Hormones in mammalian evolution.
Animals that produced increased levels of prolactin and dehydroepiandrosterone (DHEA) survived the period of mass extinctions at the end of the Cretaceous period. DHEA increases thermogenesis and supported existence through the extended episode of cold and dark. Further increases in DHEA and prolactin produced continual physiological and anatomical changes which eventually produced all of the characteristics of mammals.
Howard
J
J
D000818:Animals; D005075:Biological Evolution; D006728:Hormones / Q000502:physiology*; D008322:Mammals / Q000502:physiology*
D006728:Hormones