Apes are primates that belong to the superfamily Hominoidea which is split into gibbons and great apes. We are estimated to share over 98% of our DNA with chimpanzees with whom we shared a common ancestor as recently as eight million years ago. All apes lack a tail – an adaptation thought to be associated with the evolution of brachiation (swinging below the branches of the trees).
Gibbons (Family Hylobatidae) are known for their ability to swing great distances from branch to branch in the forest canopy. Like other members of this superfamily, gibbons lack a tail and hold themselves in a semi-erect posture. They have many features in common with humans but are considered to have low cognitive ability.
The Family Hominidae consists of only eight extant species of ape in four genera; Pongo (orangutan), Gorilla (gorilla), Pan (chimps and bonobos) and Homo (humans). All Hominidae share complex cognitive abilities including the ability to recognize themselves in mirrors (indicating a degree of self-awareness), and as far as is known they are the only animals (with the exception of the bottlenose dolphin) that can do this.