Lifespan and reproductive aging in captive Northern tree shrews (Tupaia belangeri)

Tree shrews are small mammals closely related to primates, which originate in Southeast Asia. In several aspects of their morphology and physiology, tree shrews more closely resemble humans than rodents. For example, the development of their visual system parallels that of humans, making them a desirable model species for pre-clinical research. Despite the use of tree shrews in research for over 50 years, little is known about the basic demography of tree shrews. No detailed lifespan studies are available for tree shrews, and it is unclear if females and males experience aging similarly. This information is needed given the increased use of tree shrews in research to ensure the proper selection of age groups. Here, we utilize the existing records of the T. belangeri (Northern tree shrew) colony at the University of Alabama at Birmingham to investigate how age impacts the reproductive success of individuals and examine sex differences in lifespan. We find that at the UAB breeding colony, T. belangeri males have an increased median lifespan compared to females, but detect no differences in maximum lifespan (90% survival) and mortality. Furthermore, there is little evidence of reproductive aging in general, but having two older parents slightly decreases reproductive output.