These included the first fully aquatic mammals (whales ... at scales both large and small, in evolutionary history.

Dolphins live and hunt in large social groups called pods, and they communicate with each other using high-pitched clicks and ...

Marine mammals—a group of animals that are ecologically tied to the ocean environment—cannot thrive in confinement. No concrete tank or small sea pen can provide an animal with anything close to the ...

The head is broad and flat with short, rounded ears and small eyes ... burrows of other mammals. Otters also dwell in abandoned beaver lodges, hollow logs, under tangles of roots, and within rocky ...

Aquatic – Any animal that lives or feeds ... Foxes are an example of an omnivorous mammal. Rodent – A small mammal with a pair of long front teeth used for gnawing. Rats, mice, hamsters ...

It's the tale of an ancient land mammal making its way back to the sea ... and all of its vital systems became adapted to a marine existence -- the reverse of what happened millions of years ...