Saturday, November 06, 2010

Wolf and dog, Neandertal and human, and the limits of taxonomy

Laypersons think of wolves and dogs (Canis lupus familiaris) as different species. That is not so, though the taxonomy is confused (see wikipedia page on "disambiguation" of the term Wolf).

Canis lupus includes domestic dogs and all "wolves", each as a "subspecies". So Huskies and Great Danes and Chiwawa are all Canis lupus familiaris, whereas the Husky-like wolf is a different subspecies.

A Wolf in truth, is simply a Canis lupus subspecies that is not domesticated, and a Dog is a Canis lupus subspecies that is domesticated (Canis lupus domesticus).

Canis lupus used to be the most widely distributed of all mammals, until humans took that spot.

Humans being "Homo sapiens", sometimes called "Homo sapiens sapiens" (see the problem?);  a species distinct from  Homo neanderthalensis and other Homo.

But if it is accepted that our most common ancestor interbred with Homo neanderthalensis to create us, shouldn't we follow the example of the Canids? Living humans might be considered Homo sapiens domesticus, Neanderthals would be Homo sapiens neanderthalensis, and Homo heidelbergensis would  be Homo sapiens heidelbergensis.

Of course if we follow the wolf example we'd probably start carving up Homo sapiens domesticus based on fur color and ancestral ranges. So at some point we probably need to admit taxonomy has its limitations.

PS. I wrote this post because Google couldn't find any other posts comparing the fraught and confusing taxonomy of Canis lupus with the even more fraught taxonomy of Homo sapiens. I think it's curious that we should have so much trouble classifying the two species we know best.

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