The relationship of blood oxygen affinity to body size in lizards

Abstract

1. 1. Oxygen affinity of whole blood of 51 species of lizards from 12 families was measured at the eccritic temperature of each species. 2. 2. Blood oxygen affinity was lower than that of birds or mammals and increased with increasing body size. 3. 3. Iguanid lizards were used as a basis for comparisons of other families. Blood oxygen affinity of lizards in the families Agamidae, Cordylidae, Lacertidae and Varanidae did not differ from that of iguanids of comparable body size. 4. 4. Teiid and anguid lizards had lower oxygen affinities than iguanids. possibly reflecting their more active lives. 5. 5. Scincid and chamaeleonid lizards had higher blood oxygen affinities than iguanids, apparently as a result of their lower eccritic temperatures. 6. 6. Geckonid and xantusiid lizards had higher blood oxygen affinities than iguanids at their normally low eccritic temperatures and at higher temperatures comparable to eccritic temperatures of iguanid lizards.