African penguin

Like our fingerprints, each penguin's feather pattern is unique. The flecks across their white chests are a way to distinguish one penguin from another.

Each individual also has its own distinct calls. There are three different types of calls: a bray to attract a mate; the yell to defend their territory; and the haw, used by mates to locate each other.

You can tell if a penguin is angry by its body language too — chest puffed, wings back, beak forward and head bobbing.

A suit of dense, waterproof feathers keeps them dry and warm when they dive in the cold waters off the African coast. Look closely and you will see the penguins have a small pink gland above each eye. This feature helps them to cope with soaring temperatures in the day, The glands take on a pinker appearance as the weather warms up. When a penguin gets hot, more blood is sent to these glands, where it is cooled by the surrounding air, thus keeping the bird cool.