An ancient Martian system of canyons and valleys could be home to archaic life forms, a ground-breaking scientific paper has found. Scientists investigating the Red Planet’s mind-boggling cave system ...

Debunking alien claims matters, but so does telling richer, more compelling stories about how humans shaped their own past.

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...