from the La Brea Tar Pits Website:
An average Columbian mammoth stood over 12 feet tall at the shoulder and weighed over 10,000 pounds. The mammoth’s primary diet consisted of grasses, which was quite different from the diets of their modern relatives, the Indian and African elephants. Yet, like these elephants, the Columbian mammoth had a set of four teeth that was replaced by new sets as the older teeth eventually became worn. This type of tooth replacement continued to produce six sets over the course of about 60 years and then, like all elephants, the mammoth would starve as the final set wore out.
The Colombian Mammoth (Mammuthus columbi) was an herbivore, and ate a variety of plant life from grasses to conifers. It is also theorized that the Columbian Mammoth ate the giant fruits of North America such as the Osage-orange, Kentucky coffee and Honey locust as there was no other large herbivore in North America then that could ingest these fruits. Using studies of African elephants, it has been estimated that a large male would have eaten approximately 700 pounds (320 kg) of plant material daily. The average Columbian mammoth ate 300 pounds of vegetation a day.
These mammoths had huge spiraling tusks that grew up to sixteen feet in diameter, making them record holders among all elephant species. Colombian Mammoths are the largest species to have been unearthed at the La Brea Tar pits. The largest mammoth recovered at La Brea weighed over 4 tons and stood over 3 and a half meters tall.
Columbian mammoths ranged through the southern half of North America and south into Mexico before becoming extinct about 12,500 years ago – close to the same time the first humans migrated into North America.