FORT LAUDERDALE, FLORIDA--They said it couldn't be done. But a team at the University of Alabama just may have succeeded in extracting some DNA from a dinosaur. And guess what it resembles: a turkey. If the work pans out, the scientists say, it will be the "first direct genetic evidence to indicate that birds represent the closest living relatives of the dinosaurs."
At the Florida Symposium on Dinosaur Bird Evolution, held here last week, biologist William Garstka of the University of Alabama in Huntsville reported that--with expertise from NASA and scientists from the Russian Academy of Sciences who have been probing for DNA in permafrost--he and colleagues may have isolated a stretch of mitochondrial DNA from 65-million-year-old Triceratops bones found in North Dakota.
Because the bones were poorly mineralized, he says, the researchers think they were able to get a 130-base pair sequence from two vertebrae and a rib fragment. Matching the sequence against DNA samples from 28 animals, including 13 bird species, they found that it made a 100% match with the turkey and at least a 94.5% match with other birds. Naturally, says Garstka, "we thought of turkey sandwiches" that had probably been consumed both in the lab and in the field. But when the team checked for turkey DNA in turtle bones, dirt, and burlap from the same site, none tested positive.
DNA from dinos is "for most people a truly heretical idea," Garstka says, because many experts believe nucleic acid is unlikely to survive more than 100,000 years. Zoologist John Ruben of Oregon State University in Corvallis says, "The fact that turkey DNA was so similar to that of Triceratops was very suspicious." Garstka himself says that "at this point, I remain quite skeptical of our own work. We would expect this kind of result from a theropod [a birdlike dinosaur], but here we're talking Triceratops."