The advance of the great Scandinavian glaciers from the north crowded to the south the Tundra or Barren Ground fauna of the arctic circle. The herald of this fauna during the First Glacial Stage was the musk-ox, which appears in Sussex, and then came the reindeer of the existing Scandinavian type. These animals are followed by the woolly mammoth (E. primigenius) and the woolly rhinoceros (D. antiquitatis) with their panoply of hair and wool which had long been developing in the north. Finally in the Fourth Glacial Stage arrived the lemming of the river Obi, also the more northern banded lemming, the arctic fox, the wolverene, and the ermine, as well as the arctic hare. These tundra mammals for a short period mingled in places with survivors of the African-Asiatic fauna, such as Merck's rhinoceros and the straight-tusked elephant (E. antiquus). In general, they swept southward as far as the Pyrenees over country which had long been enjoyed by the African-Asiatic mammals, while the hippopotami and the southern elephants retreated still farther south and became extinct.
The only survivors of the great African-Asiatic fauna in Fourth Glacial and Postglacial times were the hyænas (H. crocuta spelæa) and the lions (Felis leo spelæa). The lion frequently appears in the drawings of the cavemen.
The various species belonging to these five great faunæ apparently succeed each other, and wherever their remains are mingled with the palæoliths, as along the rivers Somme, Marne, and Thames, or in the hearths of the shelters and caverns, they become of extreme interest both in their bearing on the chronology of man and on the development of human culture, art, and industry. They also tell the story of the sequence of climatic conditions both in the regions bordering the glaciers and in the more temperate regions remote from the ice-caps. Thus they guide the anthropologist over the difficult gaps where the geologic record is limited or undecipherable. The general succession of these great faunæ is illustrated in Fig. 14 and also in the above table.
(1) Lamarck, 1815.1.
(2) Schaaffhausen, 1858.1.
(3) Darwin, C., 1909.2.
(4) Lamarck, 1809.1.
(5) Lyell, 1863.1, pp. 84-89.
(6) Darwin, C., 1871.1, p. 146.