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  • 1551. Wong, B. B. M.
    et al.
    Svensson, P. Andreas
    School of Biological Sciences, Monash University, Melbourne, VIC, 3800, Australia.
    Strategic male signalling effort in a desert-dwelling fish2009Inngår i: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 63, nr 4, s. 543-549Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Males often use elaborate courtship displays to attract females for mating. Much attention, in this regard, has been focused on trying to understand the causes and consequences of signal variation among males. Far less, by contrast, is known about within-individual variation in signal expression and, in particular, the extent to which males may be able to strategically adjust their signalling output to try to maximise their reproductive returns. Here, we experimentally investigated male courtship effort in a fish, the Australian desert goby, Chlamydogobius eremius. When offered a simultaneous choice between a large and a small female, male gobies spent significantly more time associating with, and courting, the former, probably because larger females are also more fecund. Male signalling patterns were also investigated under a sequential choice scenario, with females presented one at a time. When first offered a female, male courtship was not affected by female size. However, males adjusted their courtship effort towards a second female depending on the size of the female encountered previously. In particular, males that were first offered a large female significantly reduced their courtship effort when presented with a subsequent, smaller, female. Our findings suggest that males may be able to respond adaptively to differences in female quality, and strategically adjust their signalling effort accordingly.

  • 1552.
    Wärmländer, Sebastian K. T. S.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för biokemi och biofysik.
    Sholts, Sabrina B.
    Erlandson, Jon M.
    Gjerdrum, Thor
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Ancient bitumen use and polycyclic aromatic hydrocarbons exposure: a potential factor in the health decline of prehistoric California Indians.2011Inngår i: American Journal of Physical Anthropology: Supplement: Program of the 80th Annual Meeting of the American Association of Physical Anthropologists, 2011, Vol. 144, s. vol 144-suppl.52Konferansepaper (Annet vitenskapelig)
  • 1553.
    Xenikoudakis, Georgios
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of National History, Sweden.
    Ersmark, Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Swedish Museum of National History, Sweden.
    Tison, J. -L.
    Waits, L.
    Kindberg, J.
    Swenson, J. E.
    Dalén, Love
    Swedish Museum of National History, Sweden.
    Consequences of a demographic bottleneck on geneticstructure and variation in the Scandinavian brown bear2015Inngår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 24, nr 13, s. 3441-3454Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Scandinavian brown bear went through a major decline in population size approximately 100years ago, due to intense hunting. After being protected, the population subsequently recovered and today numbers in the thousands. The genetic diversity in the contemporary population has been investigated in considerable detail, and it has been shown that the population consists of several subpopulations that display relatively high levels of genetic variation. However, previous studies have been unable to resolve the degree to which the demographic bottleneck impacted the contemporary genetic structure and diversity. In this study, we used mitochondrial and microsatellite DNA markers from pre- and postbottleneck Scandinavian brown bear samples to investigate the effect of the bottleneck. Simulation and multivariate analysis suggested the same genetic structure for the historical and modern samples, which are clustered into three subpopulations in southern, central and northern Scandinavia. However, the southern subpopulation appears to have gone through a marked change in allele frequencies. When comparing the mitochondrial DNA diversity in the whole population, we found a major decline in haplotype numbers across the bottleneck. However, the loss of autosomal genetic diversity was less pronounced, although a significant decline in allelic richness was observed in the southern subpopulation. Approximate Bayesian computations provided clear support for a decline in effective population size during the bottleneck, in both the southern and northern subpopulations. These results have implications for the future management of the Scandinavian brown bear because they indicate a recent loss in genetic diversity and also that the current genetic structure may have been caused by historical ecological processes rather than recent anthropogenic persecution.

  • 1554.
    Xiong, Ye
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för biologisk grundutbildning. Molecular Ecology and Evolution Lab , Lund University.
    Early dietary effects of arachidonic acid on gene expression linked to  immune response and metabolism in rural and urban Great Tit (Parus Major) nestlings2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This study was conducted to test the silver spoon hypothesis that earlylife nutritional conditions impact development, performance and fitness of the birdsgreat tit (Parus major) nestlings. We investigated whether fatty acid affects immunityand metabolism during the altricial period by examining the expressions of geneTLR4 (immunity related) and COX 2 (metabolism related) against a dietarymanipulation on great tit nestlings in urban vs. rural environments. The resultssuggested that arachidonic acid had no significant effect on TLR4 expression, but atendency to induce immune response, regardless of urban or rural conditions. Thestrength of immune response was however negatively correlated with laying date. Theurban great tit nestlings had a higher COX 2 gene expression than rural ones, andarachidonic acid suppressed COX 2.Thus no strong support to the hypothesis was found for the studied great titpopulations. It showed, however, i) there is a tendency of increasing immune responsewith extra fatty acid in the diet, and ii) arachidonic acid suppress metabolism. Fattyacid involved in a multiple physiological processes and this complex need to beelaborated in future studies.

  • 1555.
    Xu, Bo
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Evolutionary and Pharmacological Studies of NPY and QRFP Receptors2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The neuropeptide Y (NPY) system consists of 3-4 peptides and 4-7 receptors in vertebrates. It has powerful effects on appetite regulation and is involved in many other biological processes including blood pressure regulation, bone formation and anxiety. This thesis describes studies of the evolution of the NPY system by comparison of several vertebrate species and structural studies of the human Y2 receptor, which reduces appetite, to identify amino acid residues involved in peptide-receptor interactions.

    The NPY system was studied in zebrafish (Danio rerio), western clawed frog (Xenopus tropicalis), and sea lamprey (Petromyzon marinus). The receptors were cloned and functionally expressed and their pharmacological profiles were determined using the native peptides in either binding studies or a signal transduction assay. Some peptide-receptor preferences were observed, indicating functional specialization.

    A receptor family closely related to the NPY receptors, called the QRFP receptors, was investigated. A QRFP receptor was cloned from amphioxus, Branchistoma floridae, showing that the receptor arose before the origin of the vertebrates. Evolutionary studies demonstrated that the ancestral vertebrate had as many as four QRFP receptors, only one of which remains in mammals today. This correlates with the NPY receptor family, located in the same chromosomal regions, which had seven members in the ancestral vertebrate but only 4-5 in living mammals. Some vertebrates have considerably more complex NPY and QRFP receptor systems than humans and other mammals.

    Two studies investigated interactions of NPY-family peptides with the human Y2 receptor. Candidate residues, selected based on structural modeling and docking, were mutated to disrupt possible interactions with peptide ligands. The modified receptors were expressed in cultured cells and investigated by measuring binding and functional responses. Several receptor residues were found to influence peptide-receptor interactions, some of which are involved in maintaining receptor structure. In a pilot study, the kinetics of peptide-receptor interaction were found to be very slow, of the order several hours.

    In conclusion, this thesis clarifies evolutionary relationships for the complex NPY and QRFP peptide-receptor systems and improves the structural models of the human NPY-family receptors, especially Y2. These results will hopefully facilitate drug design for targeting of NPY-family receptors.

  • 1556.
    Xu, Bo
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Farmakologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Lagman, David
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Farmakologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Sundström, Görel
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Larhammar, Dan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Farmakologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Neuropeptide Y family receptors Y1 and Y2 from sea lamprey, Petromyzon marinus: cloning and pharmacological characterization2015Inngår i: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 222, s. 106-115Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    The vertebrate gene family for neuropeptide Y (NPY) receptors expanded by duplication of the chromosome carrying the ancestral Y1–Y2–Y5 gene triplet. After loss of some duplicates, the ancestral jawed vertebrate had seven receptor subtypes forming the Y1 (including Y1, Y4, Y6, Y8), Y2 (including Y2, Y7) and Y5 (only Y5) subfamilies. Lampreys are considered to have experienced the same chromosome duplications as gnathostomes and should also be expected to have multiple receptor genes. However, previously only a Y4-like and a Y5 receptor have been cloned and characterized. Here we report the cloning and characterization of two additional receptors from the sea lamprey Petromyzon marinus. Sequence phylogeny alone could not with certainty assign their identity, but based on synteny comparisons of P. marinus and the Arctic lamprey, Lethenteron camtschaticum, with jawed vertebrates, the two receptors most likely are Y1 and Y2. Both receptors were expressed in human HEK293 cells and inositol phosphate assays were performed to determine the response to the three native lamprey peptides NPY, PYY and PMY. The three peptides have similar potencies in the nanomolar range for Y1. No obvious response to the three peptides was detected for Y2. Synteny analysis supports identification of the previously cloned receptor as Y4. No additional NPY receptor genes could be identified in the presently available lamprey genome assemblies. Thus, four NPY-family receptors have been identified in lampreys, orthologs of the same subtypes as in humans (Y1, Y2, Y4 and Y5), whereas many other vertebrate lineages have retained additional ancestral subtypes.

  • 1557.
    Xu, Feifei
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi.
    Comparative Genomics in Diplomonads: Lifestyle Variations Revealed at Genetic Level2015Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    As sequencing technologies advance genome studies are becoming a basic tool for studying an organism, and with more genomes available comparative genomics is maturing into a powerful tool for biological research. This thesis demonstrates the strength of a comparative genomics approach on a group of understudied eukaryotes, the diplomonads.

    Diplomonads are a group of single cell eukaryotic flagellates living in oxygen-poor environments. Most diplomonads are intestinal parasites, like the well-studied human parasite Giardia intestinalis. There are seven different G. intestinalis assemblages (genotypes) affecting different hosts, and it’s under debate whether these are one species. A genome-wide study of three G. intestinalis genomes from different assemblages reveals little inter-assemblage sexual recombination, supporting that the different G. intestinalis assemblages are genetically isolated and thus different species.

    A genomic comparison between the fish parasite S. salmonicida and G. intestinalis reveals genetic differences reflecting differences in their parasitic lifestyles. There is a tighter transcriptional regulation and a larger metabolic reservoir in S. salmonicida, likely adaptations to the fluctuating environments it encounters during its systemic infection compared to G. intestinalis which is a strict intestinal parasite.

    The S. salmonicida genome analysis also discovers genes involved in energy metabolism. Some of these are experimentally shown to localize to mitochondrion-related organelles in S. salmonicida, indicating that they possess energy-producing organelles that should be classified as hydrogenosomes, as opposed to the mitosomes in G. intestinalis.

    A transcriptome analysis of the free-living Trepomonas is compared with genomic data from the two parasitic diplomonads. The majority of the genes associated with a free-living lifestyle, like phagocytosis and a larger metabolic capacity, are of prokaryotic origin. This suggests that the ancestor of the free-living diplomonad was likely host-associated and that the free-living lifestyle is a secondary adaptation acquired through horizontal gene transfers. 

    In conclusion, this thesis uses different comparative genomics approaches to broaden the knowledge on diplomonad diversity and to provide more insight into how the lifestyle differences are reflected on the genetic level. The bioinformatics pipelines and expertise gained in these studies will be useful in other projects in diplomonads and other organismal groups.

  • 1558.
    Xu, Feifei
    et al.
    Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Jerlström-Hultqvist, Jon
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Kolisko, Martin
    Dalhousie Univ, Dept Biol, Halifax, NS, Canada; Dalhousie Univ, Dept Biochem & Mol Biol, Halifax, NS, Canada; Univ British Columbia, Dept Bot, Vancouver, BC, Canada.
    Simpson, Alastair G. B.
    Dalhousie Univ, Dept Biol, Halifax, NS, Canada; Canadian Inst Adv Res, Integrated Microbial Biodivers Program, Toronto, ON, Canada.
    Roger, Andrew J.
    Dalhousie Univ, Dept Biochem & Mol Biol, Halifax, NS, Canada; anadian Inst Adv Res, Integrated Microbial Biodivers Program, Toronto, ON, Canada.
    Svärd, Staffan G.
    Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Andersson, Jan O.
    Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    On the reversibility of parasitism: adaptation to a free-living lifestyle via gene acquisitions in the diplomonad Trepomonas sp PC12016Inngår i: BMC Biology, ISSN 1741-7007, E-ISSN 1741-7007, Vol. 14, artikkel-id 62Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: It is generally thought that the evolutionary transition to parasitism is irreversible because it is associated with the loss of functions needed for a free-living lifestyle. Nevertheless, free-living taxa are sometimes nested within parasite clades in phylogenetic trees, which could indicate that they are secondarily free-living. Herein, we test this hypothesis by studying the genomic basis for evolutionary transitions between lifestyles in diplomonads, a group of anaerobic eukaryotes. Most described diplomonads are intestinal parasites or commensals of various animals, but there are also free-living diplomonads found in oxygen-poor environments such as marine and freshwater sediments. All these nest well within groups of parasitic diplomonads in phylogenetic trees, suggesting that they could be secondarily free-living. Results: We present a transcriptome study of Trepomonas sp. PC1, a diplomonad isolated from marine sediment. Analysis of the metabolic genes revealed a number of proteins involved in degradation of the bacterial membrane and cell wall, as well as an extended set of enzymes involved in carbohydrate degradation and nucleotide metabolism. Phylogenetic analyses showed that most of the differences in metabolic capacity between free-living Trepomonas and the parasitic diplomonads are due to recent acquisitions of bacterial genes via gene transfer. Interestingly, one of the acquired genes encodes a ribonucleotide reductase, which frees Trepomonas from the need to scavenge deoxyribonucleosides. The transcriptome included a gene encoding squalene-tetrahymanol cyclase. This enzyme synthesizes the sterol substitute tetrahymanol in the absence of oxygen, potentially allowing Trepomonas to thrive under anaerobic conditions as a free-living bacterivore, without depending on sterols from other eukaryotes. Conclusions: Our findings are consistent with the phylogenetic evidence that the last common ancestor of diplomonads was dependent on a host and that Trepomonas has adapted secondarily to a free-living lifestyle. We believe that similar studies of other groups where free-living taxa are nested within parasites could reveal more examples of secondarily free-living eukaryotes.

  • 1559.
    Yazdi, Homa Papoli
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Ellegren, Hans
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Old but Not (So) Degenerated-Slow Evolution of Largely Homomorphic Sex Chromosomes in Ratites2014Inngår i: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 31, nr 6, s. 1444-1453Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Degeneration of the nonrecombining chromosome is a common feature of sex chromosome evolution, readily evident by the presence of a pair of largely heteromorphic chromosomes, like in eutherian mammals and birds. However, in ratites (order Palaeognathae, including, e.g., ostrich), the Z and W chromosomes are similar in size and largely undifferentiated, despite avian sex chromosome evolution was initiated > 130 Ma. To better understand what may limit sex chromosome evolution, we performed ostrich transcriptome sequencing and studied genes from the nonrecombining region of the W chromosome. Fourteen gametologous gene pairs present on the W chromosome and Z chromosome were identified, with synonymous sequence divergence of 0.027-0.177. The location of these genes on the Z chromosome was consistent with a sequential increase in divergence, starting 110-157 and ending 24-30 Ma. On the basis of the occurrence of Z-linked genes hemizygous in females, we estimate that about one-third of the Z chromosome does not recombine with the W chromosome in female meiosis. Pairwise d(N)/d(S) between gametologs decreased with age, suggesting strong evolutionary constraint in old gametologs. Lineage-specific d(N)/d(S) was consistently higher in W-linked genes, in accordance with the lower efficacy of selection expected in nonrecombining chromosomes. A higher ratio of GC > AT:AT > GC substitutions in W-linked genes supports a role for GC-biased gene conversion in differentially driving base composition on the two sex chromosomes. A male-to-female (M:F) expression ratio of close to one for recombining genes and close to two for Z-linked genes lacking a W copy show that dosage compensation is essentially absent. Some gametologous genes have retained active expression of the W copy in females (giving a M:F ratio of 1 for the gametologous gene pair), whereas for others W expression has become severely reduced resulting in a M:F ratio of close to 2. These observations resemble the patterns of sex chromosome evolution seen in other avian and mammalian lineages, suggesting similar underlying evolutionary processes, although the rate of sex chromosome differentiation has been atypically low. Lack of dosage compensation may be a factor hindering sex chromosome evolution in this lineage.

  • 1560. Young, Briana
    et al.
    Ghirlanda, Stefano
    Stockholms universitet, Humanistiska fakulteten, Centrum för evolutionär kulturforskning. Brooklyn College, USA.
    Grasso, Frank W.
    Parallel Implementation of Instinctual and Learning Neural Mechanisms in a Simulated Mobile Robot2012Inngår i: Biomimetic and Biohybrid Systems: Living machines / [ed] Tony J. Prescott, Nathan F. Lepora, Anna Mura, Paul F. M. J. Verschure, 2012, s. 298-308Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The question of how biological learning and instinctive neural mechanisms interact with each other in the course of development to produce novel, adaptive behaviors was explored via a robotic simulation. Instinctive behavior in the agent was implemented in a hard-wired network which produced obstacle avoidance. Phototactic behavior was produced in two serially connected plastic layers. A self-organizing feature map was combined with a reinforcement learning layer to produce a learning network. The reinforcement came from an internally generated signal. Both the adaptive and fixed networks supplied motor control signals to the robot motors. The sizes of the self-organizing layer, reinforcement layer, and the complexity of the environment were varied and effects on robot phototactic efficiency and accuracy in the mature networks were measured. A significant interaction of the three independent variables was found, supporting the idea that organisms evolve distinct combinations of instinctive and plastic neural mechanisms which are tailored to the demands of the environment in which their species evolved.

  • 1561.
    Zajitschek, Felix
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Zajitschek, Susanne R. K
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Canton, Cindy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Georgolopoulos, Grigorios
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Friberg, Urban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Maklakov, Alexei A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Evolution under dietary restriction increases male reproductive performance without survival cost2016Inngår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 283, nr 1825, artikkel-id 20152726Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dietary restriction (DR), a reduction in nutrient intake without malnutrition, is the most reproducible way to extend lifespan in a wide range of organisms across the tree of life, yet the evolutionary underpinnings of the DR effect on lifespan are still widely debated. The leading theory suggests that this effect is adaptive and results from reallocation of resources from reproduction to somatic maintenance, in order to survive periods of famine in nature. However, such response would cease to be adaptive when DR is chronic and animals are selected to allocate more resources to reproduction. Nevertheless, chronic DR can also increase the strength of selection resulting in the evolution of more robust genotypes. We evolved Drosophila melanogaster fruit flies on ‘DR’, ‘standard’ and ‘high’ adult diets in replicate populations with overlapping generations. After approximately 25 generations of experimental evolution, male ‘DR’ flies had higher fitness than males from ‘standard’ and ‘high’ populations. Strikingly, this increase in reproductive success did not come at a cost to survival. Our results suggest that sustained DR selects for more robust male genotypes that are overall better in converting resources into energy, which they allocate mostly to reproduction.

  • 1562.
    Zajitschek, Felix
    et al.
    Department of Animal Ecology, Ageing Research Group, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
    Zajitschek, Susanne R. K.
    Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
    Friberg, Urban
    Department of Evolutionary Biology, Ageing Research Group, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
    Maklakov, Alexei A.
    Department of Animal Ecology, Ageing Research Group, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
    Interactive effects of sex, social environment, dietary restriction, and methionine on survival and reproduction in fruit flies2013Inngår i: Age (Omaha), ISSN 0161-9152, E-ISSN 1574-4647, Vol. 35, nr 4, s. 1193-1204Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    For the evolution of life histories, the trade-off between survival and reproduction is fundamental. Because sexes optimize fitness in different ways, this trade-off is expected to be resolved differently by males and females. Consequently, the sexes are predicted to respond differently to changes in resource availability. In fruit flies, research on dietary restriction has focused largely on females maintained in the absence of males, thereby neglecting sexual interactions that affect reproductive behavior of both sexes under more natural conditions. Here, we tested for the interactive effects of diet (40, 60, 100, and 300 % of standard yeast concentrations) and social environment (separate-sex vs. mixed-sex groups) on male and female Drosophila melanogaster life histories. Additionally, we evaluated the essential amino acid methionine as an agent that can uncouple the survival-reproduction trade-off. We show sex differences in the effect of social environment on survival patterns, but not on reproductive fitness. In females, yeast had a positive effect on reproduction and a negative effect on survival. In males, yeast had a negative effect on reproduction and the effect on survival depended on the social environment. Methionine reduced survival, but had no effect on reproduction. Our findings highlight the need to include both sexes and to vary social environments in research programs aimed at lifespan extension and call for further evaluation of the fecundity-restoring effect of methionine.

  • 1563.
    Zajitschek, Susanne
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi. Univ East Anglia, Sch Biol Sci, Norwich Res Pk, Norwich NR4 7TJ, Norfolk, England.;CSIC, EBD, Donana Biol Stn, C Americo Vespucio S-N, Seville 41092, Spain..
    Herbert-Read, James E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Tillämpad matematik och statistik. Stockholm Univ, Dept Zool, S-10691 Stockholm, Sweden..
    Abbasi, Nasir M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik. Univ East Anglia, Sch Biol Sci, Norwich Res Pk, Norwich NR4 7TJ, Norfolk, England.
    Zajitschek, Felix
    Monash Univ, Sch Biol Sci, Bldg 18, Clayton, Vic 3800, Australia..
    Immler, Simone
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi. Univ East Anglia, Sch Biol Sci, Norwich Res Pk, Norwich NR4 7TJ, Norfolk, England.
    Paternal personality and social status influence offspring activity in zebrafish2017Inngår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 17, artikkel-id 157Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Evidence for the transmission of non-genetic information from father to offspring is rapidly accumulating. While the impact of chemical and physical factors such as toxins or diet on the fitness of the parents and their offspring have been studied extensively, the importance of behavioural and social circumstances has only recently been recognised. Behavioural traits such as personality characteristics can be relatively stable, and partly comprise a genetic component but we know little about the non-genetic transmission of plastic behavioural traits from parents to offspring. We investigated the relative effect of personality and of social dominance as indicators at the opposite ends of the plasticity range on offspring behaviour in the zebrafish (Danio rerio). We assessed male boldness, a behavioural trait that has previously been shown previously to possess genetic underpinnings, and experimentally manipulated male social status to assess the association between the two types of behaviour and their correlation with offspring activity. Results: We found a clear interaction between the relatively stable and putative genetic effects based on inherited differences in personality and the experimentally induced epigenetic effects from changes in the social status of the father on offspring activity. Conclusions: Our study shows that offspring behaviour is determined by a combination of paternal personality traits and on-genetic effects derived from the social status of the father.

  • 1564.
    Zajitschek, Susanne
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Hotzy, Cosima
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Zajitschek, Felix
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Immler, Simone
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Short-term variation in sperm competition causes sperm-mediated epigenetic effects on early offspring performance in the zebrafish2014Inngår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 281, nr 1785, s. 20140422-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The inheritance of non-genetic factors is increasingly seen to play a major role in ecology and evolution. While the causes and consequences of epigenetic effects transmitted from the mother to the offspring have received ample attention, much less is known about how variation in the condition of the father affects the offspring. Here, we manipulated the intensity of sperm competition experienced by male zebrafish Danio rerio to investigate the potential for sperm-mediated epigenetic effects over a relatively short period of time. We found that the rapid responses of males to varying intensity of sperm competition not only affected sperm traits as shown previously, but also the performance of the resulting offspring. We observed that males exposed to high intensity of sperm competition produced faster swimming and more motile sperm, and sired offspring that hatched over a narrower time frame but exhibited a lower survival rate than males exposed to low intensity of sperm competition. Our results provide striking evidence for short-term paternal effects and the possible fitness consequences of such sperm-mediated non-genetic factors not only for the resulting offspring but also for the female.

  • 1565. Zamora, Samuel
    et al.
    Lefebvre, Bertrand
    Hosgör, Izzet
    Franzén, Christina
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Nardin, Elise
    Fatka, Oldřich
    Álvaro, José Javier
    The Cambrian edrioasteroid Stromatocystites (Echinodermata): Systematics, palaeogeography, and palaeoecology.2015Inngår i: Geobios, ISSN 0016-6995, E-ISSN 1777-5728, Vol. 48, nr 5, s. 417-426Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Cambrian edrioasteroid Stromatocystites is reported and described from Spain, Sweden and Turkey. All previously known occurrences of the genus are critically reviewed, and S. flexibilis is reinterpreted as a junior synonym of S. pentangularis. Stromatocystites was biogeographically widespread and colonized different areas of Baltica, Gondwana (Arabian, eastern and western margins) and Laurentia (western Newfoundland). Stratigraphically, it ranges from Cambrian Series 2, Stage 4 to Cambrian Series 3, Drumian. Stromatocystites lived in quiet water environments with stabilized substrates. It was attached directly to the substrate by its aboral surface. As these environments were widespread throughout Baltica, Gondwana and Laurentia, availability of suitable substrates for larval settlement and oceanic palaeocurrents led to the successful development of Stromatocystites colonies.

  • 1566.
    Zaremba-Niedzwiedzka, Katarzyna
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Fernández Cáceres, Eva
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Saw, Jimmy Hser Wah
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Bäckström, Disa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Juzokaite, Lina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Vancaester, Emmelien
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab. Univ Ghent, Dept Plant Syst Biol, VIB, Technol Pk 927, B-9052 Ghent, Belgium.;Univ Ghent, Dept Plant Biotechnol & Bioinformat, Technol Pk 927, B-9052 Ghent, Belgium..
    Seitz, Kiley W.
    Univ Texas Austin, Inst Marine Sci, Dept Marine Sci, Port Aransas, TX 78373 USA..
    Anantharaman, Karthik
    Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA..
    Starnawski, Piotr
    Aarhus Univ, Sect Microbiol, DK-8000 Aarhus, Denmark.;Aarhus Univ, Ctr Geomicrobiol, Dept Biosci, DK-8000 Aarhus, Denmark..
    Kjeldsen, Kasper U.
    Aarhus Univ, Sect Microbiol, DK-8000 Aarhus, Denmark.;Aarhus Univ, Ctr Geomicrobiol, Dept Biosci, DK-8000 Aarhus, Denmark..
    Stott, Matthew B.
    Extremophile Res Grp, GNS Sci, Private Bag 2000, Taupo 3352, New Zealand..
    Nunoura, Takuro
    Japan Agcy Marine Earth Sci & Technol, Res & Dev Ctr Marine Biosci, Yokosuka, Kanagawa 2370061, Japan..
    Banfield, Jillian F.
    Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA 94720 USA.;Univ Calif Berkeley, Dept Environm Sci Policy & Management, Berkeley, CA 94720 USA..
    Schramm, Andreas
    Aarhus Univ, Sect Microbiol, DK-8000 Aarhus, Denmark.;Aarhus Univ, Ctr Geomicrobiol, Dept Biosci, DK-8000 Aarhus, Denmark..
    Baker, Brett J.
    Univ Texas Austin, Inst Marine Sci, Dept Marine Sci, Port Aransas, TX 78373 USA..
    Spang, Anja
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Asgard archaea illuminate the origin of eukaryotic cellular complexity2017Inngår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 541, nr 7637, s. 353-+Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The origin and cellular complexity of eukaryotes represent a major enigma in biology. Current data support scenarios in which an archaeal host cell and an alphaproteobacterial (mitochondrial) endosymbiont merged together, resulting in the first eukaryotic cell. The host cell is related to Lokiarchaeota, an archaeal phylum with many eukaryotic features. The emergence of the structural complexity that characterizes eukaryotic cells remains unclear. Here we describe the 'Asgard' superphylum, a group of uncultivated archaea that, as well as Lokiarchaeota, includes Thor-, Odin- and Heimdallarchaeota. Asgard archaea affiliate with eukaryotes in phylogenomic analyses, and their genomes are enriched for proteins formerly considered specific to eukaryotes. Notably, thorarchaeal genomes encode several homologues of eukaryotic membrane-trafficking machinery components, including Sec23/24 and TRAPP domains. Furthermore, we identify thorarchaeal proteins with similar features to eukaryotic coat proteins involved in vesicle biogenesis. Our results expand the known repertoire of 'eukaryote-specific' proteins in Archaea, indicating that the archaeal host cell already contained many key components that govern eukaryotic cellular complexity.

  • 1567. Zhang, Chi
    et al.
    Stadler, Tanja
    Klopfstein, Seraina
    Heath, Tracy A.
    Ronquist, Fredrik
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Total-evidence dating under the fossilized birth–death process2016Inngår i: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 65, nr 2, s. 228-249Artikkel i tidsskrift (Fagfellevurdert)
  • 1568. Zhang, Guojie
    et al.
    Li, Cai
    Li, Qiye
    Li, Bo
    Larkin, Denis M.
    Lee, Chul
    Storz, Jay F.
    Antunes, Agostinho
    Greenwold, Matthew J.
    Meredith, Robert W.
    Ödeen, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Cui, Jie
    Zhou, Qi
    Xu, Luohao
    Pan, Hailin
    Wang, Zongji
    Jin, Lijun
    Zhang, Pei
    Hu, Haofu
    Yang, Wei
    Hu, Jiang
    Xiao, Jin
    Yang, Zhikai
    Liu, Yang
    Xie, Qiaolin
    Yu, Hao
    Lian, Jinmin
    Wen, Ping
    Zhang, Fang
    Li, Hui
    Zeng, Yongli
    Xiong, Zijun
    Liu, Shiping
    Zhou, Long
    Huang, Zhiyong
    An, Na
    Wang, Jie
    Zheng, Qiumei
    Xiong, Yingqi
    Wang, Guangbiao
    Wang, Bo
    Wang, Jingjing
    Fan, Yu
    da Fonseca, Rute R.
    Alfaro-Nunez, Alonzo
    Schubert, Mikkel
    Orlando, Ludovic
    Mourier, Tobias
    Howard, Jason T.
    Ganapathy, Ganeshkumar
    Pfenning, Andreas
    Whitney, Osceola
    Rivas, Miriam V.
    Hara, Erina
    Smith, Julia
    Farre, Marta
    Narayan, Jitendra
    Slavov, Gancho
    Romanov, Michael N.
    Borges, Rui
    Machado, Joao Paulo
    Khan, Imran
    Springer, Mark S.
    Gatesy, John
    Hoffmann, Federico G.
    Opazo, Juan C.
    Hastad, Olle
    Sawyer, Roger H.
    Kim, Heebal
    Kim, Kyu-Won
    Kim, Hyeon Jeong
    Cho, Seoae
    Li, Ning
    Huang, Yinhua
    Bruford, Michael W.
    Zhan, Xiangjiang
    Dixon, Andrew
    Bertelsen, Mads F.
    Derryberry, Elizabeth
    Warren, Wesley
    Wilson, Richard K.
    Li, Shengbin
    Ray, David A.
    Green, Richard E.
    O'Brien, Stephen J.
    Griffin, Darren
    Johnson, Warren E.
    Haussler, David
    Ryder, Oliver A.
    Willerslev, Eske
    Graves, Gary R.
    Alstroem, Per
    Fjeldsa, Jon
    Mindell, David P.
    Edwards, Scott V.
    Braun, Edward L.
    Rahbek, Carsten
    Burt, David W.
    Houde, Peter
    Zhang, Yong
    Yang, Huanming
    Wang, Jian
    Jarvis, Erich D.
    Gilbert, M. Thomas P.
    Wang, Jun
    Comparative genomics reveals insights into avian genome evolution and adaptation2014Inngår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 346, nr 6215, s. 1311-1320Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits.

  • 1569.
    Zhang, Lai
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik. Technical University of Denmark, Denmark ; International Institute for Applied Systems Analysis, Laxenburg, Austria.
    Andersen, Ken H.
    Dieckmann, Ulf
    Brannstrom, Ake
    Four types of interference competition and their impacts on the ecology and evolution of size-structured populations and communities2015Inngår i: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 380, s. 280-290Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigate how four types of interference competition which alternatively affect foraging, metabolism, survival, and reproduction impact the ecology and evolution of size-structured populations. Even though all four types of interference competition reduce population biomass, interference competition at intermediate intensity sometimes significantly increases the abundance of adult individuals and the population's reproduction rate. We find that foraging and metabolic interference evolutionarily favor smaller maturation size when interference is weak and larger maturation size when interference is strong. The evolutionary response to survival interference and reproductive interference is always larger maturation size. We also investigate how the four types of interference competition impact the evolutionary dynamics and resultant diversity and trophic structure of size-structured communities. Like other types of trait-mediated competition, all four types of interference competition can induce disruptive selection and thus promote initial diversification. Even though foraging interference and reproductive interference are more potent in promoting initial diversification, they catalyze the formation of diverse communities with complex trophic structure only at high levels of interference intensity. By contrast, survival interference does so already at intermediate levels, while reproductive interference can only support relatively smaller communities with simpler trophic structure. Taken together, our results show how the type and intensity of interference competition jointly affect coexistence patterns in structured population models. (C) 2015 Elsevier Ltd. All rights reserved.

  • 1570. Zhang, Qu
    et al.
    Hill, Geoffrey E
    Edwards, Scott V
    Backström, Niclas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    A house finch (Haemorhous mexicanus) spleen transcriptome reveals intra- and interspecific patterns of gene expression, alternative splicing and genetic diversity in passerines.2014Inngår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 15, artikkel-id 305Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: With its plumage color dimorphism and unique history in North America, including a recent population expansion and an epizootic of Mycoplasma gallisepticum (MG), the house finch (Haemorhous mexicanus) is a model species for studying sexual selection, plumage coloration and host-parasite interactions. As part of our ongoing efforts to make available genomic resources for this species, here we report a transcriptome assembly derived from genes expressed in spleen.

    RESULTS: We characterize transcriptomes from two populations with different histories of demography and disease exposure: a recently founded population in the eastern US that has been exposed to MG for over a decade and a native population from the western range that has never been exposed to MG. We utilize this resource to quantify conservation in gene expression in passerine birds over approximately 50 MY by comparing splenic expression profiles for 9,646 house finch transcripts and those from zebra finch and find that less than half of all genes expressed in spleen in either species are expressed in both species. Comparative gene annotations from several vertebrate species suggest that the house finch transcriptomes contain ~15 genes not yet found in previously sequenced vertebrate genomes. The house finch transcriptomes harbour ~85,000 SNPs, ~20,000 of which are non-synonymous. Although not yet validated by biological or technical replication, we identify a set of genes exhibiting differences between populations in gene expression (n = 182; 2% of all transcripts), allele frequencies (76 FST ouliers) and alternative splicing as well as genes with several fixed non-synonymous substitutions; this set includes genes with functions related to double-strand break repair and immune response.

    CONCLUSIONS: The two house finch spleen transcriptome profiles will add to the increasing data on genome and transcriptome sequence information from natural populations. Differences in splenic expression between house finch and zebra finch imply either significant evolutionary turnover of splenic expression patterns or different physiological states of the individuals examined. The transcriptome resource will enhance the potential to annotate an eventual house finch genome, and the set of gene-based high-quality SNPs will help clarify the genetic underpinnings of host-pathogen interactions and sexual selection.

  • 1571. Zhang, Ruiying
    et al.
    Song, Gang
    Qu, Yanhua
    Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
    Alström, Per
    Ramos, Raül
    Xing, Xiaoying
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Fjeldså, Jon
    Wang, Haitao
    Yang, Xiaojun
    Kristin, Anton
    Shestopalov, Alexander M
    Choe, Jae Chun
    Lei, Fumin
    Comparative phylogeography of two widespread magpies: importance of habitat preference and breeding behavior on genetic structure in China.2012Inngår i: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 65, nr 2, s. 562-72Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Historical geological events and climatic changes are believed to have played important roles in shaping the current distribution of species. However, sympatric species may have responded in different ways to such climatic fluctuations. Here we compared genetic structures of two corvid species, the Azure-winged Magpie Cyanopica cyanus and the Eurasian Magpie Pica pica, both widespread but with different habitat dependence and some aspects of breeding behavior. Three mitochondrial genes and two nuclear introns were used to examine their co-distributed populations in East China and the Iberian Peninsula. Both species showed deep divergences between these two regions that were dated to the late Pliocene/early Pleistocene. In the East Chinese clade of C. cyanus, populations were subdivided between Northeast China and Central China, probably since the early to mid-Pleistocene, and the Central subclade showed a significant pattern of isolation by distance. In contrast, no genetic structure was found in the East China populations of P. pica. We suggest that the different patterns in the two species are at least partly explained by ecological differences between them, especially in habitat preference and perhaps also breeding behavior. These dissimilarities in life history traits might have affected the dispersal and survival abilities of these two species differently during environmental fluctuations.

  • 1572.
    Zhang, Zhifei
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Holmer, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Wang, Haizhou
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Butler, Aodhán D.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    An early Cambrian agglutinated tubular lophophorate with brachiopod characters2014Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 4, s. 4682-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The morphological disparity of lophotrochozoan phyla makes it difficult to predict the morphology of the last common ancestor. Only fossils of stem groups can help discover the morphological transitions that occurred along the roots of these phyla. Here, we describe a tubular fossil Yuganotheca elegans gen.et sp. nov. from the Cambrian (Stage 3) Chengjiang Lagerstätte (Yunnan, China) that exhibits an unusual combination of phoronid, brachiopod and tommotiid (Cambrian problematica) characters, notably a pair of agglutinated valves, enclosing a horseshoe-shaped lophophore, supported by a lower bipartite tubular attachment structure with a long coelomic pedicle providing anchorage. The discovery has important implications for the early evolution of lophotrochozoans, suggesting rooting of brachiopods into the sessile lophotrochozoans and the origination of their bivalved bauplan preceding the biomineralization of shell valves in crown brachiopods.

  • 1573. Zhao, Lei
    et al.
    Lascoux, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Overall, Andrew D. J.
    Waxman, David
    The characteristic trajectory of a fixing allele: a consequence of fictitious selection that arises from conditioning2013Inngår i: Genetics, ISSN 0016-6731, E-ISSN 1943-2631, Vol. 195, nr 2, s. 993-1006Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This work is concerned with the historical progression, to fixation, of an allele in a finite population. This progression is characterized by the average frequency trajectory of alleles that achieve fixation before a given time, T. Under a diffusion analysis, the average trajectory, conditional on fixation by time T, is shown to be equivalent to the average trajectory in an unconditioned problem involving additional selection. We call this additional selection “fictitious selection”; it plays the role of a selective force in the unconditioned problem but does not exist in reality. It is a consequence of conditioning on fixation. The fictitious selection is frequency dependent and can be very large compared with any real selection that is acting. We derive an approximation for the characteristic trajectory of a fixing allele, when subject to real additive selection, from an unconditioned problem, where the total selection is a combination of real and fictitious selection. Trying to reproduce the characteristic trajectory from the action of additive selection, in an infinite population, can lead to estimates of the strength of the selection that deviate from the real selection by >1000% or have the opposite sign. Strong evolutionary forces may be invoked in problems where conditioning has been carried out, but these forces may largely be an outcome of the conditioning and hence may not have a real existence. The work presented here clarifies these issues and provides two useful tools for future analyses: the characteristic trajectory of a fixing allele and the force that primarily drives this, namely fictitious selection. These should prove useful in a number of areas of interest including coalescence with selection, experimental evolution, time series analyses of ancient DNA, game theory in finite populations, and the historical dynamics of selected alleles in wild populations.

  • 1574.
    Zhao, Lei
    et al.
    Fudan Univ, Ctr Computat Syst Biol, 220 Handan Rd, Shanghai 200433, Peoples R China..
    Lascoux, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution. Fudan Univ, Ctr Computat Syst Biol, 220 Handan Rd, Shanghai 200433, Peoples R China..
    Waxman, David
    Fudan Univ, Ctr Computat Syst Biol, 220 Handan Rd, Shanghai 200433, Peoples R China..
    An informational transition in conditioned Markov chains: Applied to genetics and evolution2016Inngår i: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 402, s. 158-170Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work we assume that we have some knowledge about the state of a population at two known times, when the dynamics is governed by a Markov chain such as a Wright-Fisher model. Such knowledge could be obtained, for example, from observations made on ancient and contemporary DNA, or during laboratory experiments involving long term evolution. A natural assumption is that the behaviour of the population, between observations, is related to (or constrained by) what was actually observed. The present work shows that this assumption has limited validity. When the time interval between observations is larger than a characteristic value, which is a property of the population under consideration, there is a range of intermediate times where the behaviour of the population has reduced or no dependence on what was observed and an equilibrium-like distribution applies. Thus, for example, if the frequency of an allele is observed at two different times, then for a large enough time interval between observations, the population has reduced or no dependence on the two observed frequencies for a range of intermediate times. Given observations of a population at two times, we provide a general theoretical analysis of the behaviour of the population at all intermediate times, and determine an expression for the characteristic time interval, beyond which the observations do not constrain the population's behaviour over a range of intermediate times. The findings of this work relate to what can be meaningfully inferred about a population at intermediate times, given knowledge of terminal states.

  • 1575. Zhao, Wei
    et al.
    Meng, Jingxiang
    Wang, Baosheng
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Zhang, Lisha
    Xu, Yulan
    Zeng, Qing-Yin
    Li, Yue
    Mao, Jian-Feng
    Wang, Xiao-Ru
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Weak Crossability Barrier but Strong Juvenile Selection Supports Ecological Speciation of the Hybrid Pine Pinus Densata on the Tibetan Plateau2014Inngår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 68, nr 11, s. 3120-3133Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Determining how a new hybrid lineage can achieve reproductive isolation is a key to understanding the process and mechanisms of homoploid hybrid speciation. Here, we evaluated the degree and nature of reproductive isolation between the ecologically successful hybrid species Pinus densata and its parental species P. tabuliformis and P. yunnanensis. We performed interspecific crosses among the three species to assess their crossability. We then conducted reciprocal transplantation experiments to evaluate their fitness differentiation, and to examine how natural populations representing different directions of introgression differ in adaptation. The crossing experiments revealed weak genetic barriers among the species. The transplantation trials showed manifest evidence of local adaptation as the three species all performed best in their native habitats. Pinus densata populations from the western edge of its distribution have evolved a strong local adaptation to the specific habitat in that range; populations representing different directions of introgressants with the two parental species all showed fitness disadvantages in this P. densata habitat. These observations illustrate that premating isolation through selection against immigrants from other habitat types or postzygotic isolation through selection against backcrosses between the three species is strong. Thus, ecological selection in combination with endogenous components and geographic isolation has likely played a significant role in the speciation of P. densata.

  • 1576. Zhou, G Q
    et al.
    Hammarström, Sten
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi, Immunologi/immunkemi.
    Pregnancy-specific glycoprotein (PSG) in baboon (Papio hamadryas): family size, domain structure, and prediction of a functional region in primate PSGs.2001Inngår i: Biology of Reproduction, ISSN 0006-3363, E-ISSN 1529-7268, Vol. 64, nr 1, s. 90-9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pregnancy-specific glycoprotein (PSG) constitutes a major component of serum of pregnant women and appears to be essential for a successful pregnancy. Its function is, however, still unknown. Because of the evolutionary divergence between human and rodent PSG, functional studies may require a primate animal model. We have characterized PSG transcripts in a baboon placenta cDNA library and analyzed baboon genomic DNA. The main PSG isoform had the domain structure N-A1-B2-C similar to the human type IIa isoform. The type I isoform (N-A1-A2-B2-C) was also expressed. Fifteen similar PSG genes were identified of which at least nine were simultaneously expressed in third trimester baboon placenta. Thus, the baboon PSG family was as complex as that of humans. Recombinant baboon PSG (isoform IIa) had a molecular weight of 38 kDa and reacted with antibodies against human PSG. Comparative analysis of 43 N-domain amino acid sequences of PSG from four species and nine primate carcinoembryonic antigen subgroup N domain sequences identified a number of residues in the GFCC'C" ss-sheet and FG loop that are probable candidates for PSG binding to its putative ligand.

  • 1577.
    Zhu, Min
    et al.
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Pan, Zhaohui
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Zhu, Youan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Qiao, Tuo
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Zhao, Wenjin
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Jia, Liantao
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    Lu, Jing
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    A Silurian maxillate placoderm illuminates jaw evolution2016Inngår i: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 354, nr 6310, s. 334-336Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The discovery of Entelognathus revealed the presence of maxilla, premaxilla, and dentary, supposedly diagnostic osteichthyan bones, in a Silurian placoderm. However, the relationship between these marginal jaw bones and the gnathal plates of conventional placoderms, thought to represent the inner dental arcade, remains uncertain. Here we report a second Silurian maxillate placoderm, which bridges the gnathal and maxillate conditions. We propose that the maxilla, premaxilla, and dentary are homologous to the gnathal plates of placoderms and that all belong to the same dental arcade. The gnathal-maxillate transformation occurred concurrently in upper and lower jaws, predating the addition of infradentary bones to the lower jaw.

  • 1578.
    Zhu, Min
    et al.
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Ahlberg, Per E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Zhao, Wen-Jin
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China.;Univ Chinese Acad Sci, Coll Earth Sci, Beijing 100049, Peoples R China..
    Jia, Lian-Tao
    Chinese Acad Sci, Inst Vertebrate Paleontol & Paleoanthropol, Key Lab Vertebrate Evolut & Human Origins, POB 643, Beijing 100044, Peoples R China..
    A Devonian tetrapod-like fish reveals substantial parallelism in stem tetrapod evolution2017Inngår i: Nature Ecology & Evolution, E-ISSN 2397-334X, Vol. 1, nr 10, s. 1470-1476Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The fossils assigned to the tetrapod stem group document the evolution of terrestrial vertebrates from lobe-finned fishes. During the past 18 years the phylogenetic structure of this stem group has remained remarkably stable, even when accommodating new discoveries such as the earliest known stem tetrapod Tungsenia and the elpistostegid (fish-tetrapod intermediate) Tiktaalik. Here we present a large lobe-finned fish from the Late Devonian period of China that disrupts this stability. It combines characteristics of rhizodont fishes (supposedly a basal branch in the stem group, distant from tetrapods) with derived elpistostegid-like and tetrapod-like characters. This melange of characters may reflect either detailed convergence between rhizodonts and elpistostegids plus tetrapods, under a phylogenetic scenario deduced from Bayesian inference analysis, or a previously unrecognized close relationship between these groups, as supported by maximum parsimony analysis. In either case, the overall result reveals a substantial increase in homoplasy in the tetrapod stem group. It also suggest that ecological diversity and biogeographical provinciality in the tetrapod stem group have been underestimated.

  • 1579.
    Zielinski, P.
    et al.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Nadachowska-Brzyska, Krystyna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Dudek, K.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Babik, W.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Divergence history of the Carpathian and smooth newts modelled in space and time2016Inngår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 25, nr 16, s. 3912-3928Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Information about demographic history is essential for the understanding of the processes of divergence and speciation. Patterns of genetic variation within and between closely related species provide insights into the history of their interactions. Here, we investigated historical demography and genetic exchange between the Carpathian (Lissaritan montandoni, Lm) and smooth (L. vulgaris, Lv) newts. We combine an extensive geographical sampling and multilocus nuclear sequence data with the approximate Bayesian computation framework to test alternative scenarios of divergence and reconstruct the temporal and spatial pattern of gene flow between species. A model of recent (last glacial period) interspecific gene flow was favoured over alternative models. Thus, despite the relatively old divergence (4-6 mya) and presumably long periods of isolation, the species have retained the ability to exchange genes. Nevertheless, the low migration rates (ca. 10 per gene copy per generation) are consistent with strong reproductive isolation between the species. Models allowing demographic changes were favoured, suggesting that the effective population sizes of both species at least doubled as divergence reaching the current ca. 0.2 million in Lm and 1 million in Lv. We found asymmetry in rates of interspecific gene flow between Lm and one evolutionary lineage of Lv. We suggest that intraspecific polymorphism for hybrid incompatibilities segregating within Lv could explain this pattern and propose further tests to distinguish between alternative explanations. Our study highlights the importance of incorporating intraspecific genetic structure into the models investigating the history of divergence.

  • 1580.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Karatajute-Talimaa, Valentina
    Vilnius University.
    Aspidin or galeaspidin: new early vertebrate histology from the Lower Silurian of Southern Siberia2011Inngår i: Program and Abstracts: 71st Annual Meeting Society of Vertebrate Paleontology, 2011, s. Sec1: 221-Konferansepaper (Fagfellevurdert)
  • 1581.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Karatajute-Talimaa, Valentina
    Vilnius University.
    Goujet, Daniel
    Museum national d'histoire naturelle.
    Blom, Henning
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Thelodont scales from the Lower and Middle Devonian Andree Land Group, Spitsbergen2013Inngår i: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, nr 1, s. 57-73Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Scales of six thelodont taxa are described from the Devonian of Spitsbergen. Numerous samples from localities widely dispersed on Spitsbergen yield several assemblages considered to represent different depositional phases of the late Lower lower Middle Devonian of the Andrée Land Group, but also support the view that certain lithostratigraphic units of the Andrée Land Group should be regarded as contemporaneous lithofacies subjected to different sedimentary environments, rather than as separate stratigraphic members. The description of Woodfjordia collisa gen. et sp. nov., Talivalia svalbardia sp. nov., Canonia cf. C. grossi, Amaltheolepis montiwatsonia sp. nov., Amaltheolepis winsnesi and Amaltheolepis austfjordia sp. nov. also allows for a comparison with similar faunas from other regions of the Northern Hemisphere and motivates further elaboration of Early-Middle Devonian thelodont biostratigraphy.

  • 1582.
    Zigaite, Zivile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Richter, Martha
    Natural History Museum.
    Karatajute-Talimaa, Valentina
    Vilnius University.
    Meredith Smith, Moya
    King's College London, Dental Institute.
    Tissue diversity and evolutionary trends of the dermal skeleton of Silurian thelodonts2013Inngår i: Historical Biology, ISSN 0891-2963, E-ISSN 1029-2381, Vol. 25, nr 2, s. 143-154Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Previously described scale morphotypes of Silurian thelodonts, constrained by their representation as isolated dermaldenticles are reassessed to provide a more robust character basis for their inclusion in future phylogenetic studies. Asrelatively common microfossils, thelodonts are important biostratigraphical markers, but their interrelationships withgeologically younger species known by complete skeletons are still unresolved. We examined scales of 21 knownmorphotypes from north-eastern Europe, Siberia and central Asia and described their distinct tissue arrangementsconsidering (1) thickness and direction of dentine tubules, (2) presence or absence of a pulp canal, (3) number and positionof pulp canals, (4) the presence or absence of a distinct outer crown layer and (5) the extent of Sharpey’s fibres penetratingthe scale base. We correlated the traditional thelodont scale type morphologies with these distinct scale histologies, as foundin Silurian thelodonts. In addition, a new histological type for thelodont scales, the Talimaalepis type, is described torepresent a new taxon, from the Early-Mid Silurian. Our study suggests that, through time, there is a general trend ofincreasing complexity in thelodont dermal tissue structures. Three types of dentine and internal scale organisations weredistinguished in Silurian species studied, namely (1) irregular, thin tubular dentine; (2) irregular, thick tubular dentine, withtwo subtypes as a function of pulp canal development and (3) regular, tubular dentine (orthodentine).

  • 1583. Zimmermann, Judith
    et al.
    Wentrup, Cecilia
    Sadowski, Miriam
    Blazejak, Anna
    Gruber-Vodicka, Harald R.
    Kleiner, Manuel
    Ott, Jörg A.
    Cronholm, Bodil
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    De Wit, Pierre
    Erseus, Christer
    Dubilier, Nicole
    Closely coupled evolutionary history of ecto- and endosymbionts from two distantly related animal phyla2016Inngår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 25, nr 13, s. 3203-3223Artikkel i tidsskrift (Fagfellevurdert)
  • 1584.
    Zu, Pengjuan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för biologisk grundutbildning.
    Effects of Nectar Production and Pollinator Assemblies on Mating Patterns in Orchids2011Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
    Abstract [en]

    Pollinator visitation patterns should affect pollination success and mating patterns in flowering species. In the orchid family, about one third of the species do not provide any reward for their pollinators. Pollination by deceit is typically associated with low fruit set but may increase the chance of cross-pollination since the pollinator should soon leave the individual plant when there is no reward in the flowers. This may be beneficial if self-fertilisation results in inbreeding depression. I studied the mating patterns of one rewarding and one deceptive orchid in two closely related genera by tracking the fate of stained pollinia. I also conducted controlled crosses to estimate inbreeding depression. The results show that the deceptive orchid Dactylorhiza lapponica has lower pollination success, but higher cross-pollination rate (ca. 90%) than the nectariferous orchid Gymnadenia conopsea (ca. 18% cross-pollination). The results further suggest that in G. conopsea, nocturnal visitors mediate higher geitonogamous pollination rate (ca. 100%) than diurnal visitors (ca. 60%). In both study species, fruits produced from cross-pollination were heavier than fruits produced from selfing. Inbreeding depression for fruit mass did not differ significantly between the two species (δ = 0.21 in D. lapponica and δ = 0.29 in G. conopsea). These data support the hypothesis that pollination by deceit can enhance cross-pollination. A literature study including several rewarding and non-rewarding orchid species indicated lower geitonogamy in the deceptive orchids, but the difference was not statistically significant. 

  • 1585. Zuccolo, Andrea
    et al.
    Scofield, Douglas G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    De Paoli, Emanuele
    Morgante, Michele
    The Ty1-copia LTR retroelement family PARTC is highly conserved in conifers over 200 MY of evolution2015Inngår i: Gene, ISSN 0378-1119, E-ISSN 1879-0038, Vol. 568, nr 1, s. 89-99Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Long Terminal Repeat retroelements (LTR-RTs) are a major component of many plant genomes. Although well studied and described in angiosperms, their features and dynamics are poorly understood in gymnosperms. Representative complete copies of a Ty1-copia element isolate in Picea abies and named PARTC were identified in six other conifer species (Picea glauca, Pinus sylvestris, Pinus taeda, Abies sibirica, Taxus baccata and Juniperus communis) covering more than 200 million years of evolution. Here we characterized the structure of this element, assessed its abundance across conifers, studied the modes and timing of its amplification, and evaluated the degree of conservation of its extant copies at nucleotide level over distant species. We demonstrated that the element is ancient, abundant, widespread and its paralogous copies are present in the genera Picea, Pinus and Abies as an LTR-RT family. The amplification leading to the extant copies of PARTC occurred over long evolutionary times spanning 10 s of MY and mostly took place after the speciation of the conifers analyzed. The level of conservation of PARTC is striking and may be explained by low substitution rates and limited removal mechanisms for LTR-RTs. These PARTC features and dynamics are representative of a more general scenario for LTR-RTs in gymnosperms quite different from that characterizing the vast majority of LTR-RT elements in angiosperms. (C) 2015 Elsevier B.V. All rights reserved.

  • 1586. Zuccon, Dario
    et al.
    Cibois, Alice
    Pasquet, Eric
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Nuclear and mitochondrial sequence data reveal the major lineages of starlings, mynas and related taxa.2006Inngår i: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 41, nr 2, s. 333-44Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigated the phylogenetic relationships among the major lineages of the avian family Sturnidae and their placement within the Muscicapoidea clade using two nuclear (RAG-1 and myoglobin) and one mitochondrial gene (ND2). Among Muscicapoidea, we recovered three clades corresponding to the families Cinclidae, Muscicapidae and Sturnidae (sensu [Sibley, C.G., Monroe Jr., B.L., 1990. Distribution and Taxonomy of Birds of the World. Yale University Press, New Haven, CT]). Within the sturnoid lineage Mimini and Sturnini are sister groups, with Buphagus basal to them. We identified three major lineages of starlings: the Philippine endemic genus Rhabdornis, an Oriental-Australasian clade (genera Scissirostrum, Gracula, Mino, Ampeliceps, Sarcops, Aplonis), and an Afrotropical-Palaearctic clade (all African taxa, Sturnus and Acridotheres). We discuss the biogeographic implications of our findings and suggest an Asiatic origin for this family. The congruence between the age of major clades, estimated by NPRS, and palaeoclimatic data present evidence for the role of climatic changes in shaping present day distribution of the group.

  • 1587.
    Zuccon, Dario
    et al.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    A multi-gene phylogeny disentangles the chat-flycatcher complex (Aves: Muscicapidae)2010Inngår i: Zoologica Scripta, ISSN 0300-3256, E-ISSN 1463-6409, Vol. 39, nr 3, s. 213-224Artikkel i tidsskrift (Fagfellevurdert)
  • 1588. Zuccon, Dario
    et al.
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Molecular and morphological evidences place the extinct New Zealand endemic Turnagra capensis in the Oriolidae.2012Inngår i: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 62, nr 1, s. 414-26Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The affinities of Piopio Turnagra capensis, an extinct New Zealand passerine, remain poorly known. It has been included into or associated with several bird families (Calleatidae, Cracticidae, Pachycephalidae, Ptilonorhynchidae, Turdidae), often on tenuous grounds. We reassessed Turnagra phylogenetic relationships using nuclear and mitochondrial sequences and a set of morphological and behavioural traits. Molecular and phenotypic characters strongly suggest a novel hypothesis, congruently placing Turnagra in Oriolidae, a highly dispersive corvoid family distributed from the Austro-Papuan landmass to Eurasia and Africa, but missing from the Pacific islands. We show also that the published molecular support to link Turnagra with Ptilonorhynchidae was biased by the use of incorrect genetic data and weak analyses.

  • 1589. Zuccon, Dario
    et al.
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    The Monticola rock-thrushes: phylogeny and biogeography revisited.2010Inngår i: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 55, nr 3, s. 901-10Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigated the phylogenetic relationships within the Monticola rock-thrushes, an open-habitat genus inhabiting a large part of the Old World. Our results support one Oriental clade and one clade including African, Malagasy and Eurasian taxa. The biogeographic reconstruction obtained with the dispersal-vicariance analysis suggested Southern Africa plus Palearctic as the Monticola ancestral area. Our phylogenetic hypothesis suggests also some taxonomic changes. The polytypic Monticola solitarius includes two reciprocally monophyletic clades that should be recognized as full species, M. solitarius s.s. and M. philippensis. With the exclusion of the south-western population, M. imerinus, all other Malagasy rock-thrush populations should be merged in the monotypic, albeit polymorphic, M. sharpei. The genus Thamnolaea is shown to be non-monophyletic, with T. semirufa being part of the Monticola radiation, while T. cinnamomeiventris is related to other chat species inhabiting open-habitats. We demonstrate that a previous phylogenetic hypothesis for the rock-thrushes was flawed by the inclusion of contaminated sequences obtained from study-skins and we suggest some working guidelines to improve the reliability of the sequences obtained from old or degraded DNA.

  • 1590.
    Zuccon, Dario
    et al.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    The phylogenetic position of the Black-collared Bulbul Neolestes torquatus2010Inngår i: Ibis, ISSN 0019-1019, E-ISSN 1474-919X, Vol. 152, nr 2, s. 386-392Artikkel i tidsskrift (Fagfellevurdert)
  • 1591.
    Zuccon, Dario
    et al.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Pasquet, Eric
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Phylogenetic relationships among Palearctic-Oriental starlings and mynas (genera Sturnus and Acridotheres: Sturnidae)2008Inngår i: Zoologica Scripta, ISSN 0300-3256, E-ISSN 1463-6409, Vol. 37, nr 5, s. 469-481Artikkel i tidsskrift (Fagfellevurdert)
  • 1592. Zuccon, Dario
    et al.
    Prŷs-Jones, Robert
    Rasmussen, Pamela C
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    The phylogenetic relationships and generic limits of finches (Fringillidae).2012Inngår i: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 62, nr 2, s. 581-96Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Phylogenetic relationships among the true finches (Fringillidae) have been confounded by the recurrence of similar plumage patterns and use of similar feeding niches. Using a dense taxon sampling and a combination of nuclear and mitochondrial sequences we reconstructed a well resolved and strongly supported phylogenetic hypothesis for this family. We identified three well supported, subfamily level clades: the Holoarctic genus Fringilla (subfamly Fringillinae), the Neotropical Euphonia and Chlorophonia (subfamily Euphoniinae), and the more widespread subfamily Carduelinae for the remaining taxa. Although usually separated in a different family-group taxon (Drepanidinae), the Hawaiian honeycreepers are deeply nested within the Carduelinae and sister to a group of Asian Carpodacus. Other new relationships recovered by this analysis include the placement of the extinct Chaunoproctus ferreorostris as sister to some Asian Carpodacus, a clade combining greenfinches (Carduelis chloris and allies), Rhodospiza and Rhynchostruthus, and a well-supported clade with the aberrant Callacanthis and Pyrrhoplectes together with Carpodacus rubescens. Although part of the large Carduelis-Serinus complex, the poorly known Serinus estherae forms a distinct lineage without close relatives. The traditionally delimited genera Carduelis, Serinus, Carpodacus, Pinicola and Euphonia are polyphyletic or paraphyletic. Based on our results we propose a revised generic classification of finches and describe a new monotypic genus for Carpodacus rubescens.

  • 1593.
    Zwoinska, Martyna K.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Lind, Martin I.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Cortazar-Chinarro, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Ramsden, Mark
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Maklakov, Alexei A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Selection on learning performance results in the correlated evolution of sexual dimorphism in life history2016Inngår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, nr 2, s. 342-357Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The evolution of learning can be constrained by trade-offs. As male and female life histories often diverge, the relationship between learning and fitness may differ between the sexes. However, because sexes share much of their genome, intersexual genetic correlations can prevent males and females from reaching their sex-specific optima resulting in intralocus sexual conflict (IaSC). To investigate if IaSC constraints sex-specific evolution of learning, we selected Caenorhabditis remanei nematode females for increased or decreased olfactory learning performance and measured learning, life span (in mated and virgin worms), reproduction, and locomotory activity in both sexes. Males from downward-selected female lines had higher locomotory activity and longer virgin life span but sired fewer progeny than males from upward-selected female lines. In contrast, we found no effect of selection on female reproduction and downward-selected females showed higher locomotory activity but lived shorter as virgins than upward-selected females. Strikingly, selection on learning performance led to the reversal of sexual dimorphism in virgin life span. We thus show sex-specific trade-offs between learning, reproduction, and life span. Our results support the hypothesis that selection on learning performance can shape the evolution of sexually dimorphic life histories via sex-specific genetic correlations.

  • 1594.
    Åberg, Emma
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Anderssson, Eva
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Jemth, Per
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Conservation and divergence in the evolution of binding affinity between p53 and MDM2Manuskript (preprint) (Annet vitenskapelig)
  • 1595.
    Åberg, Emma
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Saccoccia, Fulvio
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Grabherr, Manfred
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Ore, Wai Ying Josefin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Jemth, Per
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi.
    Hultqvist, Greta
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Evolution of the p53-MDM2 pathway2017Inngår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 17, artikkel-id 177Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: The p53 signalling pathway, which controls cell fate, has been extensively studied due to its prominent role in tumor development. The pathway includes the tumor supressor protein p53, its vertebrate paralogs p63 and p73, and their negative regulators MDM2 and MDM4. The p53/p63/p73-MDM system is ancient and can be traced in all extant animal phyla. Despite this, correct phylogenetic trees including both vertebrate and invertebrate species of the p53/p63/p73 and MDM families have not been published. Results: Here, we have examined the evolution of the p53/p63/p73 protein family with particular focus on the p53/ p63/p73 transactivation domain (TAD) and its co-evolution with the p53/p63/p73- binding domain (p53/p63/p73BD) of MDM2. We found that the TAD and p53/p63/p73BD share a strong evolutionary connection. If one of the domains of the protein is lost in a phylum, then it seems very likely to be followed by loss of function by the other domain as well, and due to the loss of function it is likely to eventually disappear. By focusing our phylogenetic analysis to p53/p63/ p73 and MDM proteins from phyla that retain the interaction domains TAD and p53/p63/p73BD, we built phylogenetic trees of p53/p63/p73 and MDM based on both vertebrate and invertebrate species. The trees follow species evolution and contain a total number of 183 and 98 species for p53/p63/p73 and MDM, respectively. We also demonstrate that the p53/p63/p73 and MDM families result from whole genome duplications. Conclusions: The signaling pathway of the TAD and p53/p63/p73BD in p53/p63/p73 and MDM, respectively, dates back to early metazoan time and has since then tightly co-evolved, or disappeared in distinct lineages.

  • 1596.
    Ågren, Jon
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Oakley, Christopher G.
    Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA. WWF Norway, Postboks 6784, N-0130 Oslo, Norway..
    Lundemo, Sverre
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Schemske, Douglas W.
    Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA.;Michigan State Univ, WK Kellogg Biol Stn, E Lansing, MI 48824 USA..
    Adaptive divergence in flowering time among natural populations of Arabidopsis thaliana: Estimates of selection and QTL mapping2017Inngår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, nr 3, s. 550-564Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To identify the ecological and genetic mechanisms of local adaptation requires estimating selection on traits, identifying their genetic basis, and evaluating whether divergence in adaptive traits is due to conditional neutrality or genetic trade-offs. To this end, we conducted field experiments for three years using recombinant inbred lines (RILs) derived from two ecotypes of Arabidopsis thaliana (Italy, Sweden), and at each parental site examined selection on flowering time and mapped quantitative trait loci (QTL). There was strong selection for early flowering in Italy, but weak selection in Sweden. Eleven distinct flowering time QTL were detected, and for each the Italian genotype caused earlier flowering. Twenty-seven candidate genes were identified, two of which (FLC and VIN3) appear under major flowering time QTL in Italy. Seven of eight QTL in Italy with narrow credible intervals colocalized with previously reported fitness QTL, in comparison to three of four in Sweden. The results demonstrate that the magnitude of selection on flowering time differs strikingly between our study populations, that the genetic basis of flowering time variation is multigenic with some QTL of large effect, and suggest that divergence in flowering time between ecotypes is due mainly to conditional neutrality.

  • 1597.
    Ålund, Murielle
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Gametes and speciation: from prezygotic to postzygotic isolation2012Rapport (Annet vitenskapelig)
    Abstract [en]

    Speciation lies at the heart of evolutionary biology and researchers have been trying to understand the mechanisms leading to the evolution of reproductive isolation since over 250 years. Premating barriers (i.e. barriers preventing heterospecific individuals to mate with each other) and extrinsic postzygotic isolation (i.e. environmental factors affecting the fitness of hybrid individuals) have been studied in many taxa. However, little is known about what is happening at the gametic level, both before heterospecific fertilization (i.e. postmating prezygotic or gametic isolation) and in hybrid individuals (i.e. intrinsic postzygotic incompatibilities). In this essay, I will give an overview of the role gametes play in the evolution of reproductive isolation. I conclude that gametes and reproductive proteins evolve quickly, under strong influence of sexual and sexually antagonistic selection. Gametes are very diverse between species and sperm competition and female cryptic choice can lead to higher fertilization success of sperm from conspecific males. In the hybrid offspring, spermatogenesis can be easily disturbed by small differences in gene expression and this leads to a greater number of genes causing hybrid sterility compared to hybrid inviability among taxa. Following Haldane’s rule, the heterogametic sex is the first to be affected by hybrid incompatibilities, but different mechanisms seem to cause inviability and sterility and taxa with heterogametic males or heterogametic females might be affected differently. I end this review by focusing on one particular model system for studying speciation: the Ficedula flycatchers. Much is known about the ecological factors affecting speciation and hybridization between pied and collared flycatchers and new molecular data give insights into the genetics of speciation, but the role of gametes has not been studied in this system. Studies on gamete divergence and hybrid gamete production in the flycatchers will allow us to get a better idea of the role of gametes in speciation in a wild organism with homogametic males.

  • 1598.
    Ålund, Murielle
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Persson-Schmitterlöw, Siri
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    McFarlane, S. Eryn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Qvarnström, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Revisiting the definition of “sperm quality”: selection on sperm length depends on a male’s attractiveness and dominance in wild collared flycatchersManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Dominance over rivals, sexual attractiveness and highly efficient ejaculates are all known to be essential for male fertilization success but the theories of how primary and secondary sexual characters may co-evolve largely remain to be tested. Here, we measure sperm morphology in 131 wild-caught collared flycatchers over a four-year period and investigate the links between male display traits, sperm characteristics and siring success among 425 offspring sired by 71 of these males. We show that the optimal sperm length to attain high relative fertilization success depends on the size of a male’s secondary sexual character. Males with small ornaments sire more offspring in their own nest when they produce long sperm and vice-versa. These results are not compatible with theories based on simple relationships between secondary sexual traits and sperm “quality” but imply that the optimal fertilization strategy (and hence optimal sperm traits) differ between males even in a predominantly socially monogamous population with moderate extra-pair copulation rates. Thus, a better knowledge of the complex chain of behavioural interactions between the sexes and their gametes is needed for a complete understanding of how sexual selection operates in nature.

  • 1599.
    Ålund, Murielle
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Whittington, Emma
    Center for Reproductive Evolution, 248 Life Sciences Complex, Syracuse, NY 13244, USA.
    Backström, Niclas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Borziak, Kirill
    Center for Reproductive Evolution, 248 Life Sciences Complex, Syracuse, NY 13244, USA.
    Jones, Williams
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    McFarlane, S. Eryn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Mugal, Carina F.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Wang, Mi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Wheatcroft, David
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Xu, Luohao
    University of Vienna, Austria.
    Ellegren, Hans
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Immler, Simone
    School of Biological Sciences, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK.
    Dorus, Steve
    Center for Reproductive Evolution, 248 Life Sciences Complex, Syracuse, NY 13244, USA.
    Qvarnström, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Reproductive -omics of a wild avian speciation model unveils candidate genes for gamete interactionManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    The complex nature of interspecific interactions contributing to reproductive isolation means that we still know little about their molecular basis. Male reproductive traits are notorious for their fast evolution at the phenotypic and genotypic level, and divergence in components of the ejaculate can lead to incompatibilities between closely related species. Making use of recent advances of molecular tools and the extensive knowledge on the biology and ecology of young sister species, here the pied (Ficedula hypoleuca) and collared flycatcher (F. albicollis), allows the identification of candidate phenotypes and the underlying genotypes maintaining species boundaries. Pied flycatcher females can avoid costly production of sterile hybrids when mated to collared flycatchers by cryptically favouring conspecific sperm. Here, we describe the testes transcriptome and sperm proteome of both species, confirm the complexity of avian sperm development and functions and identify several candidate genes for interactions between sperm and the female reproductive tract, using multiple independent measures of divergence between the species. We show that divergence at the transcriptional and translational levels can potentially lead to the evolution of reproductive incompatibilities despite low levels of sequence divergence, and suggest that integrating several -omics techniques with knowledge of the biology of naturally hybridizing species will greatly improve our understanding of the molecular basis of speciation in the near future. 

  • 1600.
    Ålund née Podevin, Murielle
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Sex, Sperm and Speciation: On sexual selection and fertility in hybridizing flycatchers2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Sexual reproduction entails complex co-evolution between the sexes, necessary for successful fertilization, ensuring individual and population-level fitness. Interfertility is the main criterion for species definition and understanding speciation requires detailed studies of reproductive barriers. However, many studies on reproductive barriers are constrained to infer evolutionary processes from patterns. In this thesis, I focus on a hybrid zone between collared and pied flycatchers (Ficedula albicollis and hypoleuca) on the island of Öland, and a trait that is essential for fertilization: sperm. Long-term monitoring of these species, combined with recent advances in molecular tools, allow me to study how complex on-going intersexual and interspecific interactions influence reproductive isolation in this young hybrid zone. I start by exploring the links between pre- and postmating sexual selection within collared flycatchers (paper I and II). I show that secondary sexual characters and indirect mate-choice benefits are tightly linked to physiology (paper I), and that a male’s attractiveness and dominance status dictate which sperm traits are optimal, as a male’s fertilization success depends on an interaction between sperm and display traits (paper II). I then report a source of strong postzygotic isolation between recently diverged collared and pied flycatchers: impaired spermatogenesis resulting in absence of mature sperm cells in hybrid males (paper III). I show however that pied flycatcher females, who are most exposed to hybridization, can mitigate these costs through mechanisms of cryptic female choice impairing heterospecific sperm performance, allowing them to bias paternity towards pure-species offspring (paper IV). Finally, by exploring the testes transcriptomes and sperm proteomes of both species, I highlight the importance of gene and protein regulation mechanisms in facilitating phenotypic divergence between these species (paper V). Thus, my thesis reveals complex interactions between primary and secondary sexual characters in a wild bird and suggests that mechanisms of sexual selection are tightly linked to essential physiological functions. I also show that genetic incompatibilities can evolve rapidly despite low genome-wide levels of divergence but that divergence in regulatory regions and proteins potentially allows fast evolution of molecular mechanisms impairing or preventing costly heterospecific fertilization. 

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