Sunday, May 17, 2009


A May 16 New York Times article and a May 15 Wall Street Journal article reported on the discovery of fossilized remains from a “primate-lemur,” living 47 million years ago during the Eocene period.

Researchers believe it’s a candidate for placement in the human ancestral line. Although the fossil is lemur-like in most ways, it lacks several key features that monkeys, apes, and humans also lack--like a “tooth comb” (a tooth for fur-grooming) and a grooming claw.

During the Eocene period, there were two ape-like groups—tarsidae (ancestors of the tarsier) and adapidae (ancestors of the lemur). We’re not sure which of these groups gave rise to monkeys, apes, and humans. This discovery lends support to the less-popular belief that our ancestors were adapidae, rather than tarsidae.

The fossil, found in the Messel Shale Pit in Germany, is incredibly well-preserved: its stomach contained an identifiable meal (of fruit and leaves), and it was possible to see impressions of fur and soft body tissue.

That site has been the source of other well-preserved fossils, and made me wonder about the environmental conditions that make preservation possible. How rare are they? How many remains have we likely lost due to poor conditions for fossilization? I imagine we might have an entirely different picture of human history right now if our pattern of fossil discovery had been different.

The fossil is quickly becoming a star of the evolutionary world: it’s getting news conferences, a History Channel feature, a display at the American Museum of Natural History, and a book. This made me think about the economics of fossil-discovery, and the hype surrounding such a popular scientific topic. As Dawkins points out in “The Blind Watchmaker,” people are attracted to evolution (rather than, say, quantum mechanics) maybe because it appears so simple and accessible. To what degree is that accessibility exploited in the hype surrounding new fossil discoveries?


No comments: