The transition from water to land is a question that still intrigues scientists. Those ancient organisms would have needed to ...

Researchers at the University of Bristol have traced the genetic changes that allowed animals to colonize land not once but ...

A newly identified sponge order, Vilesida, produces sterols linked to the oldest-known animal biomarkers, supporting the idea ...

This photograph shows two species from the study by Toussaint et al. – a raccoon (Procyon lotor) and mongoose lemur (Eulemur mongoz) – climbing on vertical supports. Researchers have shed new light on ...

These days, all fish have teeth. The shapes of their teeth vary according to diet, ranging from the little pegs of goldfish ...

Frontmatter -- CONTENTS -- PREFACE AND NOTES -- ACKNOWLEDGMENTS -- 1. Before Animals -- 2. Phylogenetics and the Base of the Animal Tree of Life -- 3. Ctenophora -- 4 ...

The story of two of the strangest animals on the planet just got a little stranger, thanks to clues revealed by a lone fossil specimen that scientists now say represents a long-extinct ancestor. The ...

Sharks might not be a natural biological group, with most species potentially closer kin to rays than to an oddball group of sharks.

If we look across the whole of the mammal branch of the tree of life, we find there are many groups of mammals that have evolved testicles of all different sizes. In almost all these separate cases, ...

A new study argues that human culture — including religion, politics and war — influences how wildlife evolves in cities. In Los Angeles, factors such as policing, zoning, and local values and ...