Inheritance of Material Wealth in a Natural Population.

Evolutionary adaptation occurs when individuals vary in access to fitness-relevant resources and these differences in 'material wealth' are heritable. It is typically assumed that the inheritance of material wealth reflects heritable variation in the phenotypic abilities needed to acquire material wealth. We scrutinise this assumption by investigating additional mechanisms underlying the inheritance of material wealth in collared flycatchers.

Divergence in expression of a singing-related neuro-plasticity gene in the brains of two Ficedula flycatchers and their hybrids.

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

Synthesis and Scope of the Role of Postmating Prezygotic Isolation in Speciation.

How barriers to gene flow arise and are maintained are key questions in evolutionary biology. Speciation research has mainly focused on barriers that occur either before mating or after zygote formation. In comparison, postmating prezygotic (PMPZ) isolation-a barrier that acts after gamete release but before zygote formation-is less frequently investigated but may hold a unique role in generating biodiversity.

Tracking hybrid viability across life stages in a natural avian contact zone.

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 of natural hybrids. We use a combination of long-term monitoring, extra-pair paternity, and mitochondrial DNA identification in a natural hybrid zone of Ficedula flycatchers to detect emerging signs of intrinsic hybrid inviability across their entire lifespan. We evaluate possible evidence of Darwin's corollary to Haldane's rule, predicting asymmetries in inviability between hybrids resulting from reciprocal crosses, due to incompatible genetic factors with sex-specific inheritance patterns.

Anthropogenic Change and the Process of Speciation.

Anthropogenic impacts on the environment alter speciation processes by affecting both geographical contexts and selection patterns on a worldwide scale. Here we review evidence of these effects. We find that human activities often generate spatial isolation between populations and thereby promote genetic divergence but also frequently cause sudden secondary contact and hybridization between diverging lineages.

Assortative Mating in an Ecological Context: Effects of Mate Choice Errors and Relative Species Abundance on the Frequency and Asymmetry of Hybridization.

AbstractThe frequency and asymmetry of mixed-species mating set the initial stage for the ecological and evolutionary implications of hybridization. How such patterns of mixed-species mating, in turn, are influenced by the combination of mate choice errors and relative species abundance remains largely unknown. We develop a mathematical model that generates predictions for how relative species abundances and mate choice errors affect hybridization patterns.

Eye flukes (Diplostomum spp) damage retinal tissue and may cause a regenerative response in wild threespine stickleback fish.

Fish rely upon vision as a dominant sensory system for foraging, predator avoidance, and mate selection. Damage to the visual system, in particular to the neural retina of the eye, has been demonstrated to result in a regenerative response in captive fish that serve as model organisms (e.g.

Sensory environment affects Icelandic threespine stickleback's anti-predator escape behaviour.

Human-induced changes in climate and habitats push populations to adapt to 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 in Icelandic threespine sticklebacks. We tested nearly 400 fish from 15 populations and four habitat types varying in visibility and colonization history in their reaction to two predator cues (mechano-visual versus olfactory) in high versus low-visibility light treatments.

Low Heritability but Significant Early Environmental Effects on Resting Metabolic Rate in a Wild Passerine.

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

Tissue-specific patterns of regulatory changes underlying gene expression differences among flycatchers and their naturally occurring F hybrids.

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

Differences in incubation behaviour and niche separation of two competing flycatcher species.

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

Academic ecosystems must evolve to support a sustainable postdoc workforce.

The postdoctoral workforce comprises a growing proportion of the science, technology, engineering and mathematics (STEM) community, and plays a vital role in advancing science. Postdoc professional development, however, remains rooted in outdated realities. We propose enhancements to postdoc-centred policies and practices to better align this career stage with contemporary job markets and work life.

Difference in plasticity of resting metabolic rate - the proximate explanation to different niche breadth in sympatric flycatchers.

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

Climate-driven build-up of temporal isolation within a recently formed avian hybrid zone.

Divergence in the onset of reproduction can act as an important source of reproductive isolation (i.e., allochronic isolation) between co-occurring young species, but evidence for the evolutionary processes leading to such divergence is often indirect.

Correction: Hybrid Dysfunction Expressed as Elevated Metabolic Rate in Male Ficedula Flycatchers.

[This corrects the article DOI: 10.1371/journal.pone.

Hybrid Dysfunction Expressed as Elevated Metabolic Rate in Male Ficedula Flycatchers.

Studies of ecological speciation are often biased towards extrinsic sources of selection against hybrids, resulting from intermediate hybrid morphology, but the knowledge of how genetic incompatibilities accumulate over time under natural conditions is limited. Here we focus on a physiological trait, metabolic rate, which is central to life history strategies and thermoregulation but is also likely to be sensitive to mismatched mitonuclear interactions. We measured the resting metabolic rate of male collared, and pied flycatchers as well as of naturally occurring F1 hybrid males, in a recent hybrid zone.

Competition-driven build-up of habitat isolation and selection favoring modified dispersal patterns in a young avian hybrid zone.

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

Females discriminate against heterospecific sperm in a natural hybrid zone.

When hybridization is maladaptive, species-specific mate preferences are selectively favored, but low mate availability may constrain species-assortative pairing. Females paired to heterospecifics may 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 to be determined.

Climate adaptation and speciation: particular focus on reproductive barriers in Ficedula flycatchers.

Climate adaptation is surprisingly rarely reported as a cause for the build-up of reproductive isolation between diverging populations. In this review, we summarize evidence for effects of climate adaptation on pre- and postzygotic isolation between emerging species with a particular focus on pied (Ficedula hypoleuca) and collared (Ficedula albicollis) flycatchers as a model for research on speciation. Effects of climate adaptation on prezygotic isolation or extrinsic selection against hybrids have been documented in several taxa, but the combined action of climate adaptation and sexual selection is particularly well explored in Ficedula flycatchers.

Offloading treatment is linked to activation of proinflammatory cytokines and start of bone repair and remodeling in Charcot arthropathy patients.

Background: Proinflammatory cytokines are an integral part of the osteolytic activity of Charcot arthropathy but are also central to normal bone healing. As there are no previous longitudinal studies investigating their role during the recovery phase of Charcot, we set out to monitor systemic levels of proinflammatory cytokines from Charcot presentation until a clinically and radiographically documented chronic state has been reached.

Methods: Twenty-eight consecutive Charcot patients were monitored during 2 years by repeated foot radiographs, MRI and plasma levels of interleukin [IL]-6, IL-8, IL-1β, Tumor Necrosis Factor [TNF]-α, and IL-1 receptor antibody (IL-1RA).

IL-17 cytokines in bone healing of diabetic Charcot arthropathy patients: a prospective 2 year follow-up study.

Background: Little is currently known of the pathophysiological mechanisms triggering Charcot arthropathy and regulating its recovery although foot trauma has been proposed as a major initiating factor by activation of proinflammatory cytokines leading to increased osteoclastogenic activity and progressive bone destruction. Several members of the IL-17 family of proinflammatory cytokines have been shown to play a key role in the pathogenesis of inflammatory conditions affecting bone and joints but none has previously been studied in Charcot foot patients. The aim of this study was to investigate the role of IL-17A, IL-17E and IL-17F in patients presenting with Charcot foot.

Role of Wnt/β-catenin and RANKL/OPG in bone healing of diabetic Charcot arthropathy patients.

Background And Purpose: Charcot neuropathy is characterized by bone destruction in a foot leading to deformity, instability, and risk of amputation. Little is known about the pathogenic mechanisms. We hypothesized that the bone-regulating Wnt/β-catenin and RANKL/OPG pathways have a role in Charcot arthropathy.

Estimation of linkage disequilibrium and interspecific gene flow in Ficedula flycatchers by a newly developed 50k single-nucleotide polymorphism array.

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