All this is patently absurd to the dean of American archaeologists, Herbert J. Spinden. If tools in the New World resemble the Aurignacian or the Solutrean, it is an accident—perhaps an accident of psychic unity. He is against all talk of paleolithic man in the Americas on the late edge of the Great Ice Age. In the face of facts presented by Russian and American glacialists, he maintains that “eastern Siberia was rather heavily glaciated.”[15] He believes that certain Asiatic peoples with a sudden urge for travel first appeared at the Siberian-Alaskan portal about 2500 B.C.[16] They could not have been men of the Old Stone Age because, he asserts, we have found nothing in Siberia that approaches the paleolithic; indeed, we have found no paleolithic tools north of 54° in England, of 53° in Siberia, or of 43° on the Sea of Japan, while “the portal to America for man and beast lies at 67° north latitude.” We have, then, “a no-proof barrier zone a thousand miles deep extending clear across the Old World.”[17] This “rules out invasion of America until relatively modern times because it shows that a wide zone of the Old World, blocking the road to America, was itself unused by man until long after the last continental ice sheet ... had disappeared.”[18] Obviously, Spinden’s argument is not based on evidence in the Americas, but rather on lack of evidence in little studied Siberia. He ignores the presence of paleolithic tools in northern Manchuria together with the fossils of extinct mammals.[19] He concedes that even in the regions of “the most ancient civilization” in the Old World there is no trace of such high technical skill in flint chipping as the Folsom “before the fourth millennium before Christ.” But—appearing to ignore the geological evidence connected with Sandia, Folsom, Clovis, Abilene, and Lake Mohave—he interprets this as meaning that man cannot have reached the Southwest before the golden age of Ur. He speaks of “the lost cause of paleolithic man in America.” He accepts Solutrean flint work as paleolithic, but not Folsom or Eden. “Now, even if we admit that Folsom man hunted the mammoth, we must place that sporting event not earlier than 2000 B.C.”[20] Was the First Migration Interglacial? As we think we have shown in Chapter 8, we can never hope to date early man at all exactly by means of elephants or bison or any other extinct mammal. Even if science were able to settle the time of the great extinction, we should be only a little better off. We could say that man was in the New World at that time; but this would give us only an upper date, not a lower one. Man may have been here for tens of thousands of years before those mammals died off. A few scientists think he was.