Jean-Baptiste Lamarck

Jean Baptiste Lamarck was a French naturalist who proposed one of the first theories of evolution. He postulated that an animal was able to change a characteristic during its lifetime depending on its behaviour, and that these changes would be passed onto its offspring resulting in speciation. For instance, if a giraffe attempted to eat the leaves off the top of a tree it would be constantly stretching its neck, resulting in both a longer neck for itself and that this characteristic would be passed onto its young.

Lamarck's theory was fundamentally flawed in that it could not explain the contradictions in observations, for instance a neutered dog would not give birth to sterilised young. Further research into DNA demonstrated the mechanisms by which characteristics were passed on, invariably disproving the theory. As such it receives no support from mainstream science.