While giving birth to live young is a trait that most people associate with mammals, this reproductive mode—also known as viviparity—has evolved over 150 separate times among vertebrates, including ...

Cartilaginous fish have changed much more in the course of their evolutionary history than previously believed. Evidence for this thesis has been provided by new fossils of a ray-like shark, ...

A new study in Genome Biology and Evolution reveals that egg yolk proteins may have been co-opted to provide maternal nutrition in live-bearing sharks and their relatives. While giving birth to live ...