In the early 1970’s a bighorn sheep (Ovis canadensis) skull estimated to be 9280 years old was unearthed in a gravel pit just south of the Peace Arm of the Williston Reservoir, just north of Mackenzie, BC. This discovery supports the theory that bighorn sheep and thinhorn sheep (Dall’s and Stone’s)are evolutionarily distinct from each other and the Peace River is the historical border of the two species’ distributions.
: Rutter, N. W., V. Geist, et al. (1971). “A bighorn sheep skull 9280 years old from British Columbia.” J. Mammalogy 53(3): 641-644.