For millions of years, some of Earth’s earliest animals barely changed. They lived, grew, and spread across the seafloor, but ...

A study has found that the reason why the evolution of the first animals to appear on Earth was delayed for over 10 million ...

Our planet is filled with a dazzling variety of creatures that bump uglies to reproduce. Cats do it. Dogs do it. The birds and the bees definitely do it. But what were the first animals to have sex?

Some animals can have babies without the need to mate. Colloquially called a "virgin birth," this occurs through a process called parthenogenesis, wherein a female animal creates an embryo from an ...