such as weight gain to be visible through altered aerial performance. Whereas insect flight has been extensively studied with regard to biomechanics, aerodynamics, dispersal and force production, little effort has been made to empirically study the relationship between escape strategies and weight loading, despite its value for survival and fitness. In this thesis a novel three-dimensional flight-recording set-up was used to study free flight ability in relation to natural weight loads in male and female Aglais urticae and Pieris napi butterflies. Weight loads consisted of ingested food, mate-carrying and reproductive mass, affecting wing loading and flight muscle ratio, key determinants of flight ability. Moreover, butterfly escape strategies were investigated through the use of model predators. The results showed that perceived predation risk affected butterfly flight behaviour, with greater speed being observed in attacked butterflies. Decreased flight muscle ratio after feeding resulted in slower escape flights in A. urticae, and impaired flight during mate-carrying in P. napi. Increased wing loading during reproduction in P. napi negatively affected male flight speed and female take-off angles. In summary, this thesis demonstrates that flight effort is context dependant and shows a trade-off between flight ability and longevity- and fitness related weight gain that may ultimately affect survival, mating success and energy expenditure.

  • 43.
    Almbro, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Zoology, Ethology.
    Kullberg, Cecilia
    Stockholm University, Faculty of Science, Department of Zoology, Ethology.
    Impaired escape flight ability in butterflies due to low flight muscle ratio prior to hibernation2008In: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 211, no 1, p. 24-28Article in journal (Refereed)
  • 44.
    Almbro, Maria
    et al.
    Centre for Evolutionary Biology, University of Western Australia.
    Kullberg, Cecilia
    Stockholm University, Faculty of Science, Department of Zoology, Ethology.
    Season, sex and flight muscle investment affect take-off performance in the hibernating small tortoiseshell butterfly Agalis urticae (Lepidoptera: Nymphalidae)2011In: The Journal of Research on the Lepidoptera, ISSN 0022-4324, Vol. 44, p. 77-84Article in journal (Refereed)
    Abstract [en]

    Flight ability is generally expected to increase with relative flight muscle mass. Changes in weight can therefore be expected to influence the capacity to rapidly take-off, which can determine mating success and predator avoidance. This study examined the influence of relative flight muscle mass, sex, and season on free take-off flight ability in a butterfly model (Aglais urticae) that undergoes adult winter hibernation. Mass change and take-off flight ability (velocity and take-off angle), was predicted to fluctuate with season (before, during and after hibernation) and sex (due to reproductive investment). Our results indeed showed changes in take-off ability in relation to both parameters. Females maintained velocity across seasons but reduced take-off angles during and after hibernation. Male flight speed increased during and after hibernation, whereas take-off angles were significantly reduced during hibernation. Finally, we showed that investment in relative flight muscle mass increased velocity in female, but not in male butterflies.

  • 45.
    Almbro, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Zoology. Stockholm University, Faculty of Science, Department of Zoology, Department of Ethology.
    Kullberg, Cecilia
    Stockholm University, Faculty of Science, Department of Zoology. Stockholm University, Faculty of Science, Department of Zoology, Department of Ethology. Stockholm University.
    The downfall of mating: the effect of mate-carrying and flight muscle ratio on the escape ability of a pierid butterfly2009In: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 63, no 3, p. 413-420Article in journal (Refereed)
  • 46.
    Almbro, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Kullberg, Cecilia
    Stockholm University, Faculty of Science, Department of Zoology.
    Weight Loading and Reproductive Status Affect the Flight Performance of Pieris napi Butterflies2012In: Journal of insect behavior, ISSN 0892-7553, E-ISSN 1572-8889, Vol. 25, no 5, p. 441-452Article in journal (Refereed)
    Abstract [en]

    Weight-induced mobility reductions can have dramatic fitness consequences and winged animals are especially sensitive to the trade-off between mass and locomotion. Data on how natural weight fluctuations influence a flying insect's ability to take off are scarce. We therefore quantified take-off flight ability in Pieris napi butterflies in relation to reproductive status. Take-off flight ability (velocity and take-off angle) under suboptimal temperature conditions was recorded with a 3D-tracking camera system and was predicted to decrease with relatively larger weight loads. Our results show that relatively larger weight loads generally reduce flight speed in male butterflies and lower take-off angles in females. However, despite having a lower wing loading, mated male butterflies flew slower than unmated males. Our study suggests that retention of weight loads associated with reproduction impairs insect flight performance.

  • 47. Alpedrinha, João
    et al.
    Rodrigues, Leonor R.
    Stockholm University, Faculty of Science, Department of Zoology. University of Lisbon, Portugal.
    Magalhaes, Sara
    Abbott, Jessica
    The virtues and limitations of exploring the eco-evolutionary dynamics of sexually selected traits2019In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 128, no 10, p. 1381-1389Article in journal (Refereed)
    Abstract [en]

    Most studies on eco-evolutionary feedbacks concern the influence of abiotic factors, or predator-prey and host-parasite interactions, while studies involving sexual interactions are lagging behind. This is at odds with the potential of these interactions to engage in such processes. Indeed, there is now ample evidence that sexual selection is affected by ecological change and that sexually selected traits can evolve rapidly, which may modify the ecological context of populations, and thus the selection pressures they will be exposed to. Here we review evidence for such eco-evolutionary processes. We discuss examples of eco-evolutionary change in an attempt to understand the challenges related with identifying and characterizing such processes. In particular, we focus on the challenges associated with accurately identifying the components of the feedback as well as their causal relation. Finally, we evaluate scenarios where understanding eco-evolutionary feedbacks of sexual selection may help us appreciate the effects of sexual selection in shaping evolutionary processes.

  • 48.
    Altizer, Sonia
    et al.
    Institute of Ecology, University of Georgia.
    Nunn, Charles L
    Max Planck Institute for Evolutionary Anthropology, Department of Integrative Biology, University of California, Berkeley.
    Lindenfors, Patrik
    Stockholm University, Faculty of Science, Department of Zoology. Stockholm University, Faculty of Humanities, Centre for the Study of Cultural Evolution.
    Do threatened hosts have fewer parasites?: A comparative study in primates2007In: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745, Vol. 76, p. 304-314Article in journal (Refereed)
    Abstract [en]

    1. Parasites and infectious diseases have become a major concern in conservation biology, in part because they can trigger or accelerate species or population declines. Focusing on primates as a well-studied host clade, we tested whether the species richness and prevalence of parasites differed between threatened and non-threatened host species.

    2. We collated data on 386 species of parasites (including viruses, bacteria, protozoa, helminths and arthropods) reported to infect wild populations of 36 threatened and 81 non-threatened primate species. Analyses controlled for uneven sampling effort and host phylogeny.

    3. Results showed that total parasite species richness was lower among threatened primates, supporting the prediction that small, isolated host populations harbour fewer parasite species. This trend was consistent across three major parasite groups found in primates (helminths, protozoa and viruses). Counter to our predictions, patterns of parasite species richness were independent of parasite transmission mode and the degree of host specificity.

    4. We also examined the prevalence of selected parasite genera among primate sister-taxa that differed in their ranked threat categories, but found no significant differences in prevalence between threatened and non-threatened hosts.

    5. This study is the first to demonstrate differences in parasite richness relative to host threat status. Results indicate that human activities and host characteristics that increase the extinction risk of wild animal species may lead simultaneously to the loss of parasites. Lower average parasite richness in threatened host taxa also points to the need for a better understanding of the cascading effects of host biodiversity loss for affiliated parasite species.

  • 49. Altstein, Miriam
    et al.
    Nässel, Dick R
    Stockholm University, Faculty of Science, Department of Zoology. Stockholm University, Faculty of Science, Department of Zoology, Functional Morphology.
    Neuropeptide signaling in insects.2010In: Neuropeptide systems as targets for parasite and pest control / [ed] Timothy G. Geary and Aaron G. Maule, New York: Springer Science+Business Media , 2010, Vol. 692, p. 155-65Chapter in book (Other academic)
    Abstract [en]

    Neuropeptides represent the largest single class of signal compounds and are involved in regulation of development, growth, reproduction, metabolism and behavior of insects. Over the last few years there has been a tremendous increase in our knowledge of neuropeptide signaling due to genome sequencing, peptidomics, gene micro arrays, receptor characterization and targeted gene interference combined with physiological and behavior analysis. In this chapter we review the current knowledge of structure and distribution of insect neuropeptides and their receptors, as well as their diverse functions. We also discuss peptide biosynthesis, processing and expression, as well as classification of insect neuropeptides. Special attention is paid to the role insect neuropeptides play as potential targets for pest management and as a basis for development of insect control agents employing the rational/structural design approaches.

  • 50.
    Amcoff, Mirjam
    et al.
    Uppsala University, Sweden.
    Kolm, Niclas
    Stockholm University, Faculty of Science, Department of Zoology.
    Multiple male sexual signals and female responsiveness in the swordtail characin, Corynopoma riisei2015In: Environmental Biology of Fishes, ISSN 0378-1909, E-ISSN 1573-5133, Vol. 98, no 7, p. 1731-1740Article in journal (Refereed)
    Abstract [en]

    In the courtship process, multiple signals are often used between the signaller and the receiver. Here we describe female response to multiple male visual morphological and behavioural signals in the swordtail characin, Corynopoma riisei. The swordtail characin is a species in which males display several morphological ornaments as well as a rich courtship repertoire. Our results show that high courtship intensity was associated with an increased female response towards the male ornament, increased number of mating attempts and a reduction in female aggression. The morphological aspects investigated here did not seem to correlate with female response. This may indicate that, when both behaviour and morphology are considered simultaneously, courtship behaviour may have priority over morphological cues in this species.

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