hese islands are situated in the same latitude
as the northern part of Novaya Zemlya,--indeed, not far south of the
latitude of Spitsbergen,--the fact of such huge mammals having been able
to find subsistence there at apparently quite a recent geological period
seems an astounding fact. It may be urged that their bones might have
been carried so far north by ice, or by some other equally powerful
agency. But Tcherski and all other palaeontologists who have examined
these northern deposits are unanimous in the belief that these
herbivores and carnivores lived and died where their remains are now
found. "It is evident," says Tcherski (p. 451), "that these large
animals could only have lived in those extremely northern latitudes
under correspondingly favourable conditions of the vegetation, viz.,
during the existence of forests, meadows, and steppes." He also is of
opinion that the moist climate which evidently prevailed in Europe
during Post-tertiary (Pleistocene) times must have modified the Siberian
climate in so far as to render it milder. The existence of the
Aralo-Caspian basin (Fig. 12, p. 156) must also have tended in the same
direction. It appears then that, at the time when plants and animals are
believed to have retired southward in Europe before the supposed
advancing Scandinavian ice-sheet, no agency existed in North Siberia
which was able to suppress and to annihilate the forest and meadow
vegetation, and drive away the fauna connected with it. We know,
continues Tcherski, that such genera as Bison, Colus (_Saiga_),
Rhinoceros, Elephas, and Equus are met with in all horizons of the
diluvium of West Siberia. He therefore comes to the conclusion (p. 474),
that these and other facts imply that the retreat of the North Asiatic
fauna commenced about the end of the Tertiary Era (Pliocene), and that
it was continued very slowly throughout the Post-tertiary (Pleistocene)
Epoch, without any visible changes in its southward direction, even
_during the time of the most important glacial developments in Northern
Europe_. Only after the conditions disappeared which had produced the
augmentation of an atmospheric moisture, did the climate of North
Siberia become deadly to a temperate fauna and flora. Tundras then
spread over the meadow-lands and remnants of forests, whilst arctic
animals replaced the large ungulates and carnivores which had wandered
far away from their native southern home.

This is Tcherski's explanation