Random Mating in a Hybrid Zone Between Two Putative Climate-Adapted Bird Lineages With Predicted Mitonuclear Incompatibilities.

Biochemical and evolutionary interactions between mitochondrial and nuclear genomes ('mitonuclear interactions') are proposed to underpin fundamental aspects of biology including evolution of sexual reproduction, adaptation and speciation. We investigated the role of pre-mating isolation in maintaining functional mitonuclear interactions in wild populations bearing diverged, putatively co-adapted mitonuclear genotypes. Two lineages of eastern yellow robin Eopsaltria australis-putatively climate-adapted to 'inland' and 'coastal' climates-differ by ~7% of mitogenome nucleotides, whereas nuclear genome differences are concentrated into a sex-linked region enriched with mitochondrial functions.

Accelerated differentiation of neo-W nuclear-encoded mitochondrial genes between two climate-associated bird lineages signals potential co-evolution with mitogenomes.

There is considerable evidence for mitochondrial-nuclear co-adaptation as a key evolutionary driver. Hypotheses regarding the roles of sex-linkage have emphasized Z-linked nuclear genes with mitochondrial function (N-mt genes), whereas it remains contentious whether the perfect co-inheritance of W genes with mitogenomes could hinder or facilitate co-adaptation. Young (neo-) sex chromosomes that possess relatively many N-mt genes compared to older chromosomes provide unprecedented hypothesis-testing opportunities.

Easy-to-use R functions to separate reduced-representation genomic datasets into sex-linked and autosomal loci, and conduct sex assignment.

Identifying sex-linked markers in genomic datasets is important because their presence in supposedly neutral autosomal datasets can result in incorrect estimates of genetic diversity, population structure and parentage. However, detecting sex-linked loci can be challenging, and available scripts neglect some categories of sex-linked variation. Here, we present new R functions to (1) identify and separate sex-linked loci in ZW and XY sex determination systems and (2) infer the genetic sex of individuals based on these loci.

Concordant divergence of mitogenomes and a mitonuclear gene cluster in bird lineages inhabiting different climates.

Metabolic processes in eukaryotic cells depend on interactions between mitochondrial and nuclear gene products (mitonuclear interactions). These interactions could have a direct role in population divergence. Here, we study mitonuclear co-evolution in a widespread bird that experienced population divergence followed by bidirectional mitochondrial introgression into different nuclear backgrounds.

Species- and sex-specific connectivity effects of habitat fragmentation in a suite of woodland birds.

Loss of functional connectivity following habitat loss and fragmentation could drive species declines. A comprehensive understanding of fragmentation effects on functional connectivity of an ecological assemblage requires investigation of multiple species with different mobilities, at different spatial scales, for each sex, and in different landscapes. Based on published data on mobility and ecological responses to fragmentation of 10 woodland-dependent birds, and using simulation studies, we predicted that (1) fragmentation would impede dispersal and gene flow of eight "decliners" (species that disappear from suitable patches when landscape-level tree cover falls below species-specific thresholds), but not of two "tolerant" species (whose occurrence in suitable habitat patches is independent of landscape tree cover); and that fragmentation effects would be stronger (2) in the least mobile species, (3) in the more philopatric sex, and (4) in the more fragmented region.

Perched at the mito-nuclear crossroads: divergent mitochondrial lineages correlate with environment in the face of ongoing nuclear gene flow in an Australian bird.

Relationships among multilocus genetic variation, geography, and environment can reveal how evolutionary processes affect genomes. We examined the evolution of an Australian bird, the eastern yellow robin Eopsaltria australis, using mitochondrial (mtDNA) and nuclear (nDNA) genetic markers, and bioclimatic variables. In southeastern Australia, two divergent mtDNA lineages occur east and west of the Great Dividing Range, perpendicular to latitudinal nDNA structure.

Does reduced mobility through fragmented landscapes explain patch extinction patterns for three honeyeaters?

Habitat loss and associated fragmentation are major drivers of biodiversity decline, and understanding how they affect population processes (e.g. dispersal) is an important conservation goal.

Disrupted fine-scale population processes in fragmented landscapes despite large-scale genetic connectivity for a widespread and common cooperative breeder: the superb fairy-wren (Malurus cyaneus).

Understanding how habitat fragmentation affects population processes (e.g. dispersal) at different spatial scales is of critical importance to conservation.

Genes and song: genetic and social connections in fragmented habitat in a woodland bird with limited dispersal.

Understanding the processes leading to population declines in fragmented landscapes is essential for successful conservation management. However, isolating the influence of disparate processes, and dispersal in particular, is challenging. The Grey Shrike-thrush, Colluricincla harmonica, is a sedentary woodland-dependent songbird, with learned vocalizations whose incidence in suitable habitat patches falls disproportionally with decline in tree cover in the landscape.

Predicting landscape-genetic consequences of habitat loss, fragmentation and mobility for multiple species of woodland birds.

Inference concerning the impact of habitat fragmentation on dispersal and gene flow is a key theme in landscape genetics. Recently, the ability of established approaches to identify reliably the differential effects of landscape structure (e.g.