Mississippi Department of Wildlife, Fisheries and Parks 1 article published in JoVE Environment Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid Eric S. Michel1,2, Emily B. Flinn1, Stephen Demarais1, Bronson K. Strickland1, Guiming Wang1, Chad M. Dacus3 1Department of Wildlife, Fisheries and Aquaculture, Mississippi State University, 2Department of Natural Resource Management, South Dakota State University, 3Mississippi Department of Wildlife, Fisheries and Parks Phenotypic differences among cervid populations may be related to population-level genetics or nutrition; discerning which is difficult in the wild. This protocol describes how we designed a controlled study where nutritional variation was eliminated. We found that phenotypic variation of male white-tailed deer was more limited by nutrition than genetics.