Abstract
Marsupial (pouched) mammals have unusual biological traits that distinguish them from other mammals (e.g. our own placental group). One poorly understood trait is the highly variable presence/absence of a kneecap (patella) bone, which seems to be independently lost in the evolution of marsupial lineages, but the patterns and processes involved are unknown. We seek a motivated student interested in phenotypes, ontogeny, imaging and evolution to unravel this mystery and figure out how marsupial kneecaps evolved (rotation), and then test developmental, biomechanical, ecological and evolutionary hypotheses that explain how and why the patella had its peculiar evolutionary patterns.
References
- ASHER, R. J., HOROVITZ, I. & SANCHEZ-VILLAGRA, M. R. (2004). First combined cladistic analysis of marsupial mammal interrelationships. Mol Phylogenet Evol 33, 240-50.
- MIKIC, B., JOHNSON, T. L., CHHABRA, A. B., SCHALET, B. J., WONG, M. & HUNZIKER, E. B. (2000). Differential effects of embryonic immobilization on the development of fibrocartilaginous skeletal elements. Journal of Rehabilitation Research and Development 37, 127-133.
- REESE, S., PFUDERER, U. R., BRAGULLA, H., LOEFFLER, K. & BUDRAS, K. D. (2001). Topography, structure and function of the patella and the patelloid in marsupials. Anat Histol Embryol 30, 289-94.
- FOX, A. J., WANIVENHAUS, F. & RODEO, S. A. (2012). The basic science of the patella: structure, composition, and function. J Knee Surg 25, 127-41
- SAMUELS, M., REGNAULT, S. & HUTCHINSON, J.R. (2017). Evolution of the patellar sesamoid bone in mammals. PeerJ 5:e3103. doi: https://doi.org/10.7717/peerj.3103