Heat-Induced Sterility and Its Possible Bearing on Evolution

Abstract

The extinction of some of the major groups of vertebrates may have followed their inability to resolve the conflict between (1) high temp. requirements for bodily functioning efficient enough to meet competition, and (2) low temp. requirements of the testes for normal spermatogenesis. Various ways modem groups of animals have solved this problem are discussed as well as the possible acceleration due to heat of the mutation rate in the first animals to attempt a constant body temp.