Explaining the evolution of species geographical ranges is fundamental to understanding
how biodiversity is distributed and maintained. The solution to this classic problem in …

Hybrid zones are 'natural laboratories' for studying the origin, maintenance and demise of
species. Theory predicts that hybrid zones can move in space and time, with significant …

Behaviors can facilitate colonization of a novel environment, but the mechanisms underlying
this process are poorly understood. On one hand, behavioral flexibility allows for an …

Behavioral changes, such as those involved in mating, foraging, and migration, can
generate reproductive barriers between populations. Birds, in particular, are known for their …

In species undergoing range expansion, newly established populations are often more
dispersive than older populations. Because dispersal phenotypes are complex and often …

A review of behavioural studies of hybridization and mixed pairing in birds led to the
following conclusions.(1) Hybridization is more common where one of two hybridizing …

Hybridisation is increasingly recognised as an important cause of diversification and
adaptation. Here, we show how divergence in male secondary sexual characters between …

Abstract Changes in mating signals among populations contribute to species formation.
Often these signals involve a suite of display traits of different sensory modalities …

We analyze variation in phenotypes and mitochondrial DNA (mtDNA) haplotypes over the
breeding ranges of hermit and Townsend's warblers and across two of their three hybrid …

Speciation is one of the most important processes in biology, yet the study of the genomic
changes underlying this process is in its infancy. North American warbler species …