Columbian mammoth
The Columbian mammoth ("Mammuthus columbi") produced a separate, isolated population at the end of the Pleistocene on the Channel Islands of California, most likely about 40,000 years ago (although the time of isolation is not fully known). Selective forces on the Channel Islands resulted in smaller animals, forming a new species, the pygmy mammoth ("Mammuthus exilis"). Channel Islands mammoths ranged from 150–190 cm in shoulder height.