Jonathan Wells by Icons of Evolution

Author:Icons of Evolution [Evolution, Icons of]
Language: deu
Format: epub
Published: 2010-03-20T13:18:17+00:00

Archaeopteryx: The Missing Link • 129

FIGURE 6-4 Feathered Bambiraptor.

Recomstructed animal displayed at the April 2000 Florida Symposium

on Dinosaur Bird Evolution showing "conceptual integumentary

structures."

130 • ICONS OF EVOLUTION

There were several outspoken critics of the dino-bird theory at

the Florida symposium. One was University of North Carolina

ornithologist Alan Feduccia, who has predicted that the dino-

bird theory will turn out to be «the greatest embarrassment of

paleontology of the 20th century.» Another was Larry Martin,

who has said that if he had to defend the dino-bird theory, «I'd

be embarrassed every time I had to get up and talk about it.»

And Storrs Olson ruffled some dino-feathers by passing out

buttons that proclaimed «Birds are NOT dinosaurs.»

But the dino-bird enthusiasts at the symposium outnumbered

their critics, and they were undeterred from dressing up

Bambiraptor in imaginary feathers. Not being a cladist myself,

I found this rather funny. As a molecular biologist, however, I

found something else even funnier.

Turkey DNA from Triceratops?

On the second day of the symposium, William Garstka reported

that he and a team of molecular biologists from Alabama had

extracted DNA from the fossil bones of a 65-million-year-old

dinosaur. Although evidence from other studies suggests that

DNA older than about a million years cannot yield any useful

sequence information, Garstka and his colleagues amplified and

sequenced the DNA, compared it with known DNA from other

animals, and found that it was most similar to bird DNA. They

concluded that they had found «the first direct genetic evidence

to indicate that birds represent the closest living relatives of the

dinosaurs.» Their conclusion was reported the following week

by Constance Holden in Science.

The details of the discovery, however, are revealing.

First, the dinosaur from which Garstka and his colleagues

allegedly recovered the DNA was a Triceratops. According to

paleontologists,

Archaeopteryx: The Missing Link • 131

there are two main branches in the dinosaur family tree. One

branch included the three-horned rhinoceros-like Triceratops

which millions of people have seen in museum exhibits and

movies. But birds are thought to have evolved from the other

branch. So according to evolutionary biologists, Triceratops

and modern birds are not closely related, their ancestors having

gone their separate ways almost 250 million years ago.

Even more revealing, however, was that the DNA Garstka

and his colleagues found was 100 percent identical to the

DNA of living turkeys. Not 99 percent, not 99.9 percent, but

100 percent. Not even DNA obtained from other birds is 100

percent identical to turkey DNA (the next closest match in their

study was 94.5 percent, with another species of bird). In other

words, the DNA that had supposedly been extracted from the

Triceratops bone was not just similar to turkey DNA—it was

turkey DNA. Garstka said he and his colleagues considered

the possibility that someone had been eating a turkey sandwich

nearby, but they were unable to confirm that.

At first, when Garstka presented his findings I thought it was

an April Fools joke—but it was already April 8. Then I looked

around to see whether anyone was laughing—but no one was,

at least not openly. When I returned home the next day and

told my wife the story, she said it reminded her of a child who

botches an attempt to stay home from school. When the child's

mother puts a thermometer

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