25 November 2004

Dining on Dinosaurs?

Today is Thanksgiving Day in the United States. Many families will be feasting together, and most of them will have turkey for their holiday dinner.

Why is this bird called a "turkey", at least in the U.S., since it originally came from Mexico? Well, it made a round trip (return journey). Brought to Spain and the Mediterranean shortly after Columbus's voyage to the Western Hemisphere, it was carried to various parts of Europe by traders, including Levantine traders who handled goods from the East. In Britain it came to be known as Turkey fowl. In other European languages it is connected with India. British colonists brought it to America again. They also encountered similar wild fowl in Eastern North America. Here is the story of the name.

Turkeys are the only mainstream agricultural animal that was domesticated in the Americas . There are many domesticated plants from the Americas which have spread around the world (maize, potato, sweet "potato", rubber, lima bean, tomato, chili pepper, peanut, bottle gourd, sunflower, quinoa, cranberry, cotton, pineapple, papaya, avocado, tobacco, cassava (manioc), cacao, vanilla, cashew, pecan, Brazilnut, coca and others—about one-third of world crops were domesticated by native Americans).

But few widespread domestic animals come from the New World. The turkey is probably the only one you are intimately familiar with, and the only one that makes a significant contribution to modern agriculture. Llamas, alpacas, guinea pigs, American bison (buffalo), the muscovy duck and some others (e.g. capybaras—not really domesticated) are used for food or work, but are not much raised outside their original homes. Dogs were raised in the Americas before Columbus, but they probably accompanied human settlement of the Americas from Asia.

Current scientific thinking is that birds descended from dinosaurs. They are placed in the group of maniraptoran dinosaurs, those with "seizing hands."

Although new fossil finds continue to add to our understanding of evolution of birds, and may change our ideas substantially if something really revolutionary turns up, the basic thesis is well supported by a growing number of fossil feathered dinosaurs.

There are some, of course, who see evidence that birds are not related to dinosaurs. This is definitely a minority view, and hinges on disputed technical details.

There is always ambiguity in science, but even with uncertainty there can be consensus. The consensus is that when you carve that Thanksgiving turkey you will be dining on a dinosaur! Bon appetit!

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