Life › The age of mammals › Primates
Apes
by c. 25 million years ago· Organism or group· Human ancestors & us
Strong evidenceGood evidence; dates or details still being refined.
Tailless primates with flexible shoulders, including gibbons, orangutans, gorillas, chimpanzees, bonobos and humans.
See it on the Life map →What happened
Apes, or hominoids, have no tail, shoulders that let them hang and swing beneath branches, larger brains and slow-growing young. They split from Old World monkeys roughly 30–25 million years ago; Rukwapithecus from Tanzania, about 25 million years old, is among the earliest. In the Miocene, about 23–5 million years ago, dozens of ape species lived across Africa, Europe and Asia. Today only gibbons, orangutans, gorillas, chimpanzees, bonobos and humans remain, most of them endangered.
Why it matters
Humans are apes. Ape anatomy, especially the upright trunk and flexible arms, laid groundwork for walking on two legs and using tools.
The evidence (fossils, genes, rocks)
Miocene fossils such as Proconsul (Kenya), Rukwapithecus (Tanzania, described 2013) and Sivapithecus (South Asia), plus DNA: humans and chimpanzees differ by only about 1–2% in aligned DNA.
Still debated
Which Miocene apes led to living great apes is unclear, and some argue the human–chimp ancestor descended from apes that returned to Africa from Europe.
Inside this (1)
Connections (3)
▸Monkeys & other anthropoids branched into ApesWell established
The connection
Old World anthropoids, the catarrhines, split roughly 30–25 million years ago into two branches: Old World monkeys, such as baboons and macaques, and apes. Apes lost the tail and evolved flexible shoulders for hanging below branches. Apes did not descend from living monkeys; both share an earlier catarrhine ancestor, something like Egypt's Aegyptopithecus.
When and how
Africa, about 30–25 million years ago; fossils from Tanzania's Rukwa Rift, described in 2013, include the earliest known ape and Old World monkey.
The evidence
The 2013 Tanzanian fossils, about 25 million years old, match the split time predicted by DNA from living monkeys and apes.
Debates and open questions
Why apes declined while Old World monkeys flourished after about 10 million years ago is debated; diet and breeding speed are leading ideas.
▸Proconsul is an early member of ApesWell established
The connection
Proconsul combines an ape's tailless body and ape-like teeth and skull with a monkey-like way of moving along branches on all fours. That mix suggests the first apes looked rather like monkeys, with ape traits arriving piecemeal. It lived about 21–17 million years ago, early in the Miocene ape boom.
When and how
Western Kenya, including Rusinga Island in Lake Victoria; named by Arthur Hopwood in 1933, with the famous skull found by Mary Leakey in 1948.
The evidence
Skeletons show no tail and ape-like teeth and skulls; family-tree analyses usually, but not always, place it among the apes.
Debates and open questions
Some studies place Proconsul just outside the apes, as a close cousin; its species have been split into several genera, such as Ekembo.
▸Apes gave rise to Hominins: the human branch beginsWell established
The connection
Among African apes, the line leading to humans split from the one leading to chimpanzees and bonobos; gorillas had branched off earlier, about 10–8 million years ago. Early hominins kept many ape traits, including small brains and climbing ability, but began walking upright and evolved smaller canine teeth.
When and how
Africa, roughly 7–6 million years ago; DNA-based estimates range from about 5 to 10 million years ago, depending on assumed mutation rates.
The evidence
DNA shows humans are most closely related to chimpanzees and bonobos, and early hominin fossils appear in Africa within the predicted time window.
Debates and open questions
The human–chimp common ancestor has never been identified, and fossil chimpanzees are almost absent, apart from a few teeth from Kenya (2005).