An estimated 1.75 million ibises were deposited at a single location in ancient Egypt. But the birds disappeared entirely from the region around 1850, and no one knows why.
Ritual feasting emerged around the time humans were beginning to farm. It came to play an important role in societal bonding, much as it does today.
New evidence suggests that Homo naledi didn't deliberately deposit their dead in a hidden chamber.
Groundbreaking video footage could change the way we look at chimpanzees.