Birds of a feather are bred together: domesticated turkeys in prehistoric SW US
Lovely Lady Turkey at Farm Sanctuary by CETFA on Flickr
Turkeys have long been an important foodstuff in many parts of the world. In the U.S., not only has our post-colonial society been fueled by this fowl; historically, turkey meat, feathers, and bones have provided important uses for pre-contact Native Americans. But where did these birds come from? By examining the remains of turkeys from archaeological sites in the southwestern United States (circa 200 BCE – 800 CE), a group of scientists, led by Camilla Speller of Simon Fraser University, has shed some light on the matter. To do this, Speller’s group analyzed mitochondrial DNA from 149 turkey bones and 29 coprolites (fossilized dung) from 38 archaeological sites around the Southwest. Their recent findings can be found in the latest issue of PNAS.
In the past, many people believed that turkeys had already been domesticated in Mexico before being introduced to the southwestern United States. However, recent evidence suggests that domestication of the birds occurred in the US, either in the eastern region or in the Southwest itself. To confuse matters further, domesticated turkeys from Mexico were brought to Europe in the 1500s, spread throughout the continent, and reintroduced to America roughly two centuries later.
When the scientists from Simon Fraser compared mtDNA from the historic turkeys to that from modern American turkey populations, they discovered that Mexican turkeys and the Southwest turkeys looked very different. Not only did the groups show distinct genetic markers; information from the ancient US turkeys was extremely homogeneous — a mark of “breeding isolation”, in this case, lasting more than 1000 years. Evidence of turkey husbandry — pens, eggshells, remains, etc., further suggest long-term domestication localized in the southwestern United States.
Speller et al.’s findings help demonstrate that turkey domestication did, in fact, occur in the prehistoric Southwest. But where did the southwest domesticated turkeys originate in the first place? According to Speller’s group, they’re most likely the progeny of South Mexican Wild Turkeys or of the Rio Grande/Eastern Wild Turkeys, introduced to the southwest U.S. region as domesticates. But, for now, the answer remains a mystery. It will be the task of future studies to finally crack that egg wide open.
[via the New York Times]
Speller, C., Kemp, B., Wyatt, S., Monroe, C., Lipe, W., Arndt, U., & Yang, D. (2010). Ancient mitochondrial DNA analysis reveals complexity of indigenous North American turkey domestication Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0909724107
