The role of historical factors in driving latitudinal diversity gradients is poorly understood.
Here, we used an updated global phylogeny of terrestrial birds to test the role of three key …

High tropical species diversity is often attributed to evolutionary dynamics over long
timescales. It is possible, however, that latitudinal variation in diversification begins when …

Aim Recent research suggests that the latitudinal diversity gradient (LDG) in birds is unlikely
to result from faster diversification in the tropics. This puts the focus on other mechanisms …

Aim The aim of this study was to test a variant of the evolutionary time hypothesis for the bird
latitudinal diversity gradient derived from the effects of niche conservatism in the face of …

Study of the latitudinal diversity gradient to date has focused largely on pattern description,
with relatively little work on the possible mechanisms underlying the pattern. One proximate …

Patterns of evolution are believed to vary latitudinally, but our understanding of this variation
remains limited. Here we examine how patterns of subspecific diversification vary within …

We tested the proposition that there are more species in the tropics because basal clades
adapted to warm paleoclimates have been lost in regions now experiencing cool climates …

Abstract Theory predicts that biogeographic factors should play a central role in promoting
population divergence and speciation. Previous empirical studies into biogeography and …

Aim The global species richness patterns of birds and mammals are strongly congruent. This
could reflect similar evolutionary responses to the Earth's history, shared responses to …

The latitudinal diversity gradient is one of the most striking patterns in nature, yet its
implications for morphological evolution are poorly understood. In particular, it has been …