Homininans, including us humans, are a type of hominin. Hominins are part of
Homininae.
Hominidae includes hominines. These are all subsets of
Hominoidea.
Confused yet? You should be. Welcome to the not-so-wonderful world of typological, ranked taxonomy.
Traditionally, taxonomy had little to do with how organisms were actually related (Linnaeus having preceded Darwin by a good century). Taxonomy was just a way of sorting specimens: these ones go in this box (a species), and the little box goes in this bigger box (a genus), and the bigger box goes in this even bigger box (a family), and so on.
Eventually a typological system arose from this: one specimen (ideally) would be the standard, the archetype, the name-bearer for a given little box. One little box would be the "type" for a larger box, and so on. The box sizes were also strictly regulated: species, genus, family, order, class, phylum/division, kingdom. Eventually, new intermediate sizes, or ranks, were also added: subgenus, subfamily, superfamily, infraorder, suborder, etc.
Several taxonomic codes arose to govern this style of taxonomy, primarily the
ICZN for fauna and the
ICBN for flora. To simplify matters, they mandated that the name of a type genus should be used with the appropriate suffix for some of the taxa that include that genus. The codes don't agree on which suffixes to use for ranks (for example, the
ICZN uses
-idae for families while the
ICBN uses it for subclasses), but they are standardized within each code.
Under the
ICZN, our own taxonomy below the ordinal level looks like this:
| Rank | Taxon | English vernacular form |
|---|
| Superfamily | Hominoidea | hominoid |
| Family | Hominidae | hominid |
| Subfamily | Homininae | hominine |
| Tribe | Hominini | hominin |
| Subtribe | Hominina | homininan |
| Genus | Homo | — |
| Subgenus | Homo (Homo) | — |
| Species | Homo sapiens | — |
| Subspecies | Homo sapiens sapiens | — |
Anyone whose skin isn't crawling by now isn't paying attention.
Not only are these names comically and confusingly similar, but they're ambiguous. "Hominidae" means "the family that includes
Homo", but what constitutes a "family" is entirely up to the whims of the taxonomist. As I've discussed on this blog earlier, some researchers restrict to to
Homo and a few close, extinct relatives, while others have included all great apes as well, or even all apes.
Recently there has been a movement to coöpt these names into a phylogenetic framework. Something like this is emerging as a consensus (extinct taxa omitted):
Hominoidea
|--Hylobatidae (gibbons)
`--Hominidae
|--Ponginae
| `--Pongo (orangutans)
`--Homininae
|--Gorillini
| `--Gorilla (gorillas)
`--Hominini
|--Panina
| `--Pan (chimpanzees, including bonobos)
`--Hominina
`--Homo
`--Homo sapiens (humans)
In some ways this is a good scheme, but it has two big problems: 1) the
Homo-typified names are still all horribly similar, and 2) many people still use those names in the more traditional way, where, for example,
Gorilla,
Pan, and
Pongo are not in Hominidae.
So here's a brainwave: why not just think of new names for these clades? Seriously!
We already have some good vernacular names as a basis: "apes" for
Hominoidea, "great apes" for
Hominidae, and "African apes" for
Homininae. Admittedly there's not a convenient term for the chimp-human crown group (besides "the chimp-human crown group", of course). Maybe something like "hunting apes" (humans and common chimps are the only apes to go on hunts, I think) or "sexy apes" (humans and bonobos are the only apes to engage in certain sexual positions and activities). Translate these into Latinized Greek and we get:
Pithecoi
|--Hylobatidae (gibbons)
`--Megapithecoi
|--Pongo (orangutans)
`--Afropithecoi
|--Gorilla (gorillas)
`--[insert clever name here]
|--Homo (humans)
`--Pan (chimpanzees, including bonobos)
Isn't that much nicer? All of these could be defined as crown groups (except for
Homo).
Well, just a little dream of mine, anyway....
