April 4, 2022 Scott Kraus

From Brontosaurus To Apatosaurus – The Name Change

When the first Apatosaurus fossil was discovered in 1877, the name was bestowed but forgotten because the archeologist who named this dinosaur became enraptured with another discovery. The second set of fossils were called Brontosaurus and thought to be a different dinosaur altogether.

When researchers discovered these two were one in the same, the name Brontosaurus was already more popular than the title Apatosaurus. Therefore, there’s understandably confusion when someone is talking about the Brontosaurus but using the Apatosaurus title. Most people are more familiar with the television coined term “long neck,” when either name is acceptable because it’s describing the same dinosaur. That doesn’t stop some scientists from petitioning to have the name “Brontosaurus” alone as these dinosaurs’ main identity — a name most paleontologists grew up being familiar with. Below we’ll discuss what makes this double-dubbed dinosaur unique to the late Jurassic period and how it’s discovery has impacted science.

Quick Facts

What Did Apatosaurus Look Like?

Apatosaurus Was A Late Jurassic Sauropod

Apatosaurus has been described as the original ‘gentle giant.’ Huge and harmless, these late Jurassic sauropods were easy prey for vicious predators — their only defenses being a thick whip-like tail and sheer body mass. With all the controversy surrounding their names, it’s no surprise that the meaning of Apatosaurus is “deceptive lizard,” but not for the mix-up reasons that most people would assume.

Instead, the term ‘deceptive’ here describes how the original archeologist who found the fossils was deceived to believe this was an underwater dinosaur. With a vertebrae reminiscent of mosasaurs, the Apatosaurus was once thought to be a sleek and fierce marine carnivore, rather than a lumbering herbivore. Albeit, the Apatosaurus’s other name (Brontosaurus) means “thunder lizard” — a definition that more accurately describes the elephantine plant-eater.

Physical Attributes of Apatosaurus

As one of the largest land animals to have ever existed, the Apatosaurus towered over the biggest predator; an Allosaurus who was shorter by 3 inches to the herbivore’s estimated highest height of 17 feet. Weighing in betwixt 33-40 tons, the Apatosaurus was gigantic!

Measuring between 70-90 feet long, the Apatosaurus had an extremely long neck with a smaller head, complete with pencil-shaped teeth that were perfect for munching leaves. It’s unknown whether the Apatosaurus walked with it’s head up or kept it’s neck out straight while walking. Also unknown is why the dinosaur’s nostrils were located on the top of their head.

The Long Neck of Apatosaurus

The long neck of the Apatosaurus had surprising limited mobility. It’s theorized that if the Apatosaurus extended it’s neck in an upright position, it could put too much stress on their heart — resulting in instantaneous death. Instead, the 40 foot long appendage could only be lifted a maximum of 15 feet off the ground; a far-cry from the popular myths in modern movies.

What Did Apatosaurus Eat?

Going with the theory that the Apatosaurus held it’s neck parallel to the ground, the dinosaur may have eaten vegetation in a “mowing” fashion — devouring large swaths of leaves off lower branches. The purpose of the long neck was to ‘peek’ into overgrown woodland areas where other herbivores would have trouble going. If swamp-like conditions kept the other dinosaurs from eating the horsetails and ferns, the Apatosaurus could maneuver through on  a longer neck — snagging more vegetation and eating their fill of untouched foliage.

Apatosaurus was also one of the only large dinosaurs to officially use “gastroliths” — an ingestion of rough stones that the dinosaur would swallow to help grind up tough plant matter in their digestive tract.

How Did Apatosaurus Move?

The Apatosaurus walked on 4 legs — moving at a slow trudge but covering quite a bit of distance in a short span of time with trunk-like appendages. Fossilized footprints of these dinosaurs have been measured at up to a yard long and imprinted deeply into the ground.

Most of their weight was carried around their midsections and legs — however, it was all muscle. With the effort it took to move, these dinosaurs never accumulated fat — constantly burning the calories they had eaten while on the search for more fuel for their large body. It’s estimated that the Apatosaurus  couldn’t move any faster than 9 mph.

Interestingly enough, the Apatosaurus hatchlings were light on their feet — considered bi-pedal through their first few months of life. Afterwards, they’d start developing like the adults, becoming heavier as time wore on and losing the ability to walk comfortably or safely on their hind-legs.

Apatosaurus Predators

Apatosaurus had one main predator — the Allosaurus; an intelligent carnivore who would disregard the size of an herbivore if it were easy prey. Despite fossilized remains of the Allosaurus showing fractures from the tail of the Apatosaurus, it’s still believed that the Apatosaurus was it’s main menu herbivore. Unfortunately, because the plant-eater was so big, it would fall hard — meaning if a predator could maneuver in just the right way and bring the Apatosaurus down, it would be at the mercy of aforementioned predator.

Sometimes, size was also on the herbivore’s side. Lesser predators avoid the Apatosaurus because of it’s long tail that could do damage when swung like a giant whip. There was also the defense of a much higher neck, giving protection from being fatally bitten in an essential artery while standing.

The History Of Apatosaurus Discovery

Where Did Apatosaurus Live?

It’s said that if these dinosaurs didn’t succumb to death in any number of ways, they had a life-span of a century or more. Their most frequent habitats were in the North American woodlands — places where vegetation flourished; there was plenty to eat, small lakes provided ideal drinking water, and there were a few places to hide in case of predatory attack. The majority of fossils have (thus far) been found in Colorado, Oklahoma, Utah, and Wyoming.

Apatosaurus Specimen Discovery

The infamous paleontologist, Othniel C. Marsh, unearthed the first Apatosaurus fossils in 1877. Coincidentally, after the name was coined, he discovered another set of fossils and accidentally assumed these two dinosaurs were different. Thus, the double-name for the Apatosaurus was born. The vertebrae bones found by Marsh had distinct teeth marks in them that were later said to have been made by the Allosaurus.

Unfortunately, a complete fossilized Apatosaurus wasn’t found until 1915 — when Earl Douglass found the first skeleton with a Apatosaurus skull still attached. The proverbial wires between archeologists were crossed and when Douglass died in 1932, the wrong skull was used in an Apatosaurus exhibit. It wasn’t until 1975 that a paleontologist by the name of Jack McIntosh realized the mistake and had the real Apatosaurus skull sent to the museum where it resides on the first fully fossilized Apatosaurus remains to this day.

The Importance of the Apatosaurus

Apatosaurus has caused dispute because of the century-old naming mistake. Despite the many labels associated with this dinosaur, the characteristics and unique nature of the Apatosaurus has made it one of the most popular creatures to have ever existed. Featured in movies, books, and interesting television specials, Apatosaurus is one of the first dinosaurs ever taught to children — one of the first to ever be familiarized within the paleontological field.