Numerous fossils of Apes that existed before the advent of Homininds
have been discovered in Kenya. As is the case with Human evolution
fossils, Kenya is fertile ground for the discovery of ancient Ape
fossils. Below is a listing, description and
background information about the Human evolutionAncient Ape fossils
unearthed in Kenya.

The Oldest Chimpanzee Fossils

As of 2015, the oldest chimpanzee fossils ever found were unearthed

in the Kapthurin Formation, a section of the Rift Valley near
Kenya’s Lake Baringo. These fossils, consisting of three teeth, dated to
500,000 years in age–meaning that chimpanzees coexisted alongside
hominids. They were unearthed by Sally McBrearty.

Chimpanzee fossils are very rare because they  tend to live in
hot, wet jungle conditions that are not good for the preservation of
remains

Nakalipithecus Nakayamai

Nakalipithecus Nakayamai is an ape that existed 9.9 to 9.8 million
years ago. It is known from a jawbone that was unearthed in the Nakali
region of Kenya by a team of Kenyan and Japanese scientists. The genus
assigned after the area it was found in while the species is named after
Japanese geologist Katsuhiro Nakayama who died while working on the
project.

Nakalopthecus Nakayamai jawbone.
Credit: Yutaku Kunimatsu

Nakalipithecus is very close to the last common ancestor of Humans,
chimpanzees and  Gorillas. Its dental features resemble those of
Ouranopithecus macedoniensis, an ape that lived in what is now
Greece between 9.6 million and 8.7 million years ago and which some
scientists think is the last known common ancestor to African great apes
and humans. Together with Ouranopithecus it provides evidence
that the Homininae lineages of today diverged no earlier than some 8
million years ago. Second, it supports the theory that the closest
relatives of humans evolved in Africa.

Kamoyapithecus Hamiltoni

Kamoyapithecus is an ape that lived during the Oligocene period (27
million. It was first discovered in 1948 and was initially thought to be
a form of proconsul. It was later re-examined by reknowned
palaentologist Richard Leakey and assigned a new genus Kamoyapithecus in
honour of famous  fossil finder Kamoya Kimeu.

Kamoyapithecus is the oldest known Catarrhine (Catarrhines are one of
the two subdivisions of higher primates).

Kamoyapithecus is only known from tooth and jaw fragments. Its teeth
are not thickly ernamelled. As such it is thought to have fed primarily
on soft foods such as fruits and seeds.

Proconsul

Photo: Univ of Zurich

The Proconsul are an extinct genus of Ape whose fossils have been
discovered in Kenya and Uganda. It existed during the miocene epoch
(23-25 million years ago). There are four species: P. africanus,
P. gitongai , P. major and P. meswae, which defer
in body size.

Proconsul show a mixture of Ape and Old world monkey characteristics.
Monkey like features include flexible back, curved metacarpals, and
monkey like posture. Its ape like features include the lack of a tail
and enhanced grasping capabilities.

Because it is one of the earliest monkey to Ape transitional species,
It is thought to be a strong candidate to be the ancestor of all great
Apes including man and chimpanzees.

The first specimen was discovered at Koru in what is now Kisumu county
in 1909. It was the first ever fossil mammal found in Sub Saharan
Africa. Additional fossils were found near Lake Victoria and on Rusinga
Island.

Kenyapithecus

This genus was first discovered at Fort Ternan by Louis Leakey in
1962. It was dated to 14 million years ago. There are two species: K.
Wickeri and K. Africanus, however there is still great debate among
scientists about its classification. It is considered as a potential
ancestor to the great Apes. Since very similar fossils have been found
in Turkey, it is also considered as one of the Apes that started the
radiation out of Africa.

Samburupithecus Kiptalami

Samburupithcus Kiptalami is known from a maxilla fragment that was
discovered in 1982. It was dated to 9.5 million years ago. It is the
only species of the genus Samburupithecus.

The teeth have a thick coating of enamel and have cusps that are more
rounded rather than pointed.‭ ‬This suggests a diet that incorporated
tougher vegetation.

Limnopithecus

Limnopithecus was a a genus of fossil nonbrachiating gibbon like ape from the Lower Miocene. It was similar in size to modern Gibbons, weighing about 5kg. The species found in Kenya was Limnopithecus Legetet, which is also the oldest (20 – 18 million years. It was found on the Wayondo formation on Rusinga island.

Limnopithecus was initially theroized to the ancestral to gibbons, but scientists are  now it is more inclined to consider it an archaic hominoid, part of a basal stock that also includes the ancestors of the ilobatids and hominids. Affinities have been proposed with Dendropithecus.

It is assumed that Limnopithecus was an arboreal animal that moved easily between the branches; it probably fed on leaves and fruit.

Dendropithecus

Dendropithecus was a genus of ape that existed 15 to 20 million years ago. It was Gibbon like but with very primitive features. It was 60 cm in length and was able to brachiate. Its remains were found on Rusinga island.