Zhang Receives Grant from National Science Foundation

Understanding the rules of honest signaling »

Dr. Yufeng Zhang, assistant professor in the College of Health Sciences, was recently awarded $504,545 from the National Science Foundation (NSF) for his project, “Collaborative Research: Understanding the rules of honest signaling.” Collaborators include Dr. Geoffrey Hill from Auburn University and Dr. Matthew Toomey from University of Tulsa. $1.4M was awarded for the entire project.

Why are birds so colorful? Why do small birds, subject to predation, put colorful and conspicuous pigments in their feathers? Such consideration of ornamental plumage coloration begins with the fundamental question that Darwin and Wallace pondered for decades. Pioneer works in avian mate choice and color production had found that female birds are much more likely to choose more colorful (or redder) males as mates. Interestingly, color pigments (mainly carotenoid) cannot be synthesized by birds or other vertebrates; they have to be ingested and moved to the tissue to be pigmented. Most birds eat only yellow pigments and to produce red pigments they have to modify ingested carotenoids from yellow to red. The complexities of this signaling system make it a fascinating focus for study. It is far from obvious why the hue of feathers reveals the individual quality or what prevents low-quality birds from cheating this system. Previous study conducted by the Zhang lab indicated that the molecular bioconversion of yellow to red carotenoids signal the function of mitochondria in males birds. Consequently, female birds are choosing mates with better mitochondrial function by judging on their plumage coloration. Mitochondria, which are commonly known as the “powerhouse” of the cell, consume oxygen and produce majority of the adenosine triphosphate (ATP: the energy currency for biological system) in cells. Linking the ornamentation used in mate choice to function of core respiratory processes provides a novel mechanistic explanation for why carotenoid coloration relates to a range of aspects of individual performance and why females use plumage redness as a key criterion in choosing mates.

For this project, NSF is funding $1.4 million dollars to a team of scientists with expertise spanning across animal physiology, cell biology, and genomics. Within this collaborative research, the Zhang Lab at the University of Memphis was awarded to study the relationship between plumage coloration and the core respiratory processes in birds. The Zhang lab will use whole animals, cell culture and isolated subcellular organelles to study the molecular and biochemical mechanisms of coloration, and will examine and compare these processes in House Finches in good or poor condition to deduce the specific mechanisms that promote or inhibit the production and accumulation of red pigments and hence, control plumage coloration. Understanding the biochemical and cellular rules that govern carotenoid coloration in songbirds is important not just for a better understanding of this central process in nature but because carotenoid pigments play a key role in cellular homeostasis in humans. Zhang and his team will share these insights and support STEM education through an ornithology summer camp program, curricula development and training workshops for public school teachers, and middle and high school student visits to investigator laboratories.

For more information on this award or research, contact Zhang at yzhang24@memphis.edu.