Evolution
From Epicurus Wiki
Epicurus and, at great length, Lucretius anticipate some key features of Darwinian evolution (e.g., heritability of phenotypes, the concept of "fitness" and natural selection) but not others (mutation, speciation, and the historic tendency for organisms at large to accumulate complexity). In the Epicurean tradition, the first living things on earth arose fully-formed by the chance assemblage of atoms. Many such organisms were unviable and died off quickly; only the creatures that were sufficiently well-constituted for survival were able to propagate their kind down to the present day.
NOTE: It would also be salient to describe here in some detail how Lucretius' account of the function of organs (e.g., "Do not think that the ear was made to hear with") is at odds with the modern school of evolutionary biology, which maintains the "argument from design" (c.f. Dawkins, The Blind Watchmaker); this conflict in approach to functionalism has an old history. The physician Galen took later Epicureans to task to explain how certain sophisticated attributes of anatomy could have arisen by chance. Another challenge that needs to be addressed is found in Cicero's De Natura Deorum: if humans could spring forth from the earth by chance assembly of atoms, why not more simple things like columns or even entire buildings? - Erik
While Lucretius' own account of natural history in De Rerum Natura is laden with Roman folklore (as is understandable), it also suggests the evolution of living things on earth. Lucretius is particularly astute in his observations of how specifically the human species evolved up to his time. Sprinkled with remarks on family-structure, the development of political institutions, and anthropology, Lucretius' "speculative evolution" is basically true: the transition from hunter-gatherer to cave-dweller, the gradual sophistication of courtship and mating, the "softening" of human nature by more lasting sexual attachments and more systematic child-rearing, the evolution of the brain-power that enabled humans to grasp basic precepts of reciprocal self-interest, which in turn engendered the underpinnings of social structures, all these processes are presented as evolutionary, as stages in the historic tendency for at least humans to accumulate (in this case, mental) complexity.
