key point
- Equus giganteus existed from the Blanconian period to about 12,000 years ago, near the end of the Pleistocene.
- If Equus giganteus still existed today, it would be easy to compare it to the grizzly bear.
- Equus giganteus is a species of horse that also lives in North America.
Would you believe it if we told you that there was a horse that was bigger than most land mammals? The discovery of a breed of horse bigger than a grizzly is pretty amazing. Not just because it’s found in North America, but also because of its size.
This particular horse species is Equus giganteus, an extinct horse thought to be a prehistoric species that lived during the Pleistocene Epoch and was first discovered in Idaho in 1932.
Paleontologists examined the fossilized remains of the species, and they were able to determine that it was indeed a unique species of horse.
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Below, we discuss the gigantic size of the horse, which was larger than a grizzly bear, and how it compares to other species today.
giant horse

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Equus giganteus existed from the Blanconian period (overlapping with the early Pliocene on the geological time scale) to about 12,000 years ago, near the end of the Pleistocene. The name of the horse literally means “giant horse”. It fits the animal because it’s essentially a giant modern horse.

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According to the researchers who discovered the species, its estimated weight was around 2,600 to 3,300 pounds. That means it can weigh more than two adult grizzly bears!
It will be interesting to see how Equus giganteus towers above other giant mammals today. Below is a list of mammals compared to Equus Giganteus.
Equus Giganteus and Grizzly Size Comparison

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If Equus giganteus still existed today, it would be easy to compare it to the grizzly bear. Equus is unquestionably larger than a Grizzly and weighs more than twice as much!
Grizzlies are a subspecies of brown bear found in North America. Grizzlies are brown, although their fur can be tipped white or off-white, hence the name. Grizzlies are legally protected in the continental United States but not in Alaska, despite recent controversial attempts to repeal such laws.
Equus giganteus is a species of horse that also lives in North America. This is a very large breed of horse, with males reaching a height of 6.6 feet at the shoulder and weighing from 2,600 to 3,300 pounds. Females are usually smaller than males, reaching up to 5.2 feet at the shoulders and weighing up to 1,200 pounds.
Grizzlies, on the other hand, are also large animals, with males reaching lengths of up to 8 feet and weighing up to 600 pounds (270 kilograms). Females are usually smaller than males, but can still reach 6 feet in length and weigh up to 300 pounds (135 kilograms).

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Modern Horses and Giant Horses
The modern horse is the perfect animal for a number of reasons. They can be used for riding, racing, or simply as workhorses on the farm. However, modern horses are smaller in size and weight than giant horses. For example, the average modern horse is about 4 feet tall and weighs between 900 and 2,000 pounds, depending on the breed.
The differences between these two horses can be attributed to their evolutionary history. Equus giganteus was able to grow to such a large size due to thousands of years of evolution and natural selection while modern horses were domesticated by humans. Experts bred them for specific purposes, such as riding horses or pulling carts; thus, they were smaller than their wild ancestors.

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Bison vs. Equus Giganteus
We all know that bison are large mammals native to North America, distributed in many places such as Alaska and Canada. They feed on grasses and other vegetation around lakes or rivers, which helps keep these areas healthy by preventing erosion during floods or droughts caused by climate change.
Now, how big is a bison? Bison are large animals weighing up to 2,000 pounds. They have long, bushy hair and horns about two feet long. In contrast, Equus giganteus is a horse that typically weighs around 2,600 pounds.
The size difference between the two animals is quite significant, but both have their own strengths. Apparently, Equus Giganteus was larger than the bison.
Rhino vs. Equus Giganteus

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The rhino is a large herbivorous mammal native to Africa and Asia. Rhinos are one of the largest animals on Earth and one of the most endangered in the world. The two types of rhino that exist today are the white rhino and the black rhino.
White rhinos are native to southern Africa and can be found in grasslands and open woodlands. It can weigh from 4,000 to 5,500 pounds and grow up to 11.5 feet long. The black rhino is native to East and Central Africa; it weighs an average of 1,760 to 3,090 pounds and can grow to be 9 to 12 feet long.
Considering the size a rhinoceros can grow to, it is thought to be larger than Equus giganteus. Rhinos are the second largest land mammal after elephants and can weigh up to 6,000 pounds. Giant horses, on the other hand, can theoretically grow up to 9 feet tall and weigh up to 3,300 pounds.

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Are modern horses direct descendants of giant horses?
In the western United States, there are herds of “wild” horses roaming freely on the plains. Are these the ancestors of an ancient breed like Equus giganteus? The answer is no. Equus giganteus and other prehistoric species went extinct along with mammoths and dire wolves during the last ice age. However, horses in other parts of the world did not become extinct, and people in other parts of the world began to domesticate horses about 4,000 years after the North American horse breeds disappeared.
There were no horses in North America until the Spanish brought them home to where they first evolved in the 1400’s. Many of these domesticated horses escaped captivity, returned to their original habitats, and spread across the country. Native Americans began trapping and riding horses, spreading them further throughout North America.

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