Adaptation for high-altitude respiration

Species Cardiac muscle (mg/g wet weight) Pectoral muscle (mg/g wet weight) 

Source Catlett, Walters Dutro (1978) Pages Planas (1983) Johansen et al. (1987) Saunders Fedde (1991). 

When the P,o for whole blood from a range of avian species is measured, the values obtained relate to the degree of hypoxia the birds normally encounter. Birds whose normal habitats are at high altitudes have the lowest P o (Table 6.5), for example (i) Riippell s griffon, living in Central Africa is known to 

Source Lutz, Longmluir Schmidt-Nielsen (1974) Isaacks et oL (1977) Petschow el al. (1977) Farad (1991) Jessen ct al. (1991). 

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