Examining why, at some point in evolution, humans began to walk upright.
Monkeys and apes are the most brilliantly colored mammals equipped with attributes that help them attract mates and find food.
A range of adaptations helps tree-dwelling mammals to get around.
Seals, dolphins and whales become the new hunters of the sea.
Omnivores' resourcefulness enables them to take advantage of gluts of some kinds of foods and helps them survive.
Carnivores may hunt alone or in packs.
Agoutis and squirrels have sharp front teeth for opening nuts; kangaroo rats store seeds in elaborate nests and burrows.
Mammals need special tools to acquire food from roots and seeds.
Early mammals consumed insects.
Mammals regulate their temperatures and nurture their young on milk.