Only the youngsquirrel monkeys use their long tail to grip things.
Squirrel monkeys are a small species of ape  which is widespread throughout the forests of the Amazon basin. They  have mask-like markings on their faces and a black snout. Their body is  covered in thick, short fur which varies between shades of grey and  green. Their hands are usually yellow-orange while their stomach is  often white. Thanks to their long tails squirrel monkeys are skillful  climbers which feed mostly on insects and fruit. A group of squirrel  monkeys can comprise up to one hundred animals led by the most senior  female.