Elephant bones by the Volga: war elephants, not the Flood
Editorial contextA broken elephant tusk nearly a metre long had washed out of a river bank, and human bones and broken iron spearheads had been found nearby. Lepekhin sets aside the theories that the far north was once hot, that the Flood carried the beasts there, or that they were freaks of nature. He argues instead that Asian peoples trained elephants for war, that these animals were buried only a few hundred years ago, and that Tatar-style armies would never have bothered to saw off the tusks.
That some of the Asiatic peoples trained elephants for fighting and battle is, in my opinion, surely a well-known fact. Accordingly my view is that these foreign corpses were buried not far from the Volga not many thousands but a few hundred years ago. … [another thing is] to saw off elephant tusks and drag them away, especially when we consider the way the Tatars are used to going to war.
Working translation
Original wording
Daß aber die asiatischen Völker zum Theil Elephanten zum Gefecht und zur Schlacht abgerichtet haben, ist ja wohl, meines Erachtens, eine bekannte Sache. Und diesemnach ist meine Meynung, daß diese ausländischen Leichen nicht vor vielen tausend, sondern vor etlichen hundert Jahren nicht weit von der Wolga begraben worden sind. … Elephantenzähne abzusägen und mit fortzuschleppen, zumal wenn wir die Art bedenken, wie die Tatarn zu Felde zu ziehen pflegen.
About 'Asiatic peoples' and Tatar armies (Lepekhin's theory)
Keep in mind
He saw the tusk; the war-elephant explanation is his own guess. Such tusks are now known to be fossil mammoth ivory, and he himself mentions 'mammoth bones' from Siberia on the same page.