The lands taken up by members of the Callahan family from the 1870s through the 1890s may have been occupied by others in the 1850s and 1860s, but no deeds were located.
The California red-legged frog, made famous in Mark Twain’s 1865 "The Celebrated Jumping Frog Of Calaveras County" but feared absent from the county by 1969, was rediscovered in 2003.