Leaf insects, also known as walking leaves, are masters of camouflage that mimic plant foliage in detail.
In 1963, Randy Gardner stayed awake for 264 hours (11 days) as part of a sleep-deprivation experiment.
A brain scan of a typical brain (left) compared to an anonymous patient known as S.M. Patient S.M. was born with a condition called Urbach-Wiethe disease, which damaged her amygdala and left her virtually incapable of feeling fear.
