Why do giraffes have long necks?

The giraffe is the tallest animal in the world: an adult male can be almost six meters tall. Much of that height is its very long neck. What is it for and how did it get that way?

Eating up high

The main reason is food. Giraffes eat leaves, especially from acacia trees, and with their long neck they reach the highest branches, where almost no other animal can. They also use a very long tongue, about forty-five centimeters, dark and tough.

Seven bones, just like you

Incredible as it seems, a giraffe neck has only seven vertebrae, just like yours. The difference is that each of theirs is more than twenty centimeters long.

How it evolved

Scientists think that, millions of years ago, giraffes with slightly longer necks found more food and survived better, so they had more young. Over very many generations, the neck grew longer. We call this process natural selection.

A super-powerful heart

To get blood up to the head, a giraffe heart is huge and pumps very hard. Special valves in the blood vessels stop the blood from rushing to the head when the animal lowers its neck to drink.

Drinking, sleeping and moving

To drink, a giraffe spreads its front legs wide and lowers its neck. It sleeps very little, sometimes less than two hours a day, and often standing up. Although it looks clumsy, it can run at more than fifty kilometers an hour.

A fun fact

Every giraffe has a unique pattern of spots, like a fingerprint. Calves are born standing up and are almost two meters tall from the first day.

Activity: measure like a giraffe

Tape a tall strip of paper to the wall and mark how high you can reach with your arms stretched up. Compare it with a giraffe height: it is about the same as three adults standing on top of each other.