The polar regions are the coldest places on Earth. During the summer, the poles receive 24 hours of sunlight, but during the winter the sun is rarely visible. Animals that inhabit nature’s freezers ...

Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient world slept only 6.5 hours a night.

Many of the bird species that arctic foxes hunt during the summer migrate south to escape the harsh winter weather. The foxes ...