Ancient mammals that lived in the time of dinosaurs were mostly the same dark-brown colour, according to a new study providing clues about how those mammals evolved as they faced giant predators.

Both usually produce few young at one time, and ensure their survival by caring for them. Unlike mammals, birds lay eggs and initial stages of development occur outside the mother’s body. Reproductive ...

Both usually produce few young at one time, and ensure their survival by caring for them. Unlike mammals, birds lay eggs and initial stages of development occur outside the mother’s body. Reproductive ...