Deserts are often misperceived as desolate, non-productive landscapes. This perception contributes to the misuse of terms like ‘semiarid’ and ‘desertification’, creating ambiguity in how deserts are defined and geographically delineated. Such conceptual confusion can hinder effective policy by obscuring what constitutes a desert and where they occur. We identify key incongruencies between climatic and ecological approaches to...

Climate and land use changes pose the greatest threats to biodiversity, but their synergistic effects on biodiversity have been rarely studied. Here, we assessed the combined effects of future climate and land use changes on the world's land vertebrates (29,657 species) across four socioeconomic scenarios between 2015 and 2100. We evaluated species range exposures to extreme heat events (relative to temperatures during 1950–20...

Aim Sexual size dimorphism (SSD) is widespread in the animal kingdom. The direction and magnitude of SSD differ considerably across taxa, potentially due to different selective forces acting on female and male sizes. We assembled a comprehensive database of mean body sizes for female and male squamate species. We then tested for associations between the degree and direction of sexual size dimorphism and environmental factors,...

Aim Squamate fitness is affected by body temperature, which in turn is influenced by environmental temperatures and, in many species, by exposure to solar radiation. The biophysical drivers of body temperature have been widely studied, but we lack an integrative synthesis of actual body temperatures experienced in the field, and their relationships to environmental temperatures, across phylogeny, behaviour and climate. Locatio...

Aim Viviparity has evolved more times in squamates than in any other vertebrate group; therefore, squamates offer an excellent model system in which to study the patterns, drivers and implications of reproductive mode evolution. Based on current species distributions, we examined three selective forces hypothesized to drive the evolution of squamate viviparity (cold climate, variable climate and hypoxic conditions) and tested...