Humans have been homogenizing the mammal communities of North America for 10,000 years, whether by spear or plow, according to new research led by the University of Nebraska-Lincoln and the Canadian Museum of Nature. Kate Lyons of the University of Nebraska, Danielle Fraser of the Canadian Museum of Nature, and international colleagues examined 8,831 fossils representing 365 mammal species from 366 sites across North America. Using those fossil records, the team was able to assess homogenization: the degree to which the specific mammal species in one ecological community resembled the species composition of its surrounding communities. A few previous studies,