A comparison of the population ecology of 4 Cryptomys hottentotus subspecies.

This article examines the population demographics, colony size, and body mass variation among four subspecies of the African mole-rat *Cryptomys hottentotus*—the Mahali mole-rat (*C. h. mahali*), highveld mole-rat (*C. h. pretoriae*), Natal mole-rat (*C. h. natalensis*), and common mole-rat (*C. h. hottentotus*)—in relation to their distinct microclimates and evolutionary history across South Africa. The study supports the hypothesis that all ancestral *C. hottentotus* subspecies were arid-adapted with large colonies, as seen in the Mahali mole-rat, but subsequent dispersal into habitats with varying aridity and temperature led to selection for different colony sizes that confer adaptive fitness benefits, including thermoregulatory advantages via huddling in cooler environments. Notably, the Mahali mole-rat retained the largest colonies in warm, arid habitats, while the Natal mole-rat, inhabiting hyper-mesic montane areas, also evolved relatively large colonies likely to offset thermoregulatory costs. Conversely, the common and highveld mole-rats, occupying warmer mesic environments, exhibited smaller colony sizes. Additionally, body mass variation inversely correlated with colony size, with subspecies forming larger colonies tending to have lower individual body mass, reflecting energetic adaptations to their environments.