Abstract With the access to draft genome sequence assemblies and whole‐genome resequencing data from population samples, molecular ecology studies will be able take truly genome‐wide approaches. This now applies an avian model system in ecological evolutionary research: Old World flycatchers of genus F icedula , for which we recently obtained a 1.1 Gb collared flycatcher assembly identified 13 million single‐nucleotide polymorphism ( SNP )s this species its sister species, pied flycatcher....

When hybridization is maladaptive, species‐specific mate preferences are selectively favored, but low availability may constrain species‐assortative pairing. Females paired to heterospecifics then benefit by copulating with multiple males and subsequently favoring sperm of conspecifics. Whether such mechanisms for biasing paternity toward conspecifics act as important reproductive barriers in socially monogamous vertebrate species remains be determined. We use a combination long‐term...

Postzygotic isolation may be important for maintaining species boundaries, particularly when premating barriers are incomplete. Little is known about the course of events leading from minor environmental mismatches affecting hybrid fitness to severe genetic incompatibilities causing sterility or inviability. We investigated whether reduced reproductive success males was caused by suboptimal sperm traits more in a zone pied ( Ficedula hypoleuca ) and collared flycatchers F. albicollis on...

Competition-driven evolution of habitat isolation is an important mechanism ecological speciation but empirical support for this process often indirect. We examined how on-going displacement pied flycatchers from their preferred breeding by collared in a young secondary contact zone associated with (a) access to food resource (caterpillar larvae), (b) immigration relation quality, and (c) the risk hybridization quality. Over past 12 years, estimated caterpillar larvae biomass surrounding...

Studies of ecological speciation are often biased towards extrinsic sources selection against hybrids, resulting from intermediate hybrid morphology, but the knowledge how genetic incompatibilities accumulate over time under natural conditions is limited. Here we focus on a physiological trait, metabolic rate, which central to life history strategies and thermoregulation also likely be sensitive mismatched mitonuclear interactions. We measured resting rate male collared, pied flycatchers as...

Divergence in the onset of reproduction can act as an important source reproductive isolation (i.e., allochronic isolation) between co‐occurring young species, but evidence for evolutionary processes leading to such divergence is often indirect. While advancing spring seasons strongly affect many taxa, it remains largely unexplored whether contemporary advancement directly affects species. We examined how increasing temperatures affected and thereby hybridization pied collared flycatchers...

Changes in interacting cis- and trans-regulatory elements are important candidates for Dobzhansky-Muller hybrid incompatibilities may contribute to dysfunction by giving rise misexpression hybrids. To gain insight into the molecular mechanisms determinants of gene expression evolution natural populations, we analyzed transcriptome from multiple tissues two recently diverged Ficedula flycatcher species their naturally occurring F1 Differential analysis revealed that extent differentiation...

Abstract Variation in relative fitness of competing recently formed species across heterogeneous environments promotes coexistence. However, the physiological traits mediating such variation have rarely been identified. Resting metabolic rate ( RMR ) is tightly associated with life history strategies, thermoregulation, diet use, and inhabited latitude could therefore moderate differences responses to fluctuations local environments, particularly when adapted different climates allopatry. We...

AbstractThe frequency and asymmetry of mixed-species mating set the initial stage for ecological evolutionary implications hybridization. How such patterns mating, in turn, are influenced by combination mate choice errors relative species abundance remains largely unknown. We develop a mathematical model that generates predictions how abundances affect hybridization patterns. When small (<5%), highest occurs when one hybridizing is at low abundance, but high (>5%), occur equal proportions....

Abstract Hybrid inviability is an important post-zygotic reproductive barrier between species, but emerging signs of reduced viability can be difficult to study across the lifespan natural hybrids. We use a combination long-term monitoring, extra-pair paternity, and mitochondrial DNA identification in hybrid zone Ficedula flycatchers detect intrinsic their entire lifespan. evaluate possible evidence Darwin’s corollary Haldane’s rule, predicting asymmetries hybrids resulting from reciprocal...

Predicting the impact of climate change on biodiversity requires understanding adaptation potential wild organisms. Evolutionary responses depend additive genetic variation associated with phenotypic traits targeted by selection. We combine 5 years cross-fostering experiments, measurements resting metabolic rate (RMR) nearly 200 collared flycatcher (Ficedula albicollis) nestlings, and animal models using a 17-year pedigree to evaluate for an evolutionary response changing environmental...

Human-induced changes in climate and habitats push populations to adapt novel environments, including new sensory conditions, such as reduced visibility. We studied how colonizing newly formed glacial lakes with turbidity-induced low-visibility affects anti-predator behaviour Icelandic threespine sticklebacks. tested nearly 400 fish from 15 four habitat types varying visibility colonization history their reaction two predator cues (mechano-visual versus olfactory) high light treatments. Fish...

Food availability sets the stage for incubation behaviour of a female bird and thereby indirectly determines nest temperature, which in turn affects development metabolism avian embryos. Changes are known to influence offspring's ability adjust environmental changes later life. However, few studies have investigated role interspecific differences relation niche separation between competing sibling species. We studied effects habitat quality (in terms caterpillar availability) on two...

Fish rely upon vision as a dominant sensory system for foraging, predator avoidance, and mate selection. Damage to the visual system, in particular neural retina of eye, has been demonstrated result regenerative response captive fish that serve model organisms (e.g. zebrafish), this restores some function. The purpose present study is determine whether damage occurs wild populations also results response, offering potentially ecologically relevant retinal regeneration. Adult threespine...

Abstract Species-specific sexual traits facilitate species-assortative mating by reducing across species and hybrid attractiveness. For learned traits, such as song in oscine birds, distinctiveness can be eroded when co-occur. Transcriptional regulatory divergence brain regions involved sensory learning is hypothesized to maintain distinctiveness, but relatively few studies have compared gene expression relevant between closely related species. Species differences are an important premating...

ABSTRACT Evolutionary adaptation occurs when individuals vary in access to fitness‐relevant resources and these differences ‘material wealth’ are heritable. It is typically assumed that the inheritance of material wealth reflects heritable variation phenotypic abilities needed acquire wealth. We scrutinise this assumption by investigating additional mechanisms underlying collared flycatchers. A genome‐wide association analysis reveals a high genomic heritability ( h 2 = 0.405 ± 0.08)...

Dominance over rivals, sexual attractiveness, and highly efficient ejaculates are 3 important contributors of male fertilization success but theories about how primary secondary characters may co-evolve largely remain to be tested. We investigated variation in a signal (forehead patch size) sperm morphology jointly affected siring 70 males natural population collared flycatchers. show that the optimal length attain high relative depended on size male's character. Males with small forehead...