Every animal with a brain needs sleep — and even a few without a brain do, too. Humans sleep, birds sleep, whales sleep and even jellyfish sleep.

Most people picture sleep as a single block of rest at night, maybe stretched a little longer on weekends. Penguins live by a different rhythm. Their idea of rest is broken into countless flickers of ...

The critically endangered African penguin has several predators to fear, including gulls, seals and sharks at sea, and leopards, caracals, domestic dogs and mongoose on land. A recent study has now ...