The Great Apes - gorillas, bonobos, chimpanzees, orangutans Lesser Apes - gibbons, siamangs Apes are larger, do not have tails, have short and broad noses, have larger brains, and are capable of using tools and learning language Humans are considered part of the Great Apes sub-group. The first apes evolved about 25 million years ago. They branched out as a diverse group by 20 million years ago. Within the last 10 million years, many ape species became extinct as the Earth cooled and the forests turned into woodland and grassland. There are now only 20 living species of apes.