Contrary to popular belief, Neanderthals have been proved to be false. In Time magazine (from 1971) it was reported that the remains found of the supposed Neanderthal in France in 1903 were in fact of an actual modern human. What threw off the science was the assumption that the skeleton was "normal", so then assumed to be different than modern humans; but in fact, more recent (1971-today) studies have shown that the skeleton is of an average male but disfigured from arthritis and rickets. (Source: "Upgrading Neanderthal Man", Time Magazine, May 17, 1971, Vol. 97, No. 20) So the use of the Neanderthal in the movies are completely for laughs, not for actual facts.