The molecular clock presents a means of estimating evolutionary rates and timescales using
genetic data. These estimates can lead to important insights into evolutionary processes and …

Five decades have passed since the proposal of the molecular clock hypothesis, which
states that the rate of evolution at the molecular level is constant through time and among …

The tree of life is highly reticulate, with the history of population divergence emerging from
populations of gene phylogenies that reflect histories of introgression, lineage sorting and …

Land-use change threatens global biodiversity and may reshape the tree of life by favoring
some lineages over others. Whether phylogenetic diversity loss compromises ecosystem …

Summary Oaks (Quercus, Fagaceae) are the dominant tree genus of North America in
species number and biomass, and Mexico is a global center of oak diversity. Understanding …

Determining the timing of diversification of modern birds has been difficult. We combined
DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate …

Horseshoe crabs (**phosura) are traditionally regarded as sister group to the clade of
terrestrial chelicerates (Arachnida). This hypothesis has been challenged by recent …

A goal of evolutionary biology is to understand the roles of geography and ecology in
speciation. The recent shared ancestry of sister species can leave a major imprint on their …

Changes in chromosome numbers may strongly affect reproductive barriers, because
individuals heterozygous for distinct karyotypes are typically expected to be at least partially …

Background The majority of wood decomposing fungi are mushroom-forming
Agaricomycetes, which exhibit two main modes of plant cell wall decomposition: white rot, in …