This Review discusses recent advances in the molecular evolution of vertebrate organs, including rates of evolution of organs and cell types, molecular mechanisms of organ evolution and how complex traits contributed to the diversification of vertebrates.

Recent expanded Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) listings for sharks and rays are welcome — yet seizing this opportunity requires that international trade policy is treated not as an end point, but as a catalyst for wider regulatory and market-based reforms.

Baum et al. present a synthesis of field data, remote-sensed data, media reports and process-based modelling analyses examining the effects of the 2021 heatwave in western North America for 32 terrestrial and marine taxa as well as gross primary productivity, streamflow and wildfire activity.

A juvenile iguanodontian from the Lower Cretaceous of China preserves both spikes and scales in its skin that are different from integumentary structures in either non-avian dinosaurs or extant squamates and may have had a defensive function.

Using remote sensing data, spatial modelling and counterfactual scenarios, this analysis reveals a positive relationship between forest patch size and productivity. This implies that preserving many small forest patches may not offset the carbon losses from larger contiguous forests.

Quasi-experimental analysis of the effects of Ethiopia’s protected areas on environmental and human wellbeing is combined with surveys of conservation professionals to explore why improving protected area effectiveness may be prioritized over network expansion.

Analysis of gut bacterial and mitochondrial genomes from wild populations of small rodents across the USA shows that geographic distance mediates early stages of bacterial strain divergence between conspecific mice, while host ancestry impacts microbiota composition across genera.

Whole-genome data from 249 yellow-eyed penguins (hoiho) identify three lineages with high geographical and genomic divergence, and candidate gene variants associated with differential susceptibility to neonatal respiratory distress syndrome.

A compilation of the monetary compensation values assigned to animal species in the legal frameworks of 24 European countries identifies implicit taxonomic and trait influences on these values.

Causal inference should quantify the sensitivity of results to hidden confounders (variables affecting both the location of projects and outcomes). The importance of this is illustrated using analysis of over-crediting in REDD+ projects.

Berin Mackenzie helped to save the last wild trees of their species from extreme fires.

In this Focus issue, we highlight the many and varied effects of extreme events on biodiversity, and how the increasing frequency of these events under climate change is threatening life on land and in water.

As climate change increases the frequency and severity of extreme events, targeted and proactive conservation measures must be implemented to protect endemic tropical island species from the extinction risk posed by cyclones.