A few days ago we saw Ida fall from her overhyped status as an ancestor of humans. Now some scientists are claiming that Archaeopteryx should lose its status as an ancestor of modern birds. Calling Archaeopteryx an icon of evolution, the Wall Street Journal (WSJ) borrows a term from Jonathan Wells while reporting that [t]he feathered creature called archaeopteryx, easily the world's most famous fossil remains, had been considered the first bird since Charles Darwin's day. When researchers put its celebrity bones under the microscope recently, though, they discovered that this icon of evolution might not have been a bird at all.
According to the new research, inferences about growth rates made from studies of Archaeopteryxs ancient fossilized bones show it developed much more slowly than modern birds. While the WSJ is reporting these doubts about Archaeopteryxs ancestral status as if they were something new, those who follow the intelligent design movement know that such skepticism has been around for quite some time. In his 2000 book Icons of Evolution, Jonathan Wells discussed differences between Archaeopteryx and modern birds and the implications for Archaeopteryx's place as an alleged link between dinosaurs and birds:
But there are too many structural differences between Archaeopteryx and modern birds for the latter to be descendants of the former. In 1985, University of Kansas paleontologist Larry Martin wrote: Archaopteryx is not ancestral of any group of modern birds. Instead it is the earliest known member of a totally extinct group of birds." And in 1996 paleontologist Mark Norell, of the American Museum of Natural History in New York, called Archaeopteryx a very important fossil, but added that most paleontologists now believe it is not a direct ancestor of modern birds.
(Jonathan Wells, Icons of Evolution, p. 116 (Regnery, 2000).)Archaeopteryx isnt the only evolutionary icon losing its claim as the ancestor of birds. In recent months weve seen paleontologists increasingly arguing that the entire clade of dinosaurs should no longer be considered ancestral to birds. As the WSJ article states:
There are lingering doubts that birds today are descendants of dinosaurs. Researchers at Oregon State University recently argued that the distinctive anatomy that gives birds the lung capacity needed for flight means it is unlikely that birds descended from dinosaurs like archaeopteryx and its kin. Their findings were published in June in the Journal of Morphology.As paleontologist John Ruben of Oregon State was quoted saying when his article was published:
But old theories die hard, Ruben said, especially when it comes to some of the most distinctive and romanticized animal species in world history.
"Frankly, there's a lot of museum politics involved in this, a lot of careers committed to a particular point of view even if new scientific evidence raises questions," Ruben said. In some museum displays, he said, the birds-descended-from-dinosaurs evolutionary theory has been portrayed as a largely accepted fact, with an asterisk pointing out in small type that "some scientists disagree."
"Our work at OSU used to be pretty much the only asterisk they were talking about," Ruben said. "But now there are more asterisks all the time. That's part of the process of science."
("Discovery Raises New Doubts About Dinosaur-bird Links," ScienceDaily, June 9, 2009.)While "museum politics" seem to dominate now more than ever when it comes to evolution, it's nice to at least see some of those asterisks getting a little attention in a major media outlet like Wall Street Journal.