Science Literature

The thumbnail portrait of science that most children get in schools is that science is objective and "value-free" knowledge. Science is supposed to reach the same outcomes in whatever culture it is practised and whoever does the research. The simplest response to this is to say that the thumbnail is misleading: science is an activity practised by creative but fallible human beings who bring cultural values into their work, sometimes consciously but mostly unconsciously. A well-written contribution on these issues is by Henry Gee in Nature, reviewing a book by palaeoanthropologist Dean Falk. Her subject is human evolution and the controversies about Australopithecus africanus in 1924 and Homo floresiensis in 2003. Gee begins his review with this iconoclastic paragraph:

"We have all seen the canonical parade of apes, each one becoming more human. We know that, as a depiction of evolution, this line-up is tosh. Yet we cling to it. Ideas of what human evolution ought to have been like still colour our debates."

"This line-up is tosh" - Henry Gee (source here)

The 1924 paper, authored by Raymond Dart, was received with scepticism. Whilst the fossil became known as the "Ape-Man of South Africa", the skull was that of a juvenile. Everyone knows (or should know) that juvenile apes have more human-like characteristics than adult apes. But resistance to Dart's hypothesis came mainly because his peers considered that brain expansion preceded bipedalism and these people defended their thinking by reference to Piltdown Man. Gee sees this as evidence of prejudice affecting the course of science.

"Dart's original paper on A. africanus was, it is true, long on waffle and short on substance. But the reason that this small-brained, possibly erect-walking creature took two decades to be accepted as a hominin was that researchers were in thrall to the idea that the expansion of the human brain came first, before the adoption of a fully erect gait. This preconception was supported by the discovery of the large-brained, ape-jawed Piltdown Man in 1912. The fact that it took 40 years to expose Piltdown as a fraud is a mark of how deeply rooted such prejudices can be."

Falk has unearthed a new angle on this story. It is known that Dart "was critically mauled by the London establishment - notably the 'Piltdown Committee' who believed in the fake fossil" and that "he almost deserted palaeoanthropology". Nevertheless, he did continue to develop his hypothesis and submitted a paper to the Royal Society in 1929. This paper suggested that the cognitive capacity of Australopithecus was belied by its small brain. However, the paper was rejected (as Gee suggests: "presumably on the basis of reports by the Piltdown Committee").

Falk has, of course, a similar story to tell about Homo floresiensis, alias the Hobbit. Her role was to scan the cranium of the LB1 fossil and show its affinities are closest to Homo erectus. Papers are still being published suggesting that the Hobbit is not a separate species but the bones are from deformed humans.

"Almost every time someone claims to have found a new species of hominin, someone else refutes it. The species is said to be either a member of Homo sapiens, but pathological, or an ape. Brickbats of the first kind were levelled recently at H. floresiensis - that it wasn't a genuine species, but a modern human suffering from one of several kinds of microcephaly or from cretinism. But they had also been aimed at Neanderthal Man, discovered back in 1856, and thought by some to be the remains of a Mongolian Cossack from the Napoleonic wars."

Thus, to grasp the meaning of fossils, particularly human fossils, we need not just to have an appreciation of technical issues, but also an understanding of the cultural, social and ideological contexts for the reporting.

Craniums with clout
Henry Gee
Nature, 478, 34 (06 October 2011) | doi:10.1038/478034a

Abstract: A look at two early human fossils reveals the prejudices in ideas about human evolution, finds Henry Gee.

Book reviewed:
The Fossil Chronicles: How Two Controversial Discoveries Changed Our View of Human Evolution, Dean Falk, University of California Press: 2011. 280 pp. ISBN: 9780520266704