PLEISTOCENE PERIOD: 250,000 - 10,000 years ago
Emerging 55 million years ago, the group of mammals called Proboscideans are identified by the presence of tusks and a trunk and include mammoths, mastodons and elephants. The oldest mammoth remains have placed the beginnings of the beasts in Africa but eventually, they migrated to Europe and Asia.
The Columbian Mammoth (Mammuthus columbi) was a massive Ice Age beast and a descendant of Mammuthus eridionalis, an earlier species that migrated across the Bering Land Bridge into North America around one million years ago. The Columbian Mammoth ranged from Alaska to Florida and as far south as Mexico and Central America. While most think of the Woolly Mammoth to be large, it was not and especially when standing alongside the giant Columbian Mammoth. The Columbian Mammoth stood almost 14 feet at the shoulder as opposed to the Woolly Mammoth who stood only about 9 feet at the shoulder. The Columbian Mammoth was the first immigrant lineage of mammoths into North America. They became extinct 11,000 years ago along with all other Proboscideans in North America. Associated Paleo-Indian stone tools have been found at some fossil sites indicating these massive beasts were hunted by early North American Indians.