The extent to which the sequence and timing of important events on Earth have influenced
biological evolution through geological time is a matter of ongoing debate. In this context …

Classification of the tremendous diversity of ray-finned fishes (Actinopterygii) began with the
designation of taxonomic groups on the basis of morphological similarity. Starting in the late …

Major ecological transitions are thought to fuel diversification, but whether they are
contingent on the evolution of certain traits called key innovations 1 is unclear. Key …

Rising temperatures, drought, and oxygen depletion may be the greatest threats to aquatic
animals in the twenty-first century. As a robust body of literature suggests, large-bodied fish …

Colonization of a novel habitat is often followed by phenotypic diversification in the wake of
ecological opportunity. However, some habitats should be inherently more constraining than …

The functional traits of species depend both on species' evolutionary characteristics and
their local environmental conditions and opportunities. The temperature-size rule (TSR), gill …

Eurypterids—Palaeozoic marine and freshwater arthropods commonly known as sea
scorpions—repeatedly evolved to remarkable sizes (over 0.5 m in length) and colonized …

Pinnipeds (seals, sea lions, walruses, and their fossil relatives) are one of the most
successful mammalian clades to live in the oceans. Despite a well-resolved molecular …

Aim Global interspecific body size distributions have been suggested to be shaped by
selection pressures arising from biotic and abiotic factors such as temperature, predation …

Organismal morphology has been at the core of study of biodiversity for millennia before the
formalization of the concept of evolution. In the early to mid-twentieth century, a strong …