Embryo fossil found in South Africa is world’s oldest proof that mammal ancestors laid eggs

Between 280 and 200 million years ago, a group of animals evolved which would eventually give rise to mammals, including humans: the therapsids. They were first described more than 150 years ago, ...

Mammal ancestors laid eggs—and this 250-million-year-old fossil proves it

A remarkable new discovery is shedding light on one of the greatest survival stories in Earth's history, and answering a ...