Detection and Comparison of Heavy Chain Myosin Isoforms Slow Type 1 and Fast Type 2 in Calf and Adult Baleen Whales
Authors:Haidi Ahmed, Ryan Bailey, Kristine Blando, Sofia Malvar
Mentor:Cori Newton, Biology Lecturer, California State University, Channel Islands
Unlike most terrestrial mammals which exhibit very limited breath-hold capabilities, diving marine mammals remain submerged for extended periods of times. Key adaptations have allowed these organisms to exploit this aquatic environment. Although the development of skeletal muscle adaptations has been explored in some marine mammals, very limited information is available regarding the ontogeny of mysticetes. Therefore, we are currently characterizing the muscle fiber type composition from stranded baleen whales of various developmental states. We find that baleen adults exhibit a significant decrease in fast twitch fibers compared to calves. Combined with previously document data which have revealed enhanced skeletal muscle myoglobin concentrations in adult baleen whales compared to calves suggests an increased reliance on anaerobic respiration in young whales.