Mammoth tusks weighing 125 and 200 pounds each, found at Sulphur Creek, Yukon, Canada, in 1906 (?). Source: Yukon News.
which reminds me
Nadezhda Ladygina-Kohts (1889–1963), Russian zoopsychologist (why yes, it is a thing, thank you for asking). Source: Alexander V. Markov @ LiveJournal.