Golden brown, snow white, jet black, or speckled: Anyone walking through a chicken coop is amazed by the variety of plumage colors. But why do chickens look so different? A new international study, in which the University of Leipzig played a key role, provides the answer: a single gene plays a decisive role.
The study focuses on a molecule called MC1R. It acts like a switch in the skin cells, controlling the formation of color pigments. Depending on how active this switch is, more dark or more light color pigments are produced.
The gene that contains the blueprint for MC1R has changed significantly in domestic chickens since they were domesticated by humans thousands of years ago. The study began with a genomic analysis conducted by Uppsala University in Sweden, which examined the genetic material of more than 10,000 chickens. During this analysis, MC1R stood out as a particularly variable section of the genome.
From the Chicken Coop to Evolutionary Research
Apparently, human breeding has contributed to the accumulation of a particularly large number of variants of this gene in domestic chickens. This demonstrates how quickly new traits can develop when humans breed animals over many generations. The researchers thus provide a vivid example of a fundamental principle of evolution.
In practical terms, this could mean that color traits in animal breeding will be easier to predict in the future. The scientists also plan to investigate whether similar patterns occur in other vertebrates, in order to perhaps solve even more of nature’s color mysteries.
Original publication:
C. Ma, A. Liebing, G. Kleinau, A. Kamprad, L. Calabrese, M. Szczepek, Z. Li, M. Larsson, P. Scheerer, C. Stäubert, & L. Andersson, Ultrarapid MC1R protein and associated plumage color evolution in the domestic chicken, Proc. Natl. Acad. Sci. U.S.A. 123 (24) e2605288123
