Not Your Pilgrim's Turkey
As we get ready for a great traditional Thanksgiving feast, I often wonder if this meal is really what the pilgrims and Native Americans would have eaten. Most likely our traditions have nothing to do with what really went down. We cannot even be sure that the first Thanksgiving had a turkey, and even if they did, according to a new study, this main dish would be genetically different than the bird present at the first Thanksgiving.
"Ancient turkeys weren't your Butterball," said Rob Fleischer, head of the Smithsonian Conservation Biology Institute's Center for Conservation and Evolutionary Genetics. "We set out to compare the genetic diversity of the domestic turkeys we eat today with that of the ancestral wild turkey from South Mexico. Some of what we found surprised us." First to note is that all commercial turkey lines have descended from the South Mexican turkey that was first domesticated in 800 BC.
To obtain the turkeys' genetic code, researchers sequenced the genomes of domestic turkeys from seven commercial lines and compared the genomes to those of three museum specimens of the South Mexican turkeys collected in 1899 from Chihuahua, Mexico.
What researchers found was that the domestic turkey exhibits less genetic variation than not only its ancestral wild counterparts, but the species has less diversity compared to other livestock breeds, like domestic pigs or chickens.
"It is often the case that selection in domestication reduces the level of variation," Fleischer said. "What did surprise us, however, is how well the ancient DNA from the three museum specimens worked to generate the genome sequences needed to determine the genetic variation and structure. These data and this approach show great promise for determining what genes were involved in the process of turkey domestication."
Turkey is the second largest contributor of poultry meat consumed worldwide and the production per bird doubled between 1970 and 2008 as breeders started selecting traits that would appeal to consumers. However, this genetic "improvement" of farm animals has resulted in a loss of genetic diversity.
The research is important in order to discover the differences between ancient and modern domesticated turkeys, which can predict any unforeseen problems that may threaten the stability of the commercial turkey lines.
According to the U.S. Department of Agriculture, Americans consume more than 45 million turkeys every Thanksgiving. So gobble up and enjoy your turkey day!
See more at the Smithsonian Conservation Biology Institute.
Read the complete study at Biomedcentral.com.
Turkey image via Shutterstock.