A Darwinian Demon is a hypothetical organism which can maximize all aspects of fitness simultaneously and would exist if the evolution of species was entirely unconstrained. It is named for Charles Darwin. Such organisms would reproduce directly after being born, produce infinitely many offspring, and live indefinitely. Even though no such organisms exist, biologists use Darwinian Demons in thought experiments to understand different life history strategies among different organisms.
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Darwinian Demon Wikipedia(Text) CC BY-SA