The Hominini (hominins) form a taxonomic tribe of the subfamily Homininae (hominines). They comprise two extant genera: Homo () and Pan ( and ), and in standard usage exclude the genus Gorilla (), which is grouped separately within the subfamily Homininae.
The term Hominini was originally introduced by Camille Arambourg (1948), who combined the categories of Hominina and Simiina pursuant to Gray's classifications (1825).
Traditionally, , and were grouped together, excluding humans, as pongidae. Since Gray's classifications, evidence accumulating from genetic phylogeny confirmed that humans, chimpanzees, and gorillas are more closely related to each other than to the orangutan.[ Still, details of this reassignment remain contested, and of publishing since (on tribe Hominini), not every source excludes gorillas and not every source includes chimpanzees.
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Humans are the only extant species in the Australopithecine branch (subtribe), which also contains many extinct close relatives of humans.
Terminology and definition
Concerning membership, when Hominini is taken to exclude Pan, Panini ("panins")
By convention, the adjectival term "hominin" (or nominalized "hominins") refers to the tribe Hominini, whereas the members of the subtribe Hominina (and thus all archaic human species) are referred to as "homininan" ("homininans").
The alternative convention uses "hominin" to exclude members of Panina: for Homo; or for human and australopithecine species. This alternative convention is referenced in e.g. Coyne (2009)[ Potts (2010) in addition uses the name Hominini in a different sense, as excluding Pan, and uses "hominins" for this, while a separate tribe (rather than subtribe) for chimpanzees is introduced, under the name Panini.][ In this recent convention, contra Arambourg, the term "hominin" is applied to Homo, Australopithecus, Ardipithecus, and others that arose after the split from the line that led to chimpanzees (see cladogram below);]
Cladogram
This cladogram shows the clade of superfamily Hominoidea and its descendant clades, focused on the division of Hominini (omitting detail on clades not ancestral to Hominini). The family Hominidae ("hominids") comprises the tribes Ponginae (including ), Gorillini (including ) and Hominini, the latter two forming the subfamily of Homininae. Hominini is divided into Panina () and Australopithecina (australopithecines). The Hominina () are usually held to have emerged within the Australopithecina (which would roughly correspond to the alternative definition of Hominini according to the alternative definition which excludes Pan).
Genetic analysis combined with fossil evidence indicates that hominoids diverged from the Old World monkeys about 25 million years ago (Mya), near the Oligocene-Miocene boundary.
Evolutionary history
Both Sahelanthropus and Orrorin existed during the estimated duration of the ancestral chimpanzee–human speciation events, within the range of eight to four million years ago (Mya). Very few fossil specimens have been found that can be considered directly ancestral to genus Pan. News of the first fossil chimpanzee, found in Kenya, was published in 2005. However, it is dated to very recent times—between 545 and 284 thousand years ago.
Most DNA studies find that humans and Pan are 99% identical,
All the listed fossil genera are evaluated for two traits that could identify them as hominins:
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probability of being ancestral to Homo, and
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whether they are more closely related to Homo than to any other living primate.
Some, including Paranthropus, Ardipithecus, and Australopithecus, are broadly thought to be ancestral and closely related to Homo;
List of known hominin species
Extant species are in bold.
Gallery
See also
External links
