Einiosaurus

Discovered in a Native American Sacred Site: Named After the “Buffalo”

A Rare Dinosaur Exclusive to Montana

Fossils of Einiosaurus were discovered in the present-day state of Montana, United States.
To this day, fossils of this dinosaur have only been found in Montana, making it a very regionally specific existence.

Meaning of the Scientific Name: “Buffalo-like Reptile with a Forward-Curving Horn”

Notably, the initial discovery site was within a Native American reservation (a sacred site).
In honor of this discovery location, their language was incorporated into the scientific name.

Einio

Means “buffalo” in the language of the Blackfoot tribe of Native Americans.

In other words, Einiosaurus means “Buffalo Lizard” (or Buffalo-like reptile) in the Blackfoot language.
The scientific name Einiosaurus procurvicornis, formally named in 1995, encompasses the meaning “Buffalo-like reptile with a forward-curving horn,” a name that beautifully fuses its distinctive appearance with local culture.

*Note: However, its actual movements are believed to have been much slower than a buffalo, incapable of running violently.

A Nose Horn Like a “Giant Can Opener” and a Unique Head

While Einiosaurus falls into the somewhat smaller category among ceratopsians, which include giant species, its head possessed a striking individuality.

A “Nose Horn” Curved Like a Reverse Hook

Its greatest feature is the shape of the horn on its nose.
It curled downwards toward the front, drawing a spectacular “reverse hook” arc.
Its shape is described as drooping forward like “melted soft-serve ice cream” or resembling a “giant can opener.”

Described as “melted soft-serve ice cream” or a “giant can opener”

Frill Spikes to Boost Defense

On the frill (neck shield) at the back of its head, there were large curved horns or two long, sharp, thick spikes, which enhanced its rear defense.
The skull itself was about 1.5 meters in size, which was compact compared to similar ceratopsians (which could reach the 3-meter class).

Unsuited for Battle? The Role of the Enigmatic “Curved Horn”

A horn so extremely curved and pointing downwards is clearly unsuitable as a weapon for piercing enemies.
Why it took this shape remains a subject of debate, with the following theories primarily proposed.

Theories Regarding Usage

Foraging Tool Theory

Used to dig up plant roots or rhizomes growing in the ground.

Defense Theory

While the shape was not ideal, it also served to protect against enemies.

Display Theory

Used for species identification or to appeal to the opposite sex (display).

Theories Regarding Formation Factors

Malformation/Mutation Theory

Could it be that an individual with a curved nose was simply born by chance due to a genetic mutation?

Fossil Deformation Theory

Could the fossil itself have been deformed as a result of compression within the geological strata?

In fact, since only one fossil with a well-preserved snout has been discovered so far, the truth remains a mystery.

Evolutionary Missing Link Theory

It was once thought that this unique horn might be a “missing link” showing the process of evolution.
The speculation is that it is an intermediate species where the horn gradually curved forward during the evolution from the nose-horn-developed “Styracosaurus” to “Pachyrhinosaurus,” which possessed a large boss instead of a horn.

Life in “Herds” and Sociality as Told by Bone Beds

Traces of Mass Death by Flood or Drought

Einiosaurus is believed to have lived in “herds” rather than alone.

Believed to have lived in “herds” rather than alone

The basis for this is the bone bed (a dense concentration of bones) at the “Dino Ridge Quarry” in the Two Medicine Formation of Montana.
Here, hundreds of bones representing more than 15 individuals were found at once, suggesting a high possibility that the entire herd perished simultaneously after being caught in some sudden accident or disaster (such as a flood or drought).

Protecting Themselves in Multi-Generational Herds

The discovered fossils included individuals of various ages, indicating that they formed herds containing everything from adults to children.
Ferocious predators such as Daspletosaurus existed in North America at that time.
For the Einiosaurus, which was not fast on its feet, forming herds was likely the best survival strategy to deter attacks from predators.