11/24/2004
Brief Fossil Update
Our editor, Brian Trumbore, suggested that old Bortrum take the Thanksgiving week off. However, I feel compelled to follow up on the hobbit-like human fossil found on the island of Flores that I wrote about a couple of weeks ago. Remember that Australian and Indonesian researchers found a skull and other skeletal remains of an individual on the island and concluded that it was a new species of human. The fossil was only 18,000 years old. Until this find, we modern Homo sapiens were the only humans thought to exist at that time. A recurring theme is these columns is that any new and startling finding is almost certain to generate controversy. This finding is no exception.
The November 12 issue of Science contains a report by Michael Balter that a group of critics has arisen to challenge classifying the tiny 3-foot tall Flores human as a new species. For example, Maciej Heneberg, a paleopathologist at the University of Adelaide in Australia claims that the skull resembles a 4,000- year-old microcephalic skull of a modern human that was found on the island of Crete. An Indonesian paleoanthropologist, Teuku Jacob, has latched on to the skull and taken it to his lab at the Center for Anthropology in Jakarta. Jacob claims that the skull is just that of a small modern human.
In rebuttal, the finders of the fossil remains point to the fact that they’ve found the remains of at least 7 other humans with tiny bones on Flores. Other independent researchers back up the conclusion that a new species has been found, citing the shape and sizes of other features of the skeleton as showing it cannot be the remains of a modern human. Not being a paleo-anything, just a physical chemist, I’m not qualified to weigh in with an opinion on the matter. However, I do confess to hoping these researchers are right. I think it’s neat to think of 3-foot tall humans surviving while we modern guys and gals were strutting around thinking we were the only game in town.
Unfortunately, it’s such controversies that are seized upon by creationists to cast doubt on the whole concept of evolution. I was disheartened to find in the same issue of Science reports of actions last month by certain school boards in Pennsylvania and in Wisconsin that would include in the curriculum the teaching of alternatives to evolution, specifically so-called “intelligent design”.
A much older, exceptional skeleton has turned up in Spain, as reported in last week’s November 19 issue of Science in an article by Salvador Moya-Sola of the Institut de Paleontologia M. Crusafont in Barcelona and his coworkers. There seems to be no controversy about one thing. This is one truly monumental 12.5 to 13 million-year-old fossil. So often these old fossils consist of just a single part or two of the skeleton of the deceased. In this case, a substantially complete skull was found along with ribs, wrist, hands and vertebrae.
The Spanish researchers propose that this guy, he is a male, is probably close to being the last common ancestor to both humans and the great apes. The implication is that this fellow could walk upright, climb trees and probably walk on all fours on branches. However, the hands were small and not developed sufficiently to permit him to swing around in trees below the branches as great apes do today. The proposal is that later members of this evolutionary line developed bigger hands suited to swinging in trees and that somewhere along the line we humans branched off. We came down out of the trees and developed smaller hands as we lost the need to swing in the trees.
The same issue of Science contains an article by Elizabeth Culotta, who notes that, while other scientists may question the proposals of the Spanish workers, they all agree the fossil itself is a treasure. They are quoted as describing the fossil in terms such as “this skeleton is great”, “an amazing fossil” and “a marvelous find, a dream come true”. With all the attention, it seems likely that this fellow will eventually take his place along side Lucy and other famous fossils in the evolutionary scheme of things.
Well, I promise I’m finished with evolution for this year. Have a happy Thanksgiving and don’t eat too much of that bird that evolved either from or shared a common ancestor with the dinosaur!
Allen F. Bortrum
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