We will be comparing the light meat and dark meat of different avian species with a protein gel electrophoresis. The chicken and turkey both have very light breast meat and darker leg meat so we expect to see similarities between them. Due to their differences in lifestyle (migration, duration of flight, leg strength) of the chicken/turkey and the duck, the duck's breast and leg meat are much darker. The duck will share fewer similarities to the breast meat in the other birds, and will appear more closely related to the leg of the chicken and turkey.
This color phenomenon arises due to the type of muscle fiber. Slow twitch muscle fibers have a slower contraction, a higher concentration of myoglobin, and are redder/darker in color. The myoglobin is the primary oxygen carrying pigment in the muscle cell. Since slow twitch muscles are usually found in animals with more endurance needs (like the duck) they will need more oxygen and have a higher concentration of myoglobin. The fast twitch muscle cells do not need as much oxygen since they are not used as long as the slow twitch, and are generally used in quick bursts. They do not benefit from the extra myoglobin and appear lighter as a result.
Zierath, Juleen R., and John A. Hawley. "Skeletal Muscle Fiber Type: Influence on Contractile and Metabolic Properties." PLoS Biology. Public Library of Science, Oct. 2004. Web. 10 Feb. 2017. <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC521732/>.
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