Radio Script
1998

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Musk Ox Kin
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STORY: Few animals better symbolize the Arctic than the musk ox. Short and stocky, musk ox have a hump in their shoulder, a sloping rump, and long shaggy brown hair that drapes to the ground. They live only in Greenland, Canada, and Alaska, where populations were reintroduced after they were hunted to near extinction a century ago.

But this story begins not in Alaska or Greenland, but in China. There, high in the densely forested mountains, lives a sheep-like animal called the Takin. Scientists since the 1850s have believed that musk ox and Takins are closely related. That's because the two species look alike and both are known for their instinct to form a circle of defense against predators.

Pam Groves has studied the Takin and the musk ox, and says looks are often deceiving. Groves is a geneticist at the University of Alaska Fairbanks. She used a technique called gene sequencing to compare mutations in their DNA. The method is used to determine relationships among species and to understand how species evolved.

GROVES: "I started out this research assuming, because this is what I'd been told, that the Takin and the musk ox were close relatives. And there definitely are similarities between them in body size and shape and a lot of behavioral similarities. But when I actually compared the DNA, I found that the Takins were actually more closely related to assorted sheep, the Dall sheep that we have here in Alaska and bighorn sheep, as well as domestic sheep. Whereas the musk ox is actually more closely related to some species that live in Asia, some small goat species, and possibly the mountain goat."

According to Pam Groves, musk ox are actually more closely related to the Goral, a small goat that lives in Asia--which incidentally doesn't look anything like a musk ox.

GROVES: "I collected more and more data thinking that maybe I'd just not done it right or if I collected more and more information it would tell me the opposite. But after a couple of years collecting more and more DNA sequences I became convinced that what I had was what it showed to be and it did make me step back and reevaluate how I'd been looking at the big picture."

Pam Groves, of course, has changed the big picture. When she debunked the notion that Takin were a close relative of the musk ox, she'd unwittingly discovered something even more perplexing. How could two species that look and behave so much alike NOT be related?

GROVES: "What I've decided, after a lot of deliberation, is that these behaviors are actually the result of what is called convergent evolution, or evolutionary forces of natural selection pushing the animals to develop these similar behaviors in their different environments."

Early explorers gave the musk ox its name because they thought it looked like a musky smelling ox. Thanks to Pam Groves, we now know the musk ox is more goat than ox.

OUTRO: For Arctic Science Journeys, this is Doug Schneider, reporting from Fairbanks, Alaska.