Gorilla
Gorillas are ground-dwelling, predominantly herbivorous apes that inhabit the forests of central Sub-Saharan Africa. They are classified in the genus Gorilla which is divided into two species: the eastern gorillas and the western gorillas (both critically endangered), and either four or five subspecies. They are the largest living primates. The DNA of gorillas is highly similar to that of humans, from 95 to 99% depending on what is included, and they are the next closest living relatives to humans after the species of "Pan"; the chimpanzees and bonobos.
Biretia
The smallest of the species, "B. fayumensis", had an estimated weight of 273 g, while the largest, "B. megalopsis", had a weight of about 376g. Adaptations of the skull of "B. megalopsis" are easily comparable to the modern tarsiers, a small, modern Asian primate with a nocturnal insectivorous lifestyle. We can infer the possibility of a nocturnal lifestyle for "B. megalopsis"' from the animal's molar roots, which are truncated to accommodate for large eye sockets typical of a nocturnal primate. The large eye structure and similarity to the modern tarsiers also suggests that it has lost its tapetum lucidum. Thus, "B. megalopsis" demonstrates itself as being the oldest known nocturnal primate.