Integrative and comparative biology
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Integr. Comp. Biol. · Nov 2010
The heat dissipation limit theory and evolution of life histories in endotherms--time to dispose of the disposable soma theory?
A major factor influencing life-history strategies of endotherms is body size. Larger endotherms live longer, develop more slowly, breed later and less frequently, and have fewer offspring per attempt at breeding. The classical evolutionary explanation for this pattern is that smaller animals experience greater extrinsic mortality, which favors early reproduction at high intensity. ⋯ Because large animals are constrained by their capacity for heat dissipation, they have low reproductive rates. Consequently, only those large animals living in habitats with low extrinsic mortality could survive leading to the familiar patterns of life-history trade-offs and their links to extrinsic mortality rates. The HDL theory provides a novel mechanism underpinning the evolution of life history and ageing in endotherms, and makes a number of testable predictions that directly contrast with the predictions arising from the DST.