As has already been made clear, the theory of evolution claims that various imaginary life forms emerged from the seas and by way of incremental changes, became reptiles; and that birds then evolved from reptiles. According to the same scenario, reptiles are the forerunners not only of birds, but also of mammals. But the hypothesis that reptiles evolved into mammals has no scientific basis, as the fossil record shows. Despite all the excavations carried out to date, not a single intermediate form linking reptiles to mammals has ever been found. Nor can any such transitional form be discovered in the future, because no such life form ever existed. That is why the evolutionist Roger Lewin was forced to write that "The transition to the first mammal, ... is still an enigma." (Roger Lewin, "Bones of Mammals’ Ancestors Fleshed Out," Science, Volume 212, 26 June 1981, p. 1492)