Columbian Mammoth

*Mammuthus columbi*

Karen Carr Artwork

The **Columbian Mammoth** (*Mammuthus columbi*) is an extinct species of elephantid mammoth of the Quaternary period that appeared in North America (in the present United States and to as far south as Nicaragua and Honduras) during the late Pleistocene. M. imperator is a synonym of the Columbian Mammoth. It's said to be a hybrid descendant of the Woolly Mammoth and a lineage related to the Steppe Mammoth.

The Columbian Mammoth was one of the last members of the American megafauna to go extinct, with the date of disappearance generally set at approximately 12,500 years ago. However, several specimens have been dated to 9,000 years ago or less and one near Nashville, Tennessee was reliably dated to only about 7,800 years ago.The Columbian mammoth was one of the largest of the mammoth species and also one of the largest elephants to have ever lived, measuring 4 meters (13 ft) tall and weighing up to 10 metric tons (11 short tons). It was 10.7 feet (3.3 m) long at the shoulder, and had a head that accounted for 12 to 25 percent of its body weight. It had impressive, spiral curved tusks which typically extended to 6.5 feet (2.0 m). A pair of Columbian Mammoth tusks discovered in central Texas was the largest ever found for any member of the elephant family: 16 feet (4.9 m) long.

It was a herbivore, with a diet consisting of varied plant life ranging 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.

## Taxonomy

The Columbian mammoth was first scientifically described in 1857 by naturalist Hugh Falconer, who named the species *Elephas columbi* after the explorer Christopher Columbus.

A 2011 genetic study showed that examined *M. columbi* specimens were grouped within a subclade of woolly mammoths. This suggests that the two populations interbred and produced fertile offspring. It also suggested that a North American form known as *Mammuthus jeffersonii* may be a hybrid between the two species.

Larry Agenbroad, a respected researcher, believes that the *M. imperator* is a non-valid name given to unusually large *M. columbi*. Given that that proboscidean tusks grow throughout the animal's life, older animals will tend to have longer tusks, and so are more likely to cross. He has also mooted the alternative interpretation that *M. imperator* represents a subspecies of large *M. columbi*. This has also been accepted by other scientists.

The Columbian mammoth was one of the last members of the American megafauna to go extinct, with the date of disappearance generally set at approximately 12,500 years ago. However, several specimens have been dated to 9,000 years ago or less, and one near Nashville, Tennessee, was dated to only about 7,800 years ago. However, dates younger than 11,000 BP have not been viewed as credible.

### Evolution

The earliest known proboscideans, the clade which contains the elephants, existed about 55 million years ago around the Tethys Sea area. The closest relatives of the Proboscidea are the sirenians and the hyraxes. The family elephantidae existed six million years ago in Africa, and includes the living elephants and the mammoths. Among many now extinct clades, the mastodon is only a distant relative of the mammoths, and part of the separate *mammutidae* family which diverged 25 million years before the mammoths evolved. The following cladogram shows the placement of the Columbian mammoth among other proboscideans, based on hyoid characteristics.

## Description

The Columbian mammoth was a savanna and grassland inhabitant, similar to the modern African elephant. Large males ranged from 3.7–4.0 m (12.1–13.1 ft) and weighed between 7–9 metric tons (7.7–9.9 short tons) with spiralled tusks that could grow up to 4.25 metres (13.9 ft) long.

It was a herbivore, with a diet consisting of varied plant life ranging 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.

Hair believed to have belonged to the Columbian mammoth has been discovered in the Bechan Cave, Utah, where mammoth dung has also been found. Some of this hair is coarse, and identical to that known to belong to woolly mammoths. Since this location is so far south, it is unlikely the hair belonged to woolly mammoths. The distribution and density of this fur on the living animal is unknown.

## Fossils

The remains of Columbian Mammoths were discovered in the La Brea Tar Pits, located in Los Angeles, California, and the skeleton of one of them is on exhibit in that site's museum. The Waco Mammoth Site in Waco, TX holds the record for the largest known concentration of skeletons of mammoths believed to have died in the same event. This mammoth also lived in Mexico, where its remains are very common. A large individual is the central exhibit in the Regional Museum of Guadalajara, in the Mexican state of Jalisco.

In 1998, the Washington State Legislature approved the Columbian Mammoth as the State Fossil.

## Appearance in other media

### *Jurassic Park*

* Mammuthus columbi appeared in the Jurassic World book Dinosaur-digs, showing a photo of the famous sculpture from Rancho La Brea in California.