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Contrasting patterns of nucleotide polymorphism suggest different selective regimes within different parts of the PgiC1 gene in Festuca ovina L.

Swedish Research Council. Bengt Hansson also acknowledges support from the Swedish Research Council (grant 621-2014-5222). The funders had no role in study design, data collection and analysis, decision to

Transcriptome profiling in the damselfly Ischnura elegans identifies genes with sex-biased expression

Background Sexual dimorphism occurs widely across the animal kingdom and has profound effects on evolutionary trajectories. Here, we investigate sex-specific gene expression in Ischnura elegans (Odonata: dragonflies and damselflies), a species with pronounced sexual differences including a female-limited colour polymorphism with two female-like gynochrome morphs and one ...

Population structure and genetic diversity in the nannandrous moss Homalothecium lutescens: does the dwarf male system facilitate gene flow?

Background Nannandry is a sexual system where males (”dwarf males”) are much smaller than the conspecific females. Dwarf males occur in a wide range of unrelated organisms but the evolutionary advantages of this condition are poorly understood. The dwarf male sexual system results in differences in the mode of dispersal and establishment as well as the life span between males and ...

Odonata (dragonflies and damselflies) as a bridge between ecology and evolutionary genomics

Odonata (dragonflies and damselflies) present an unparalleled insect model to integrate evolutionary genomics with ecology for the study of insect evolution. Key features of Odonata include their ancient phylogenetic position, extensive phenotypic and ecological diversity, several unique evolutionary innovations, ease of study in the wild and usefulness as bioindicators for ...

Pronounced Fixation, Strong Population Differentiation and Complex Population History in the Canary Islands Blue Tit Subspecies Complex

Evolutionary molecular studies of island radiations may lead to insights in the role of vicariance, founder events, population size and drift in the processes of population differentiation. We evaluate the degree of population genetic differentiation and fixation of the Canary Islands blue tit subspecies complex using microsatellite markers and aim to get insights in the population ...

Individual Identification and Genetic Variation of Lions (Panthera leo) from Two Protected Areas in Nigeria

This survey was conducted in two protected areas in Nigeria to genetically identify individual lions and to determine the genetic variation within and between the populations. We used faecal sample DNA, a non-invasive alternative to the risky and laborious task of taking samples directly from the animals, often preceded by catching and immobilization. Data collection in Yankari ...

De novo transcriptome of Ischnura elegans provides insights into sensory biology, colour and vision genes

Background There is growing interest in odonates (damselflies and dragonflies) as model organisms in ecology and evolutionary biology but the development of genomic resources has been slow. So far only one draft genome (Ladona fulva) and one transcriptome assembly (Enallagma hageni) have been published. Odonates have some of the most advanced visual systems among insects and ...

Patterns of Molecular Evolution of an Avian Neo-sex Chromosome

Newer parts of sex chromosomes, neo-sex chromosomes, offer unique possibilities for studying gene degeneration and sequence evolution in response to loss of recombination and population size decrease. We have recently described a neo-sex chromosome system in Sylvioidea passerines that has resulted from a fusion between the first half (10 Mb) of chromosome 4a and the ancestral sex ...

Sex-Biased Gene Expression on the Avian Z Chromosome: Highly Expressed Genes Show Higher Male-Biased Expression

Dosage compensation, the process whereby expression of sex-linked genes remains similar between sexes (despite heterogamety) and balanced with autosomal expression, was long believed to be essential. However, recent research has shown that several lineages, including birds, butterflies, monotremes and sticklebacks, lack chromosome-wide dosage compensation mechanisms and do not ...

Ancestral polymorphism at the major histocompatibility complex (MHCIIβ) in the Nesospiza bunting species complex and its sister species (Rowettia goughensis)

. This work received financial support from a European Union IRSES grant (PIRSES-GA-2008-230799) and South Africa/ Sweden Bilateral funding (348-2008-6131) to Paulette Bloomer, Bengt Hansson, and Peter ... Ryan; and research grants from the Crafoord Foundation and the Swedish Research Council to Bengt Hansson. 1. Dlugosch KM : Parker: Founding events in species invasions: genetic variation, adaptive

Hybridization but No Evidence for Backcrossing and Introgression in a Sympatric Population of Great Reed Warblers and Clamorous Reed Warblers

Hybridization is observed frequently in birds, but often it is not known whether the hybrids are fertile and if backcrossing occurs. The breeding ranges of the great reed warbler (Acrocephalus arundinaceus) and the clamorous reed warbler (A. stentoreus) overlap in southern Kazakhstan and a previous study has documented hybridization in a sympatric population. In the present study, ...

Annual Cycle and Migration Strategies of a Trans-Saharan Migratory Songbird: A Geolocator Study in the Great Reed Warbler

. Competing interests: It is correct that co-author Bengt Hansson is a PLOS ONE Editorial Board member. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials

Ontogenetic shifts in male mating preference and morph-specific polyandry in a female colour polymorphic insect

Background Sexual conflict over mating rates may favour the origin and maintenance of phenotypes with contrasting reproductive strategies. The damselfly Ischnura elegans is characterised by a female colour polymorphism that consists of one androchrome and two gynochrome female morphs. Previous studies have shown that the polymorphism is genetic and to a high extent maintained by ...

Assessing Multivariate Constraints to Evolution across Ten Long-Term Avian Studies

Background In a rapidly changing world, it is of fundamental importance to understand processes constraining or facilitating adaptation through microevolution. As different traits of an organism covary, genetic correlations are expected to affect evolutionary trajectories. However, only limited empirical data are available. Methodology/Principal Findings We investigate the extent ...

Introgression and rapid species turnover in sympatric damselflies

Background Studying contemporary hybridization increases our understanding of introgression, adaptation and, ultimately, speciation. The sister species Ischnura elegans and I. graellsii (Odonata: Coenagrionidae) are ecologically, morphologically and genetically similar and hybridize. Recently, I. elegans has colonized northern Spain, creating a broad sympatric region with I. ...

Environmental and Climatic Determinants of Molecular Diversity and Genetic Population Structure in a Coenagrionid Damselfly

Identifying environmental factors that structure intraspecific genetic diversity is of interest for both habitat preservation and biodiversity conservation. Recent advances in statistical and geographical genetics make it possible to investigate how environmental factors affect geographic organisation and population structure of molecular genetic diversity within species. Here we ...

The sex-biased brain: sexual dimorphism in gene expression in two species of songbirds

Background Despite virtually identical DNA sequences between the sexes, sexual dimorphism is a widespread phenomenon in nature. To a large extent the systematic differences between the sexes must therefore arise from processes involving gene regulation. In accordance, sexual dimorphism in gene expression is common and extensive. Genes with sexually dimorphic regulation are known to ...

Island biology and morphological divergence of the Skyros wall lizard Podarcis gaigeae: a combined role for local selection and genetic drift on color morph frequency divergence?

divergence? Anna Runemark 0 Bengt Hansson 0 Panayiotis Pafilis Efstratios D Valakos Erik I Svensson 0 0 Section for Animal Ecology , Ecology Building , Lund University , SE-223 62 Lund , Sweden Background

A strong quantitative trait locus for wing length on chromosome 2 in a wild population of great reed warblers

Wing length is a key character for essential behaviours related to bird flight such as migration and foraging. In the present study, we initiate the search for the genes underlying wing length in birds by studying a long-distance migrant, the great reed warbler (Acrocephalus arundinaceus). In this species wing length is an evolutionary interesting trait with pronounced latitudinal ...

Postglacial Colonisation Patterns and the Role of Isolation and Expansion in Driving Diversification in a Passerine Bird

Pleistocene glacial cycles play a major role in diversification and speciation, although the relative importance of isolation and expansion in driving diversification remains debated. We analysed mitochondrial DNA sequence data from 15 great reed warbler (Acrocephalus arundinaceus) populations distributed over the vast Eurasian breeding range of the species, and revealed unexpected ...