Professor Matthew Pamenter and Postdoctoral Fellow Daniel Munro from the University of Ottawa, with Professors Nigel Bennett (University of Pretoria, South Africa); Bill Milsom (University of British Columbia) and Ken Storey (Carleton University)
Department of Biology
Among the only mammals able to sustain life in low-oxygen environments (i.e. hypoxia), African mole rats show clear signs of adaptation to such extreme conditions; however, the evolutionary origin of these adaptations remains a mystery.
Most mammals require a continuous source of oxygen in order to survive and to produce enough energy for everyday tasks, but they are often exposed to environments with limited oxygen levels. When introduced into such situations, most vertebrates will hyperventilate in a largely futile attempt to bring more oxygen to their tissues. However, not naked mole rats! They have mastered the ability to match metabolic demand to energy supply by drastically reducing their metabolic rate in hypoxia, allowing them to thrive in areas that most mammals cannot. To gain a better understanding of the evolutionary origins of hypoxia-related adaptations in these fascinating creatures, Prof. Matthew Pamenter led an international collaboration funded by the National Geographic Society to South Africa with partners from the University of Pretoria in South Africa, the University of British Columbia, Carleton University, and McMaster University.
Within this partnership, they explored the metabolic, ventilatory and thermal responses that the mole rats employ to tolerate hypoxia in hopes of better understanding the mechanisms that enable this tolerance. Overall, they studied eight species of African mole rats, obtaining whole animal and mitochondrial physiological data, as well as collecting many samples for post-trip analysis in the labs of Profs. Pamenter and Storey. They plan to compare the results they have collected across species in order to determine if hypoxia-tolerance is due to adaptive evolution - dependent on environmental factors, or if it is an evolutionarily conserved trait – remaining relatively unchanged far back in history. As Prof. Pamenter says: “understanding how nature has “solved” the problem of physiologically tolerating low oxygen environments may offer important insight into many hypoxia-related pathologies, including chronic pulmonary disorders, heart attack and stroke, anemia, etc.”