Bruce Smith, senior scientist at the Smithsonian's National Museum of Natural History, said just like most Americans came from somewhere else, so did most of the traditional foods of Thanksgiving.
"We can trace many of these foods up through the southwestern United States into other parts of the country," Smith said in a statement. "Most likely this diffusion happened as a result of trading or other contact among American Indian tribes in this country."
Smith said some facts about the origins of the Thanksgiving holiday menu include:
-- The turkey was domesticated twice, in central Mexico and in the southwestern United States. This domestication happened at the same time about 2,000 years ago. However, southwestern domesticate disappeared, and the turkeys eaten today are derived from the Mexican domesticate.
-- Potatoes were domesticated in South America, most likely Peru, about 10,000 years ago.
-- There are many species of squash and pumpkins grown today in the United States, but the most common species was domesticated twice -- in Mexico and the eastern United States.
-- The orange-skinned "pumpkin" lineage of the squash was the first plant to be domesticated in the Americas, about 10,000 years ago in Mexico.
-- Corn was domesticated in Mexico more than 8,000 years ago.
-- Cranberries are native to the United States, most likely the New England area.