Colobus monkeys are some of the best leapers in the forest. They can jump 8 metres from one tree to another - that's about the width of a school classroom. They land on their feet, grab the next branch with their hands, and keep going without stopping. A whole troop can travel through the treetops without ever touching the ground.
They eat mostly leaves. Leaves are not very nutritious, so colobus monkeys have to eat a lot of them and spend a lot of time digesting. They have a special tummy with several chambers, a bit like a cow's, that helps break down the tough leaves.
Family groups can have 20 or 30 monkeys in them. Babies are passed between aunts, sisters and friends - a bit like a baby being looked after by the whole street. Mothers can recognise their own baby's call out of dozens of others, even up in the noisy treetops.
Sadly, this monkey is now rare because much of its forest home has been cleared. People in Senegal are working hard to protect the forests in places like the Niokolo-Koba National Park, so that these monkeys can keep leaping through them for generations to come.