Domesticated animal bones are rarely found in archaeological sites. Of course large boned animals will leave more evidences than small ones. Once bones are found, the dating of the bones becomes the final hurdle. Thus, the paradigm one has will affect the interpretation given. The Smithsonian for example has shown a bias against creationist scientist, despite the overwhelming evidence in their favor.  

It appears by the statements of the Highlanders, there are larger animals in the interior. On seeing the head of Taurus, one of the signs of the Zodiac, the women know how to explain that it is a horned head of a large animal, wild animal which inhabits the distant country, but not theirs..” (E.B. O’Callaghan, The Documentary History of the State of New York, 1850, p. 22)