Ancient DNA offers clues to how barnyard chickens came to be. National Evolutionary Synthesis Center, April 21, 2014. Ancient DNA adds a twist to the story of how barnyard chickens came to be, finds a study in the journal PNAS. Analyzing DNA from the bones of chickens that lived 200-2300 years ago in Europe, researchers report that some of the traits we associate with modern domestic chickens — such as their yellowish skin — only became widespread in the last 500 years, much more recently than previously thought. Picked up by Ars Technica, Nature and Public Radio International.