Sexual transmission may drive pair similarity of the cloacal microbiome in a polyandrous species.

All animals host a microbial community within and on their reproductive organs, known as the reproductive microbiome. In free-living birds, studies on the sexual transmission of bacteria have typically focused on a few pathogens instead of the bacterial community as a whole, despite a potential link to reproductive function. Theory predicts higher sexual transmission of the reproductive microbiome in females via the males' ejaculates and higher rates of transmission in promiscuous systems.

Morph-dependent fitness and directional change of morph frequencies over time in a Dutch population of Common buzzards Buteo buteo.

How genetic polymorphisms are maintained in a population is a key question in evolutionary ecology. Previous work on a plumage colour polymorphism in the common buzzard Buteo buteo suggested heterozygote advantage as the mechanism maintaining the co-existence of three morphs (light, intermediate and dark). We took advantage of 20 years of life-history data collected in a Dutch population to replicate earlier studies on the relationship between colour morph and fitness in this species.

Variation in fine-scale genetic structure and local dispersal patterns between peripheral populations of a South American passerine bird.

The distribution of suitable habitat influences natal and breeding dispersal at small spatial scales, resulting in strong microgeographic genetic structure. Although environmental variation can promote interpopulation differences in dispersal behavior and local spatial patterns, the effects of distinct ecological conditions on within-species variation in dispersal strategies and in fine-scale genetic structure remain poorly understood. We studied local dispersal and fine-scale genetic structure in the thorn-tailed rayadito (), a South American bird that breeds along a wide latitudinal gradient.

Sources of (co)variation in alternative siring routes available to male great tits (Parus major).

Males of socially monogamous species can increase their siring success via within-pair and extra-pair fertilizations. In this study, we focused on the different sources of (co)variation between these siring routes, and asked how each contributes to total siring success. We quantified the fertilization routes to siring success, as well as behaviors that have been hypothesized to affect siring success, over a five-year period for a wild population of great tits Parus major.

Adaptive sleep loss in polygynous pectoral sandpipers.

The functions of sleep remain elusive. Extensive evidence suggests that sleep performs restorative processes that sustain waking brain performance. An alternative view proposes that sleep simply enforces adaptive inactivity to conserve energy when activity is unproductive.

Isolation and characterization of polymorphic microsatellite loci for the northern flicker (Colaptes auratus; Aves).

To investigate the mating system of northern flickers (Colaptes auratus), we developed primers for 14 microsatellite loci and screened them in 68 unrelated adults and their offspring. All markers were highly polymorphic with 9 to +36 alleles per locus. One marker was Z-chromosome linked; one marker exceeded the size standard range and could not be analysed further.

Drd4 gene polymorphisms are associated with personality variation in a passerine bird.

Polymorphisms in several neurotransmitter-associated genes have been associated with variation in human personality traits. Among the more promising of such associations is that between the human dopamine receptor D4 gene (Drd4) variants and novelty-seeking behaviour. However, genetic epistasis, genotype-environment interactions and confounding environmental factors all act to obscure genotype-personality relationships.

Convergent evolution of strigiform and caprimulgiform dark-activity is supported by phylogenetic analysis using the arylalkylamine N-acetyltransferase (Aanat) gene.

Alternative hypotheses propose the sister order of owls (Strigiformes) to be either day-active raptors (Falconiformes) or dark-active nightjars and allies (Caprimulgiformes). In an effort to identify molecular characters distinguishing between these hypotheses we examined a gene, arylalkylamine N-acetyltransferase (Aanat), potentially associated with the evolution of avian dark-activity. Partial Aanat coding sequences, and two introns, were obtained from the genomic DNA of 16 species: Strigiformes (four species), Falconiformes (four species), Caprimulgiformes (five species), with outgroups: Ciconiiformes (one species), Passeriformes (one species), and Apterygiformes (one species).