Student Researchers Analyze Effects of Exercise, Environment on Mice

Research Mouse

Mercer student researchers are working with Associate Professor of Biology Dr. Craig Byron to analyze the effects of a specific type of exercise within certain habitat types on the muscles and bones of mice. The data should provide insight into primate evolution by highlighting anatomical variation related to climbing.

On this particular project, Dr. Byron has worked with more than 20 undergraduate researchers since 2008. The objective of his research is to study the effects of grasping and fine branch locomotion on forelimb and hindlimb size and shape in small mammals. “Laboratory mice are raised within experimental habitats that  require mice to use acrobatic and agile climbing postures and limb positions,” Dr. Byron said. “In the climbing habitats mice develop unique morphologies within skeletal, muscular, and nervous tissues related to facultative grasping with the foot and coordinated tail use. These morphologies enhance an organism’s ability to balance and walk on top of narrow branches.”

Research MouseDr. Byron’s interest in these experiments is to understand the role of the opposable hallux (big toe) and tail use as they impacted the earliest evolutionary stages of primate arboreality (living in trees). To model these tiny-sized mammals from roughly 55-65 million years ago, standard laboratory mice are used. This is because they are similar in size to fossil primates who initially lacked specialized anatomy for climbing. Results suggest that the basic mammalian bodyplan in tiny-sized organisms includes a foot and tail module where the development and evolution of skeletal, muscular, and central nervous system tissues are integrated.

As of now, three primary research articles have been published — and two more are in review — that include undergraduate co-authors. Students participating in the project learn techniques that are helpful for careers in biomedical science such as microdissection, histology, morphometry, and statistical analysis.

View a full gallery of the research project.