Kow Swamp: is it Homo erectus?

Here is what creationist Marvin Lubenow says about some Australian fossil skulls such as Kow Swamp, Mossgiel, Cohuna, Talgai, and WLH-50:

While evolutionists have not yet developed a formal definition for Homo erectus, a suite of characteristics is generally accepted:

Skull low, broad, and elongated.
Cranial capacity 750-1250
Median sagittal ridge
Supraorbital ridges
Postorbital constriction
Receding frontal contour
Occiptal bun or torus
Nuchal area extended for muscle attachment
Cranial wall unusually thick overall
Brain case narrower than the zygomatic arch
Heavy facial architecture
Alveolar (maxilla) prognathism
Large jaw, wide ramus
No chin (mentum)
Teeth generally large
Post-cranial bones heavy and thick
Where there is material for comparison, the Kow Swamp fossils, as well as the other robust Australian fossils, fit the above description well -- allowing for reasonable genetic variation. They qualify as Homo erectus, as the evolutionist uses the term. (Lubenow, 1992)

I asked Dr. Peter Brown to comment on this claim that the robust Aboriginal fossils should be classified as Homo erectus. Brown is an Australian paleoanthropologist, and one of the few people who has worked with the Kow Swamp skulls and other Australian fossils. Here is Brown's response (lightly modified to include information from my follow-up queries).

Dear Jim,

I have not bothered to discuss the issue of whether H. erectus are deformed or not as from a biological perspective it is so obvious that they are not. For example while the Kow Swamp, Coobool and Nacurrie crania have flattened frontal bones the cranial vaults are high (unlike H. erectus), particularly those which are deformed (basion not preserved at Kow Swamp but mean basion-bregma at Coobool 141 mm, range 134-153). Curvature of the parietals (particularly those which are deformed) is MUCH greater than H. erectus and the occipitals are of modern Aboriginal morphology and not sharply angled at the torus like in H. erectus. Maximum cranial breadth is found high on the parietals, supraorbital region is NOTHING like H. erectus, particularly laterally, bone in the basal part of the vault is not thickened, etc, etc. All of the features which distinguish modern Aboriginal crania from H. erectus work with terminal Pleistocene Australian crania as well. Just happens that late Pleistocene Australians were about 8% larger and more robust than their contemporaries and a few of them had their heads deformed.

As to the characters in Lubenow's list:

1. Skull low, broad, and elongated.

The KS, Coobool and Nacurrie crania are not low. The deformed crania are very high (very unlike H. erectus) and the rest fall within the modern Aboriginal range.

2. Cranial capacity 750-1250

Endocranial volume for WL50 is about 1500 ml (big vault, but pathological) and Coobool Creek mean is 1404 for males (modern Aborigines 1271).

3. Median sagittal ridge

Median sagittal ridge fairly common in modern males throughout Australia (and Asia as well), rare in females. Not diagnostic of H. erectus.

4. Supraorbital ridges

Moderate supraorbital development. True torus VERY rare. Nothing at all like H. erectus.

5. Postorbital constriction

Yes, but this is simply a function of a VERY large masticatory apparatus, well developed temporal muscles and a diet which traditionally required lots of chewing, and the long head shape of Aborigines lends itself to greater postorbital constriction. Importantly postorbital constriction at Kow Swamp not outside the range of recent prehistoric Aborigines, but less than in H. erectus.

6. Receding frontal contour

Aboriginal crania have a more receding frontal contour than Europeans. Not greater at Kow Swamp or Coobool except in deformed crania, some of which have a MUCH flatter frontal bone than in Homo erectus as do artificially deformed Native American crania. But flat frontal bones are not the same as a receding cranial profile. The clearest sign of deformation is the flattened frontal bone on a very high vault with minimal curvature in the occipital region. H. erectus crania have a long low vault with a sharply angled occipital at the occipital torus. [See Brown 1981]

7. Occiptal bun or torus

Occipital torus common in males but the morphology of the occipital region is nothing like H. erectus.

8. Nuchal area extended for muscle attachment

Prehistoric Aborigines had a large area of neck muscle attachment comparable to hunter gatherers in other parts of the world, but not extended as in H. erectus. Quite petite at Kow Swamp: KS5 had a small area of neck muscle attachment, KS1 had more but the occipital is incomplete. All of the Kow Swamp skulls are relatively large, so they have correspondingly large areas of muscle attachment but they all fall within the range of recent prehistoric Aborigines in this respect.

9. Cranial wall unusually thick overall

Cranial vault wall is thickened but the pattern is not like that in H. erectus. See my article on vault thickness in the Pithecanthropus volume (J.L.Franzen (ed) 1994. 100 years of Pithecanthropus. The Homo erectus problem. Courier Forschunginstitut Senckenberg 171)

10. Brain case narrower than the zygomatic arch

Brain case is normally narrower than zygomatic arch but this is to be expected in a dolicochephalic vault with a well developed masticatory system. Homo erectus crania all have long and low vault, with relatively great breadth across the zygomatic arch and marked postorbital constriction. No modern humans, or their ancestors in the last 20,000 years, approach the H. erectus condition.

11. Heavy facial architecture

Facial architecture is not what I would describe as heavy. Big palates, big teeth and reasonable supraorbital development but mid face (zygomatics) are delicate in Aboriginal crania. VERY marked contrast to H. erectus crania like Sangiran 17.

12. Alveolar (maxilla) prognathism

Big teeth, big palates, prognathic faces. The general evolutionary trend has been for a reduction in masticatory system architecture over the last 100,000 years. This trend continued until around 6,000 years ago.There are arguments about the degree to which this is linked to technological change and food preparation. In some parts of the world this trend appears to have proceeded more slowly. This may be because the hunter gatherer masticatory environment maintained strong selection for large teeth. It is hard to find absolute differences between the teeth of terminal Pleistocene Aborigines and Homo erectus but the most obvious one is in the molar size sequence. In H. erectus the smallest molar is usually the first, next largest the 2nd and largest the third. In Aborigines the largest molar is usually the second. In Europeans and east Asians the largest molar is usually the first.

13. Large jaw, wide ramus

Large mandible due to large teeth. H.erectus has a broad ramus while all Aborigines, including Kow Swamp, are narrow.

14. No chin (mentum)

Most aboriginal mandibles have a chin but it is not as prominent as in Europeans. This is what you would expect with larger teeth and greater alveolar development.

15. Teeth generally large

Teeth large, particularly molars, but tooth size pattern not like H. erectus. Largest molar normally M2, followed by M1 and M3. In erectus, M1 is smallest, M3 largest.

16. Post-cranial bones heavy and thick

Postcranial bones are not heavy and thick. Lightly built tropical hunter/gatherers. Postcranial skeletons not as robust as urban Europeans or Asians, let alone Homo erectus.

Hope this helps.

Best wishes, Peter.

Dr. Peter Brown
Senior Lecturer in Palaeoanthropology
University of New England
Australia

In summary, the Kow Swamp and other robust Australian skulls do not fit the definition of Homo erectus

They do have a fairly receding forehead (6), but this is caused by cranial deformation; there are clear signs of deformation in these skulls which are not found in H. erectus (Brown 1981). In a few characteristics correlated with their larger teeth (5, 10, 12, 14, 15), the Kow Swamp skulls resemble H. erectus more than most other modern humans, but are still are generally outside the H. erectus range. But most of Lubenow's criteria for H. erectus do not fit the Australian skulls at all well (1, 2, 4, 7, 8, 9, 11, 13, 16).

References

Brown P. (1981): Artificial cranial deformation: a component in the variation in pleistocene Australian aboriginal crania. Archaeology in Oceania, 16:156-67.

Lubenow M.L. (1992): Bones of contention: a creationist assessment of human fossils, Grand Rapids,MI:Baker Books.

Australian Palaeoanthropology, by Peter Brown

Kow Swamp, by Peter Brown

Artificial Cranial Deformation, by Patricia Lindsell

Kow Swamp: is it Homo erectus? a counterpoint, by Jim vanHollebeke

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