TEMPERATURE REGULATION IN HYRAX

1. 1. Th hyrax are medium-sized African mammals (2-3 kg) which look like large rodents but possess taxonomic affinities with the elephant. Their behavior suggest that basking in the sun plays an important role in the regulation of their body temperature. 2. 2. We found that in the laboratory four different species of hyrax maintained their rectal temperature within the normal mammalian range at air temperatures between 4 and 40°C. 3. 3. In the cold hyrax increased their oxygen consumption, and in the heat they panted, salivated and groomed. 4. 4. Thus they do possess the usual physiological mechanisms for regulating their temperature, but we do not rule out the possibility that in nature they exhibit a nightly hypothermia and bask in the sun to warm. © 1969.