Reviews & Analysis

A cell population in the neural plate border region of embryos of ascidians, the closest relatives of vertebrates, has properties similar to those of the neural crest cells and neuromesodermal cells of vertebrate embryos. The evolutionary origin of these multipotent cells may date back to the common ancestor of vertebrates and ascidians.

Long-term experimental evolution in brewer’s yeast reveals how the transition to simple multicellularity can drive ecological divergence and maintain diversity.

Climate warming is triggering a steady increase in the mean thermal optimum of plant communities. We show that this increase reflects the dieback of cold-adapted species rather than the arrival of warmer-adapted species, with negative effects on local diversity and mutually cancelling effects on community heterogeneity.

We evaluate the drivers of intensification traps — the combined loss of biodiversity and crop production that results from too-intensive agriculture. Our results reveal the conditions under which these lose–lose situations emerge and highlight the strong ramifications of disregarding biodiversity in agricultural management.

Using over 200 chromosomal genomes to reconstruct 250 million years of evolutionary history, we define the 32 linkage groups (Merian elements) that were present in the ancestor of Lepidoptera. We chart the dynamics of chromosome fusion and fission that accompanied the global diversification of Lepidoptera.

Efforts to monitor genetic diversity in populations vary greatly among European countries. The populations and species that are most likely to experience the greatest impacts of climate change are not well covered by these efforts, which suggests an urgent need for a substantial expansion in their monitoring.

Floristic homogenization — an increase in plant similarity within a given region — threatens biodiversity. By studying the taxonomic similarity of the floras of South Pacific islands over the past 5,000 years, we find that initial human settlement was probably a major driver of floristic homogenization.

Sequencing of a hagfish genome — one of the two jawless vertebrate lineages (cyclostomes) — constrains the timing and nature of genome duplication events that characterize early vertebrate evolution. Genome duplications occurred among ancestral vertebrates and cyclostomes, but genome-doubling in ancestral jawed vertebrates was caused by hybridization, which resulted in an unparalleled morphological diversification.

Data that span 15 generations reveal how gene flow and selection in a subordinate mesopredator are affected by pathogen-driven declines in the population density of a top predator. This work highlights the evolutionary impacts of interspecific competition and elucidates landscape-scale effects of an indirect interaction between a pathogen and nonhost species.