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Enumeration	Reference	Cover	Find
1.	Abbott, Jessica, et al. (author) Phenotypic and genetic variation in emergence and development time of a trimorphic damselfly 2005 In: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 18:6, s. 1464-1470 Journal article (peer-reviewed)abstract Although colour polymorphisms in adult organisms of many taxa are often adaptive in the context of sexual selection or predation, genetic correlations between colour and other phenotypic traits expressed early in ontogeny could also play an important role in polymorphic systems. We studied phenotypic and genetic variation in development time among female colour morphs in the polymorphic damselfly Ischnura elegans in the field and by raising larvae in a common laboratory environment. In the field, the three different female morphs emerged at different times. Among laboratory-raised families, we found evidence of a significant correlation between maternal morph and larval development time in both sexes. This suggests that the phenotypic correlation between morph and emergence time in the field has a parallel in a genetic correlation between maternal colour and offspring development time. Maternal colour morph frequencies could thus potentially change as correlated responses to selection on larval emergence dates. The similar genetic correlation in male offspring suggests that sex-limitation in this system is incomplete, which may lead to an ontogenetic sexual conflict between selection for early male emergence (protandry) and emergence times associated with maternal morph.
2.	Andersson, Stefan, et al. (author) Paternal effects on seed germination: a barrier to the genetic assimilation of an endemic plant taxon? 2008 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 21:5, s. 1408-1417 Journal article (peer-reviewed)abstract We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species - the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species' natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener.
3.	Bengtsson, Bengt Olle, et al. (author) The balance between sexual and asexual reproduction in plants living in variable environments 2000 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 13:3, s. 415-422 Journal article (peer-reviewed)abstract The balance between sexual and asexual propagule production is studied in an evolutionary model where plants produce the two kinds of propagules in genetically determined proportions. The male function of plants producing asexual propagules can be varied, and the sexual and asexual propagules carry different probabilities to turn into new reproductive individuals. These fitnesses may vary over years. The evolution of the population’s reproductive system is studied assuming modifier alleles with small effects. In this setting a balanced, mixed reproductive system can evolve, but only if the difference in fitness between the sexual and asexual propagules varies over years. When the two kinds of propagules are very similar to each other, as is often the case with sexual and asexual seed formation, evolution will tend towards a state dominated by the one or the other reproductive system.
4.	Bilde, Trine, et al. (author) Survival benefits select for group living in a social spider despite reproductive costs 2007 In: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 20:6, s. 2412-2426 Journal article (peer-reviewed)abstract The evolution of cooperation requires benefits of group living to exceed costs. Hence, some components of fitness are expected to increase with increasing group size, whereas others may decrease because of competition among group members. The social spiders provide an excellent system to investigate the costs and benefits of group living: they occur in groups of various sizes and individuals are relatively short-lived, therefore life history traits and Lifetime Reproductive Success (LRS) can be estimated as a function of group size. Sociality in spiders has originated repeatedly in phylogenetically distant families and appears to be accompanied by a transition to a system of continuous intra-colony mating and extreme inbreeding. The benefits of group living in such systems should therefore be substantial. We investigated the effect of group size on fitness components of reproduction and survival in the social spider Stegodyphus dumicola in two populations in Namibia. In both populations, the major benefit of group living was improved survival of colonies and late-instar juveniles with increasing colony size. By contrast, female fecundity, female body size and early juvenile survival decreased with increasing group size. Mean individual fitness, estimated as LRS and calculated from five components of reproduction and survival, was maximized for intermediate- to large-sized colonies. Group living in these spiders thus entails a net reproductive cost, presumably because of an increase in intra-colony competition with group size. This cost is traded off against survival benefits at the colony level, which appear to be the major factor favouring group living. In the field, many colonies occur at smaller size than expected from the fitness curve, suggesting ecological or life history constraints on colony persistence which results in a transient population of relatively small colonies.
5.	Calsbeek, B., et al. (author) Multivariate phenotypes and the potential for alternative phenotypic optima in wall lizard (Podarcis muralis) ventral colour morphs 2010 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 23:6, s. 1138-1147 Journal article (peer-reviewed)abstract A major goal in evolutionary biology is to determine how phenotypic variation arises and is maintained in natural populations. Recent studies examining the morphological, physiological and behavioural differences among discrete colour morphotypes (morphs) have revealed several mechanisms that maintain discrete variation within populations, including frequency-dependence, density-dependence and correlational selection. For example, trade-offs over resource allocation to morphological, physiological and behavioural traits can drive correlational selection for morph-specific phenotypic optima. Here, we describe a ventral colour polymorphism in the wall lizard (Podarcis muralis) and test the hypothesis that morphs differ along multivariate axes defined by trade-offs in morphological, physiological, and immunological traits. We show that ventral colour is a discrete trait and that morphs differ in body size, prevalence of infection by parasites and infection intensity. We also find that morphs differ along multivariate phenotypic axes and experience different multivariate selection pressures. Our results suggest that multivariate selection pressures may favour alternative optimal morph-specific phenotypes in P. muralis.
6.	Eroukhmanoff, Fabrice, et al. (author) Phenotypic integration and conserved covariance structure in calopterygid damselflies. 2008 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 21:2, s. 514-526 Journal article (peer-reviewed)abstract By comparing the phenotypic (P) variance-covariance matrices between closely related taxa or conspecific populations, one can study the outcome of the interplay between selection and developmental constraints in phenotypic evolution. Shared patterns of phenotypic integration are also of interest and might result from similarities in either selection or developmental pathways. We compared P-matrices and phenotypic integration indices between populations and species of the damselfly genus Calopteryx. P(max)-comparisons between parapatric C. splendens populations revealed stronger conserved phenotypic covariance structure than P(max)-comparisons between species, suggesting that divergence in its early stages proceeds along phenotypic lines of least resistance. Within- and among-population correlations in C. splendens were highly concordant, in further support of initial divergence along P(max). Despite some similarities in overall phenotypic integration between C. splendens and C. virgo, these two species only had several P-matrix eigenvectors in common, indicating that after reproductive isolation, divergence has proceeded against P(max).
7.	Hargeby, Anders, et al. (author) Is size-assortative mating important for rapid pigment differentiation in a freshwater isopod? 2006 In: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 19:6, s. 1911-1919 Journal article (peer-reviewed)abstract Identifying mechanisms behind assortative mating is central to the understanding of ecological divergence and speciation. Recent studies show that populations of the freshwater isopod Asellus aquaticus can rapidly become locally differentiated when submerged Chara vegetation expands in lakes. In the novel Chara habitat, isopods have become lighter pigmented and smaller than in ancestral reed stands. In this study, we used a laboratory multiple-choice experiment to investigate assortative mating as a possible prezygotic reproductive barrier between Chara and reed isopods. Mating was assortative when Chara isopods were experimentally mixed with isopods from an adjacent reed site with large-size individuals, suggesting a partial prezygotic reproductive barrier. No deviation from random mating could, however, be detected when Chara isopods were mixed with smaller sized isopods from another reed site. In both experiments, assortative mating was apparently based on size, as Chara isopods were larger and reed isopods smaller in mixed pairs than in assortative pairs. Pigmentation did not have any clear influence on mating. We suggest that divergence in pigmentation evolved through natural selection in conjunction with size-assortative mating indirectly causing assortative mating between Chara and reed isopods. Size-assortative mating is likely a by-product of natural selection, but its importance may hypothetically be transient, if selection erodes the correlation between pigmentation and size over time.
8.	Hargeby, Anders, et al. (author) Locally differentiated cryptic pigmentation in the freshwater isopod Asellus aquaticus 2005 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 18:3, s. 713-721 Journal article (peer-reviewed)abstract A repeated pattern of background colour matching in animals is an indication that pigmentation may be cryptic. Here, we examine the relationship between pigmentation of the freshwater isopod Asellus aquaticus and background darkness in 29 lakes, wetlands and ponds in Southern Sweden. The results show that Asellus pigmentation was correlated with substrate darkness across all localities. In seven localities, in which two contrasting substrate types were noted, Asellus populations were differentiated with respect to pigmentation. These findings thus provide phenomenological support for cryptic pigmentation in Asellus. Pigmentation generally increased with body size, but the relationship between pigmentation and size differed among localities, possibly as a result of differences in correlational selection on pigmentation and size. Selection thus appears to have resulted in local differentiation over a small spatial scale, even within lakes and wetlands. This differentiation is a likely cause behind elevated phenotype variation noted in localities with two substrate types, suggesting that habitat heterogeneity promotes genetic diversity.
9.	Jakobsson, Mattias, et al. (author) The evolutionary history of the common chloroplast genome of Arabidopsis thaliana and A. suecica. 2007 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 20:1, s. 104-121 Journal article (peer-reviewed)abstract The evolutionary history of the common chloroplast (cp) genome of the allotetraploid Arabidopsis suecica and its maternal parent A. thaliana was investigated by sequencing 50 fragments of cpDNA, resulting in 98 polymorphic sites. The variation in the A. suecica sample was small, in contrast to that of the A. thaliana sample. The time to the most recent common ancestor (T-MRCA) of the A. suecica cp genome alone was estimated to be about one 37th of the T-MRCA of both the A. thaliana and A. suecica cp genomes. This corresponds to A. suecica having a MRCA between 10 000 and 50 000 years ago, suggesting that the entire species originated during, or before, this period of time, although the estimates are sensitive to assumptions made about population size and mutation rate. The data was also consistent with the hypothesis of A. suecica being of single origin. Isolation-by-distance and population structure in A. thaliana depended upon the geographical scale analysed; isolation-by-distance was found to be weak on the global scale but locally pronounced. Within the genealogical cp tree of A. thaliana, there were indications that the root of the A. suecica species is located among accessions of A. thaliana that come primarily from central Europe. Selective neutrality of the cp genome could not be rejected, despite the fact that it contains several completely linked protein-coding genes.
10.	Karlsson, Kristina, et al. (author) Parallel divergence in mate guarding behaviour following colonization of a novel habitat. 2010 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 23, s. 2540-2549 Journal article (peer-reviewed)abstract Ecological factors can have profound effects on mating system and mating behaviour. We investigated the effect of altered ecological conditions, following colonization of a novel habitat, on precopulatory mate guarding in a freshwater isopod (Asellus aquaticus). This isopod occurs in two different ecotypes, which coexist within several different lakes in Sweden but which utilize different habitats. These ecotypes have rapidly (ca. 40 generations) diverged in parallel among lakes in several phenotypic characters, presumably as a response to different predatory pressures. Here, we demonstrate that also mate guarding characteristics have diverged in parallel between the ecotypes in different lakes. This is one of the few studies reporting parallel evolution of mating behaviour. Furthermore, our results also indicate a potential sexual conflict, as the length of mate guarding appears to lower components of female fitness. We discuss how novel environments might have strong and rapid effects on mate guarding dynamics and mating behaviour.
11.	Lopez-Vaamonde, C, et al. (author) The evolution of host use and unusual reproductive strategies in Achrysocharoides parasitoid wasps 2005 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 18:4, s. 1029-1041 Journal article (peer-reviewed)abstract We studied host selection and exploitation, two crucial aspects of parasite ecology, in Achrysocharoides parasitoid wasps, which show remarkable host specificity and unusual offspring sex allocation. We estimated a molecular phylogeny of 15 Achrysocharoides species and compared this with host (plant and insect) phylogenies. This tri-trophic phylogenetic comparison provides no evidence for cospeciation, but parasitoids do show phylogenetic conservation of the use of plant genera. Patterns of sequence divergence also suggest that the parasitoids radiated more recently (or evolved much faster) than their insect hosts. Three main categories of brood production occur in parasitoids: (1) solitary offspring, (2) mixed sex broods and (3) separate (split) sex broods. Split sex broods are very rare and virtually restricted to Achrysocharoides, while the other types occur very widely. Our phylogeny suggests that split sex broods have evolved twice and provides evidence for a transition from solitary to mixed sex broods, via split sex broods, as predicted by theory.
12.	Lundberg, Max, et al. (author) Characterization of a divergent chromosome region in the willow warbler Phylloscopus trochilus using avian genomic resources. 2011 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 24, s. 1241-1253 Journal article (peer-reviewed)abstract Genome scans have made it possible to find outlier markers thought to have been influenced by divergent selection in almost any wild population. However, the lack of genomic information in nonmodel species often makes it difficult to associate these markers with certain genes or chromosome regions. Furthermore, the extent of linkage disequilibrium (LD) in the genome will determine the density of markers required to identify the genes under selection. In this study, we investigated a chromosome region in the willow warbler Phylloscopus trochilus surrounding a single marker previously identified in a genome scan. We first located the marker in the assembled genome of another species, the zebra finch Taeniopygia guttata, and amplified surrounding sequences in Fennoscandian willow warblers. Within an investigated chromosome region of 7.3 Mb as mapped to the zebra finch genome, we observed elevated genetic differentiation between a southern and a northern population across a 2.5-Mb interval comprising numerous coding genes. Within the southern and northern populations, higher values of LD were mostly found between SNPs within the same locus, but extended across distantly situated loci when the analyses were restricted to sampling sites showing intermediate allele frequencies of southern and northern alleles. Our study shows that cross-species genome information is a useful resource to obtain candidate sequences adjacent to outlier markers in nonmodel species.
13.	Madjidian, Josefin, et al. (author) Influence of number of pollinations and pollen load size on maternal fitness costs in Collinsia heterophylla: implications for existence of a sexual conflict over timing of stigma receptivity. 2012 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 25:8, s. 1623-1635 Journal article (peer-reviewed)abstract Costs related to pollen competition have rarely been considered, but are expected in the case of sexual conflict where male and female sexual functions have opposing evolutionary interests. In Collinsia heterophylla, delayed stigma receptivity is beneficial as it enhances pollen competition. A sexual conflict over timing of stigma receptivity has been proposed in this species as early pollination, following one-time pollinations, is advantageous to pollen donors at a cost of reduced maternal seed set (measured as seed number). In this study, we explored whether the maternal cost was still present following an additional pollination. We hypothesized that the cost is caused either by harm related to early pollen presence or by factors unrelated to harm. We performed pollinations at different stages of floral development, either one or two pollinations (24-h time lag), and varied the size of the first pollen load in the latter category. Early pollination reduced seed biomass also after two-time pollinations, suggesting a persistent maternal cost of early pollen presence. Further, pollen load size modified seed production, possibly indicating that dose-dependent harm influences the maternal cost of early fertilization. Our results strongly suggest negative effects of pollen competition on maternal fitness following early pollination, which is consistent with the existence of a sexual conflict over timing of stigma receptivity. In conclusion, we propose that much could be gained if more plant studies considered the potential for fitness costs in relation to sexual conflict, particularly those investigating pollen-pistil interactions.
14.	Madsen, Thomas, et al. (author) MHC class I variation associates with parasite resistance and longevity in tropical pythons 2006 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 19:6, s. 1973-1978 Journal article (peer-reviewed)abstract Using restriction fragment length polymorphism (RFLP) we identified 26 unique major histocompatibility complex (MHC) genotypes in 104 water pythons. We observed a significant independent association between reduced blood parasite load (Hepatozoon sp.) and python body length/age, presence of a specific RFLP fragment (C-fragment) and the overall number of fragments. The parasite has a negative impact on several python life-history traits such as growth, nutritional status and longevity. Thus, the C-fragment could be considered a 'good gene' (a fitness-enhancing genetic element). However, while the number of fragments affected parasite load, the association between level of parasitaemia and fragment number was not linear, and, hence, minimum parasite infection level was achieved at an intermediate number of fragments. Intermediate MHC fragment numbers were also observed among the largest/oldest pythons, suggesting that both a specific fragment and intermediate levels of MHC polymorphism enhanced python longevity. Thus, our results suggest python MHC is subject to both frequency-dependent and balancing selection.
15.	Marzal, A, et al. (author) Effects of malaria double infection in birds: one plus one is not two. 2008 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 21:4, s. 979-987 Journal article (peer-reviewed)abstract Avian malaria parasites are supposed to exert negative effects on host fitness because these intracellular parasites affect host metabolism. Recent advances in molecular genotyping and microscopy have revealed that coinfections with multiple parasites are frequent in bird-malaria parasite systems. However, studies of the fitness consequences of such double infections are scarce and inconclusive. We tested if the infection with two malaria parasite lineages has more negative effects than single infection using 6 years of data from a natural population of house martins. Survival was negatively affected by both types of infections. We found an additive cost from single to double infection in body condition, but not in reproductive parameters (double-infected had higher reproductive success). These results demonstrate that malaria infections decrease survival, but also have different consequences on the breeding performance of single- and double-infected wild birds.
16.	Natcheva, Rayna, et al. (author) Maternal transmission of cytoplasmic DNA in interspecific hybrids of peat mosses, Sphagnum (Bryophyta). 2007 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 20:4, s. 1613-1616 Journal article (peer-reviewed)abstract The progeny of spontaneous interspecific hybrid sporophytes of Sphagnum were used to analyse the inheritance of cytoplasmic DNA. The analysis showed that only the female parent donated chloroplasts and mitochondria in Sphagnum hybrids. Thus, this is the first study demonstrating maternal cytoplasmic inheritance in a nonvascular land plant. This finding has important implications for phylogenetic reconstructions utilizing chloroplast and mitochondrial DNA sequences as well as for the evolution of cytoplasmic inheritance in relation to the life cycle of land plants.
17.	Prager, Maria, 1973, et al. (author) Phylogeny and evolution of sexually selected tail ornamentation in widowbirds and bishops (Euplectes spp.) 2009 In: J Evol Biol. - : Wiley. ; 22, s. 2068-2076 Journal article (peer-reviewed)abstract Despite similar ecology, mating systems and female preferences for supernormal tails, the 17 species of African widowbirds and bishops (Euplectes spp.) show astonishing variation in male tail ornamentation. Whereas bishops retain their brown nonbreeding tails in nuptial plumage, widowbirds grow black nuptial tails, varying in length from a few centimetres in E. axillaris to the extreme half metre train of E. progne. Here, we phylogenetically reconstruct the evolution of the discrete trait, nuptial tail and the continuous trait, tail length, using a molecular phylogeny of 33 Euplectes subspecies. Unlike many recent findings of labile evolution of plumage ornaments, our results suggest that the nuptial tail of Euplectes is a derived and phylogenetically conserved ornamental trait that, once gained, shows directional evolution in its expression. Directionality is demonstrated in the trivial sense of a short-tailed ancestor, and by contingency and randomization tests suggesting that branches with increasing tail length are overrepresented. This supports an early origin and strong retention of directional female mate choice in widowbirds and bishops, as previously indicated by empirical and experimental results, and provides a less labile, yet rapid scenario of sexually selected diversification.
18.	Richardson, David, et al. (author) Sex-specific associative learning cues and inclusive fitness benefits in the Seychelles warbler 2003 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 16:5, s. 854-861 Journal article (peer-reviewed)abstract In cooperative, breeding vertebrates, indirect fitness benefits would be maximized by subordinates that accurately assess their relatedness to group offspring and preferentially help more closely related kin. In the Seychelles warbler (Acrocephalus sechellensis), we found a positive relationship between subordinate-nestling kinship (determined using microsatellite marker genotypes) and provisioning rates, but only for female subordinates. Female subordinates that helped were significantly more related to the nestlings than were nonhelpers, and the decision to help appears to be based on associative learning cues. High levels of female infidelity means that subordinates cannot trust their legitimacy through the male line, consequently they appear to use the continued presence of the primary female, but not the primary male, as a reliable cue to determine when to feed nestlings. By using effective discrimination, female subordinates are able to maximize the indirect benefits gained within. a cooperative breeding system otherwise driven primarily by direct breeding benefits.
19.	Runemark, Anna, et al. (author) Population divergence in chemical signals and the potential for premating isolation between islet- and mainland populations of the Skyros wall lizard (Podarcis gaigeae). 2011 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 24, s. 795-809 Journal article (peer-reviewed)abstract When sexually selected traits diverge because of different local selective environments, premating isolation might arise as a correlated response. However, sexually selected traits might also diverge by stochastic forces. Here, we show that odour-based mate preferences and scent composition have diverged between islet- and mainland populations of Skyros wall lizard, Podarcis gaigeae. We quantified the degree of scent-mediated premating isolation between populations. Islet lizards preferred scent from islet lizards, whereas the mainland populations were less discriminatory. The pheromone compositions differed more between islets than between islet- and mainland populations and did not differ significantly between mainland populations. There was a tendency for population divergence in pheromones to be positively correlated with neutral genetic divergence. This might indicate a role for genetic drift in evolutionary change in these signals and partial decoupling between signals and preferences. Our results suggest that chemical signals and associated mate preferences can diverge through stochastic and selective forces and influence premating isolation.
20.	Råberg, Lars (author) Infection intensity and infectivity of the tick-borne pathogen Borrelia afzelii. 2012 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 25:7, s. 1448-1453 Journal article (peer-reviewed)abstract The 'trade-off' hypothesis for virulence evolution assumes that between-host transmission rate is a positive and saturating function of pathogen exploitation and virulence, but there are as yet few tests of this assumption, in particular for vector-borne pathogens. Here, I show that the infectivity (probability of transmission) of the tick-borne bacterium Borrelia afzelii from two of its natural rodent hosts (bank vole and yellow-necked mouse) to its main tick vector increases asymptotically with increasing exploitation (measured as bacterial load in skin biopsies). Hence, this result provides support for one of the basic assumptions of the 'trade-off hypothesis'. Moreover, there was no difference in infectivity between bank voles and yellow-necked mice despite bacterial loads being on average an order of magnitude higher in bank voles, most likely because ticks took larger blood meals from mice. This shows that interspecific variation in host resistance does not necessarily translate into a difference in infectivity.
21.	Svensson, Erik, et al. (author) Evolutionary dynamics and population biology of a polymorphic insect 2005 In: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 18:6, s. 1503-1514 Journal article (peer-reviewed)abstract Conspicuous heritable polymorphisms are useful to address the question if morph frequencies are stable or whether they fluctuate between generations. Ecological geneticists have studied colour polymorphisms in the past, but there are few long-term studies of genetic dynamics across multiple generations. We studied morph-frequency dynamics and female fecundity in the trimorphic blue-tailed damselfly (Ischnura elegans). The morphs include a male-coloured (androchrome) type of female, which is thought to be maintained by frequency-dependent sexual conflict. Morph frequencies changed significantly between years across all populations. There was evidence for directional frequency change since androchrome females increased in 9 of 10 populations across a 4-year period. There was heterogeneity between populations in their evolutionary trajectories, partly caused by population age: androchrome frequencies were initially high in young populations but gradually decreased and approached the level of old populations. We discuss the possible causes of morph-frequency fluctuations, and the role of morph-specific fecundity, dispersal and other forces influencing evolutionary dynamics in this system.
22.	Svensson, Erik, et al. (author) Mechanistic and experimental analysis of condition and reproduction in a polymorphic lizard 2002 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 15:6, s. 1034-1047 Journal article (peer-reviewed)abstract The importance of genetic and environmental variation in condition in shaping evolutionary trade-offs have recently been subject to much theoretical discussion, but is very difficult to investigate empirically in most field-based systems. We present the results from mechanistic experimental manipulations of reproductive investment and condition in two female colour morphs (orange and yellow) of side-blotched lizards (Uta stansburiana). We investigated the interactions between throat colour morphs, condition, local social environment and female survival using path-analysis. Using follice-ablation experiments, we show that large clutch size has a negative effect on field survival among yellow females, and that this effect is partly mediated by immunosuppressive effects of large clutches. In orange females these effects were less pronounced, and there was a negative survival effect of strong antibody responses. Hence, we experimentally confirmed our previous findings of correlational selection between female morphotype and immunocompetence, an important condition trait. Manipulation of corticosterone revealed multiple (pleiotropic) direct and indirect effects of this hormone on both condition and reproductive traits. We argue that interaction effects (e.g. between local environments and genotypes) could explain a substantial fraction of variation in condition and reproduction in natural populations. Increased attention to such interaction effects and their fitness consequences will provide novel insights in field studies of selection and reproductive allocation.
23.	Szöllösi, E, et al. (author) Determinants of distribution and prevalence of avian malaria in blue tit populations across Europe: separating host and parasite effects. 2011 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 24, s. 2014-2024 Journal article (peer-reviewed)abstract Although avian malarial parasites are globally distributed, the factors that affect the geographical distribution and local prevalence of different parasite lineages across host populations or species are still poorly understood. Based on the intense screening of avian malarial parasites in nine European blue tit populations, we studied whether distribution ranges as well as local adaptation, host specialization and phylogenetic relationships can determine the observed prevalences within populations. We found that prevalence differed consistently between parasite lineages and host populations, indicating that the transmission success of parasites is lineage specific but is partly shaped by locality-specific effects. We also found that the lineage-specific estimate of prevalence was related to the distribution range of parasites: lineages found in more host populations were generally more prevalent within these populations. Additionally, parasites with high prevalence that were also widely distributed among blue tit populations were also found to infect more host species. These findings suggest that parasites reaching high local prevalence can also realize wide distribution at a global scale that can have further consequences for host specialization. Although phylogenetic relationships among parasites did not predict prevalence, we detected a close match between a tree based on the geographic distance of the host populations and the parasite phylogenetic tree, implying that neighbouring host populations shared a related parasite fauna.
24.	Tschirren, Barbara, et al. (author) Signatures of selection acting on the innate immunity gene Toll-like receptor 2 (TLR2) during the evolutionary history of rodents. 2011 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 24, s. 1232-1240 Journal article (peer-reviewed)abstract Patterns of selection acting on immune defence genes have recently been the focus of considerable interest. Yet, when it comes to vertebrates, studies have mainly focused on the acquired branch of the immune system. Consequently, the direction and strength of selection acting on genes of the vertebrate innate immune defence remain poorly understood. Here, we present a molecular analysis of selection on an important receptor of the innate immune system of vertebrates, the Toll-like receptor 2 (TLR2), across 17 rodent species. Although purifying selection was the prevalent evolutionary force acting on most parts of the rodent TLR2, we found that codons in close proximity to pathogen-binding and TLR2-TLR1 heterodimerization sites have been subject to positive selection. This indicates that parasite-mediated selection is not restricted to acquired immune system genes like the major histocompatibility complex, but also affects innate defence genes. To obtain a comprehensive understanding of evolutionary processes in host-parasite systems, both innate and acquired immunity thus need to be considered.
25.	Waldmann, P, et al. (author) Comparison of genetic (co)variance matrices within and between Scabiosa canescens and S-columbaria 2000 In: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 13:5, s. 826-835 Journal article (peer-reviewed)abstract In the current study, we used bootstrap analyses and the common principal component (CPC) method of Flury (1988) to estimate and compare the G-matrix of Scabiosa columbaria and S. canescens populations. We found three major patterns in the G-matrices: (i) the magnitude of the (co)variances was more variable among characters than among populations, (ii) different populations showed high (co)variance for different characters, and (iii) there was a tendency for S. canescens to have higher genetic (co)variances than S. columbaria. The hypothesis of equal G-matrices was rejected in all comparisons and there was no evidence that the matrices differed by a proportional constant in any of the analyses. The two 'species matrices' were found to be unrelated, both for raw data and data standardized over populations, and there was significant between-population variation in the G-matrix in both species. Populations of S. canescens showed conservation of structure (principal components) in their G-matrices, contrasting with the lack of common structure among the S. columbaria matrices. Given these observations and the results from previous studies, we propose that selection may be responsible for some of the variation between the G-matrices, at least in S. columbaria and at the between-species level.

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