[Molecular aspects of high altitude respiration of birds. Hemoglobins of the striped goose (Anser indicus), the Andean goose, (Chloephaga melanoptera) and vulture (Gyps rueppellii)].

Respiration of birds at high altitude and the structural adaptation of avian hemoglobins are studied. Applying the method of the "minimal biological distance", hemoglobins of closely related species were sequenced and compared with each other. Physiological measurements and sequence data show that adaptation to hypoxic stress can be interpreted as exchange of one amino acid. The structural aspects of the genetical data are discussed on the basis of the atomic model of hemoglobin. High-altitude respiration is not a general characteristic of birds: the adaptation to high altitudes is the result of a specific mutation, thus distinguishing a species from its closest relatives in the lowland.