Homo habilis: is it an invalid taxon?

In recent years, the most widely-used creationist argument for dismissing Homo habilis is one popularized by Marvin Lubenow in his 1992 book Bones of Contention. Lubenow argued that habilis was a mixture of at least two species: some of the specimens, such as ER 1470, are humans, while others, such as ER 1813 and OH 24, are apes. As such, Lubenow concluded, H. habilis was not a valid species.

The fossils which have been attributed to habilis are very diverse, and virtually all scientists now agree that they belong to at least two species. Moreover, there is much disagreement about which fossils should be assigned to which species. As Richard Leakey put it in the book Origins Reconsidered:

Of the several dozen specimens that have been said at one time or another to belong in this species [habilis], at least half probably don't. But there is no consensus as to which 50 percent should be excluded. No one anthropologist's 50 percent is quite the same as another's. (Leakey and Lewin 1992)

Similar statements by other scientists are not hard to find. Based on them, creationists have taken to claiming that even mainstream scientists have abandoned habilis as a valid species. For example, an article at the Answers in Genesis website by Carl Wieland (Skull wars: new Homo erectus skull in Ethiopia) claims that:

So-called Homo habilis has pretty well died as a taxon, the confusion seemingly caused by assigning of either erectus or, more commonly, australopithecine fossil pieces into this 'taxonomic waste bin'. (Wieland 2002)
and another article at the same site (rebutted here by Colin Groves) says that:
Homo habilis is now widely recognized as a mixture of different types, technically called an 'invalid taxon'.

What creationists do not understand is that when scientists say that habilis may consist of two or more species, they are not saying that habilis is an invalid species. The reason is that one of those species is Homo habilis. Habilis would be an invalid species if, and only if, its type specimen, OH 7, was determined to belong to a previously defined species. That has not happened and almost certainly will not happen, for the reason that OH 7 differs from all previously named species. (Note that some scientists, for example Wood and Collard (1999), have argued that habiline fossils should be reassigned to the australopithecines, but they are not saying habilis is an invalid species, merely that it should be Australopithecus habilis, not Homo habilis.)

None of this should come as any surprise, incidentally. Anyone who reads either scientific papers or popular articles on paleoanthropology will quickly see that habilis is alive and well, and routinely referred to. I am not offhand aware of any paleoanthropologists who consider habilis an invalid species.

Ronald Gravendeel, a Dutch Ph.D. student in biology, queried the above statement by Carl Wieland and asked for references for it. In AIG's response to Gravendeel (Homo erectus misunderstandings?), Carl Wieland elaborated, giving a source for his claim:

For some years now, most evolutionist specialists nowadays agree that H. habilis was probably always a phantom taxon, with a bag of fossils belonging to either H. erectus/ergaster or to australopithecines thrown into this 'taxonomic wastebin' (we have a video, The Image of God, for sale on our Web site which makes this plain, through an interview with Dr Fred Spoor, a Dutch-born paleoanthropologist in the UK, and joint editor of the Journal of Human Evolution. But it is 'common knowledge'.) (Wieland 2002)
(An earlier version of this article stated even more forcefully that "Frankly, this is such common knowledge that this question seems as quaint as asking for a reference that water contains hydrogen and oxygen.")

AIG obviously thinks that Spoor gives conclusive proof that habilis is an invalid species. So, what did Fred Spoor say on The Image of God about habilis' supposed demise? Here it is:

"I guess a majority of researchers now feel that what we used to call Homo habilis is not a single species but is a kind of wastebin of various fossils that are grouped together and kind of intermediate between australopithecines and Homo erectus and lets all call it one name and we don't know ... but more and more people recognize that there's at least two species and maybe even more." (Fred Spoor, on The Image of God video)
Contrary to Wieland's assertion, nothing in there actually says that habilis is an invalid taxon. Spoor did not say that habilis was not a valid species; he said that it was not a single species (more precisely, that the fossils often assigned to habilis do not all belong to a single species). The meaning of this seems perfectly clear, though apparently not to the folks at AIG. In fact, Spoor explicitly states that the habilines are "kind of intermediate" between the australopithecines and Homo erectus. I contacted Fred Spoor to ask him whether the AIG claim fairly represented his views.
Q: For the record: do you believe H. habilis is an invalid taxon?
Spoor: The species name "habilis" is a valid taxon, whether it is included in the genus Homo, Australopithecus or any other.

Q: Or, as I suspect, do you consider it a valid species to which specimens from other species have been mistakenly attributed?
Spoor: Correct. The question is simply figuring out which fossils represent the same species as the type specimen of H. habilis (a mandible from Olduvai, Tanzania). Over time, when more fossils will be found, we will get an increasingly good idea about morphological variation of this species, and what type of cranium exactly fits with the type mandible.

Q: If you don't have the video in question, I do, and can tell you exactly what you said if you are interested.
Spoor: I don't have the video myself (only polite journalists send copies to the people they interview; this interview was conducted without disclosing the creationists' agenda). In any case, at the time I must have discussed the status of Stw 53 from Sterkfontein. I thought and think that it is unlikely to be H. habilis, and colleagues increasingly support that view. In fact, officially Philip Tobias only preliminarily referred this specimen to Homo cf habilis, i.e. it was never formally assigned to that taxon.

Keep up the good work disclosing the creationists' nonsense. I am very much aware that any arguments and disagreements in scientific debates between palaeoanthropologists will be taken out of context and used by creationists to suggest that they have science and actual evidence on their side. Once we get into further debate about the status and implications of Kenyanthropus platyops, I am sure they will (ab)use that too....

Amen. What is 'common knowledge' to the folks at Answers in Genesis turns out to be not knowledge at all, but a fantasy born of their lack of reading comprehension. Homo habilis is still a valid species.

P.S.: (February 2003) The latest development with Homo habilis is the discovery of the fossil OH 65 which, according to its discoverers (Blumenschine et al. 2003), may lead to a reassessment of the habiline fossils, and of which fossils belong to Homo habilis proper. Creationists may claim this uncertainty supports their contention that habilis is an invalid taxon, but in fact it disproves it: Blumenschine and his colleagues would hardly be arguing about which specimens belonged in habilis if they didn't consider it a valid species. They do, and so does the rest of scientific community.

Back to the Creationist Arguments: Homo habilis page

Review of the video The Image of God

This page is part of the Fossil Hominids FAQ at the talk.origins Archive.

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