5 Most Gigantic Prehistoric Mammals to Ever Walk the Earth–Warm-Blooded Dinosaurs, Practically

July 20, 2019 Updated: July 20, 2019

Dinosaurs are arguably the most popularized giants of the animal kingdom to ever roam the earth. However, let’s not forget that there are some pretty stupendous mammal species that came after the dinosaurs that are often overshadowed by their reptilian predecessors.

After the dinosaurs died out some 65 million years ago, the size and diversity of mammals exploded, resulting in enormous species undreamed of in modern times. There were rodents that weighed over a ton and giants herbivores that weighed as much as five elephants.

We think that these oft-unsung, warm-blooded giants deserve a moment. So, here are five of the biggest mammalian creatures from prehistory ever to walk the earth.

1. Mastodon

Mastodons are enormous, giant relatives of the elephant species that walked the earth over 15 million years ago. They are a member of the mammut genus. The first trace of this species found was a tooth that was discovered in 1705 in New York. The tooth weighed approximately 5 pounds (approx. 2 kg), astoundingly.

Mastodon (©Shutterstock | Brooke Crigger)

The mastodon had cusp-shaped teeth, a unique feature that distinguished it from mammoths. Its tusks were long and had deep curvature. Mastodons were herbivores and stood at a height of about 14 feet. They weighed approximately 7 tons.

This species went extinct approximately 11,000 years ago—before mammoths did.

2. Paraceratherium

An enormous relative of modern-day rhinos, the paraceratherium was believed to have grown to over 26 feet in length, weighing as much as 20 tons, making the paraceratherium the largest land mammal known to man.

Paraceratherium (©Shutterstock | AKKHARAT JARUSILAWONG)

Unlike its rhino relatives, there is no trace of any horn on its head, and it had a long neck and long legs, allowing it to reach higher into the trees to feed on a herbivorous diet.

The paraceratherium lived in the European and Asian continents approximately 35 million to 20 million years ago.

3. Elasmotherium

Another giant relative of the rhinoceros is the elasmotherium, or giant rhinoceros, also called the Siberian unicorn for its enormous horn on the top of its head. Although no horn fossils have been found to date, it’s estimated to be around 3 feet in length. As its name suggests, they were believed to be native to Siberia.

Elasmotherium (©Shutterstock | Daniel Eskridge)

The giant rhinoceros is herbivorous like its modern-day cousins but is much larger in size, double the size of a white rhino, weighing around 4 tons.

It is believed that they lived during the Late Pliocene through the Pleistocene periods and went extinct during the Ice age, some 35,000 to 40,000 years ago.

4. The Steppe Mammoth

The Steppe mammoth (mammuthus trogontherii) belonged to the same species as the woolly mammoth. It is estimated that this animal weighed over 10 tonnes. In comparison, the woolly mammoth was only a third the weight of the steppe mammoth. It is believed that the steppe mammoth originated from around the area which is today known as Siberia.

The Steppe Mammoth (©Shutterstock | Yakov Oskanov)

This species lived approximately half a million years ago, during the Pleistocene Age. As a grazer, it fed on tundra grass and used its tusks to scoop away snow to expose grass lying underneath it.

Steppe Mammoths lived on plateaus where food was available.

5. Titanotylopus

This species is a distant relative of modern-day camels but is much larger, weighing at least a ton. And like camels, they had a pronounced fatty hump on their back.

Titanotylopus is believed to have originated in North America before spreading to parts of Asia.

Titanotylopus (©Flickr | Dawn Pedersen)

The animal had large flat feet, a feature that allowed it to move easily on dry, rugged terrain, and it had large upper canines.

The giant camel relative was herbivorous, and it fed on plants. They went extinct approximately 30,000 years ago but had previously lived for over 10 million years.