The gibbon–human last common ancestor is the

last common ancestor A most recent common ancestor (MRCA), also known as a last common ancestor (LCA), is the most recent individual from which all organisms of a set are inferred to have descended. The most recent common ancestor of a higher taxon is generally assu ...

of the superfamily

Hominoidea Apes (collectively Hominoidea ) are a Family (biology), superfamily of Old World simians native to sub-Saharan Africa and Southeast Asia (though they were more widespread in Africa, most of Asia, and Europe in prehistory, and counting humans ...

(apes), dating to the split of the

Hylobatidae Gibbons () are apes in the Family (biology), family Hylobatidae (). The family historically contained one genus, but now is split into four extant genera and 20 species. Gibbons live in subtropical and tropical forests from eastern Bangladesh an ...

(gibbons) and

Hominidae The Hominidae (), whose members are known as the great apes or hominids (), are a taxonomic Family (biology), family of primates that includes eight Neontology#Extant taxa versus extinct taxa, extant species in four Genus, genera: ''Orangutan ...

(great apes) families. It is dated to the early

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

, roughly . Hylobatidae has four gibbon genera ('' Hylobates'' with 9 species, '' Hoolock'' with 3 species, '' Nomascus'' with 7 species and '' Symphalangus'' with only 1 species) containing 20 different species. Hominidae has two subfamilies,

Ponginae Ponginae , also known as the Asian hominids, is a subfamily in the family (biology), family Hominidae. Once a diverse lineage of Eurasian apes, the subfamily has only one Neontology, extant genus, ''Pongo (genus), Pongo'' (orangutans), which con ...

(orangutans) and

Homininae Homininae (the hominines) is a subfamily of the family Hominidae (hominids). (The Homininae——encompass humans, and are also called "African hominids" or "African apes".) This subfamily includes two tribes, Hominini and Gorillini, both having ...

(African apes, including the human lineage).

Evolutionary history

A 2014 whole-genome molecular dating analysis indicated that the gibbon lineage diverged from that of great apes (Hominidae) around 17 million years ago (), based on certain assumptions about the generation time and mutation rate. The extinct '' Bunopithecus sericus'' was a gibbon or gibbon-like ape. Adaptive divergence associated with chromosomal rearrangements led to rapid radiation of the four genera within the Hylobatidae lineage between about 7 to 5 Mya. Each genus comprises a distinct, well-delineated lineage, but the sequence and timing of divergences among these genera have been hard to resolve due to radiative speciations and extensive incomplete lineage sorting. Recent coalescent-based analysis of both the coding and noncoding parts of the genome suggests that the most likely sequence of species divergences in the Hylobatidae lineage is (Hylobates, (Nomascus, (Hoolock, Symphalangus))). Though other studies have also found different topology.

Appearance and ecology

Because fossils are so scarce, it is not clear what GHLCA looked like. A 2019 study found that the species was "smaller than previously thought" and about the size of a gibbon. It is unknown whether GHLCA was tailless and had a broad, flat rib cage like their descendants. But it is likely that it was a small animal, probably weighing only . This contradicts previous theories that they were the size of chimpanzees and that apes moved to hang and to swing from trees to get off the ground because they were too big. There might have been an arms race in brachiating to reach the best food. Also, the Hominidae, which came later, were smaller than their ancestors, which is contrary to normal evolution where animals get larger over their evolutionary development.

Evolutionary history

Appearance and ecology

References

See also