Lovecraft and Lamarck

HPl was a devout evolutionist, but he was far from a darwinian. His stories from "The Beast In the Cave", through Dagon and the Innsmouth look to his final stories all show that he was influenced by Ernst Haekel.

However, he seemed to be a Lamrakian. He believed that traits and characteristics can de-evolve people to their lowest and apish mannerisms. Therefore, they could also devolve to saurians, amphibians, penguins, or cephalopods.

50 years before Darwin, Jean Baptiste-Lamark believed that organisms evolve because they try to. The environment changes the animal by "inheritance of acquired characteristics.".

Therefore, if you cut off all mice tails, they will evolve to tailless mice. In HPL's world, put a man in a cave and he and his descendents become pale, blind, and insane. This quickly leads to racism and thus why social darwinism was condemned.

Darwin, by the way, believed that because there is wide variation in animal species and as environmental stresses begin to eradicate non-conforming animals, new animals will "evolve" to claim the modified environment.

Epigentics, however, has picked up traces of lamark. Diet, behavior, and environmental changes can pass on not just genetic changes, but acquired characteristics. Not losing tails, but things like tool building, problem solving, and exploitive tactics.

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Some of this is extracted from Jessica Ruvinsky, "Lamark's Last Laugh", Discover, Nov. 2006, p. 37.