Posted on Monday 11 April 2005

After examining detailed images of the bones of Ebu Gogo, John Hawks has now come out unambiguously on the side of Jacob, Thorne and Henneberg . He now thinks that the Homo floresiensis skull and bones are definitely indicative of some sort of kind of pathology and one that is in a single individual rather than the contemporary population. He doesn't go on to speculate what this pathology is other than it disqualifies in his mind the possibility that this represents a new species. Professor Teuku Jacob has argued since the beginning that the bones are most likely those of a pygmy human being (a type that still inhabits the region) albeit one with some sort of growth abnormality such as microcephaly.

I've been following John's blog for quite a while and he has always had something interesting to say in the Ebu Gogo debate. Previously, he has even floated the possibility that the bones might have been australopithecine , an extremely archaic human type distinct from Homo erectus. He now emphatically disavows ...

...any suggestion that LB1 or any of the Flores fossils are australopithecines. Along with four of the best anatomists that I know, I had the opportunity to see detailed pictures of the LB1 postcrania.

The specimen is beyond any doubt or question pathological.

This is very clearly shown by many details that are either not depicted or are not clear in the photos in the original Nature paper. It is not my place to provide more information about these details; my understanding is that a thorough presentation of them is forthcoming. I will say that this specimen has morphological characters that would indicate severe developmental abnormalities even if the skull had never been found . This is in no way a close call.

It remains to be shown whether the pathology in the specimen explains its brain size. Examination of the endocast shows features that are highly unusual. It would seem to me remarkable if the occurrence of these features was purely coincidental with the postcranial and cranial pathology.

My suggestion of australopithecine affinity was based strongly on the anatomy of the pelvis and the size of the brain. Since the specimen is pathological, I no longer trust that either feature characterized the Flores population rather than this single individual.

I also saw the other skeletal specimens. These have not been described, so I will not talk about them, although their existence has been widely cited as evidence that LB1 was typical of its population. A look at the rest of the sample lends little credence to this idea.

The bottom line is that this specimen cannot be assumed to be representative of the population from which it came. Any interpretation that starts with the assumption that LB1 is normal should be viewed with extreme skepticism.