April 4, 2022 Scott Kraus

Diplodocus was a Jurassic Sauropod

Diplodocus walked the Earth about 150 million years ago in the late Jurassic Era. At the time of its discovery, Diplodocus was the longest dinosaur on record. It has since been out-measured by the likes of the Supersaurus or the rarely-mentioned Futalgnkosaurus, but Diplodocus played an important role in fueling the public’s imagination about prehistoric animals.

Quick Facts

About Diplodocus

Diplodocus, pronounced di-PLOD-o-kus, received its name from the double-beamed chevron bones found in its tail. Diplodocus is a Neo-Latin term from two Greek words meaning “double” and “beam”. The double-beamed bones are thought to have been necessary for protecting, stabilizing, and controlling the massive tail of Diplodocus. These dinosaurs are a common find in the Upper Morrison Formation and dozens of specimens have been recovered since its discovery.

What Did Diplodocus Look Like?

During the Jurassic Era in western North America, herds of Dipodocus slowly lumbered about searching for foliage to eat. One of the longest dinosaurs ever discovered, Diplodocus could grow to over 100 feet long. Contrary to movie and cartoon depictions, this dinosaur’s posture was nothing like that of a giraffe. Paleontologists infer from the fossil remain that both the neck and tail were held parallel to the ground. Skin fossils show that small spikes were present above the spine running from the upper part of the neck down to the tail.

At the end of its long neck was a small head suited for stripping leaves off of branches. At the other end was a 30-foot-long tail that might have had a primary role as a counterbalance. Some experts suggest that it may have also been used as a defense mechanism to ward off predators, but with such a heavy and lengthy neck being held up in a horizontal position, it’s hard to imagine the body and legs supporting that weight.   

What Did Diplodocus Eat?

Diplodocus was a strict herbivore. Fossil records show wear that indicates that it used its small head and slender teeth to reach into groups and of trees and strip branches of edible fibrous material. Conifers were the most abundant tree during the Jurassic Era, so it is safe to assume that these trees made up a large part of the Diplodocus diet. It is also thought that it fed on ferns, bushes, and the foliage of other trees. Studies of the skeletal structure of Diplodocus lead paleontologists to believe that Diplodocus could rear up on its hind legs to reach food high in the tree tops, allowing it to feed on many different levels. Some experts hypothesize that they were also capable of reaching, with their long necks, into marshes and swamplands to eat soft water plants, perhaps even submerged plants. This dinosaur had to eat so much at its size it is hard to believe that it had a limited menu.

How did Diplodocus Move and Migrate?

Just like the rest of the sauropods, Diplodocus was a quadrupedal walker. The feet of a Diplodocus were similar to those of a modern-day elephant and both animals are large and sturdy creatures, so their walking motion should be similar. Paleontologists use fossilized tracks, leg length, and mass to determine how dinosaurs walked and their research suggests that Diplodocus wasn’t much of a runner. The limbs of Diplodocus weren’t built for the stresses of jogging or trotting. Even though Diplodocus only moved at a walking pace, its long legs and huge size made it possible for this dinosaur to move at an estimated 12-22 miles per hour.

Due to their large diets and herding tendencies, groups of Diplodocus were constantly on the move in search of food. When the food supply in their area became depleted, the moved elsewhere throughout the western North American continent to graze.

Where Did Diplodocus Live?

A great number of Diplodocus fossils have been unearthed and they give us a good idea of what area these herds inhabited. Diplodocus discoveries have been made in Colorade, Utah, Montana, and Wyoming, so there is reason to believe that they stayed in the western-most part of North America. Future discoveries may extend this range.

The Discovery of Diplodocus

Samuel W. Williston was digging around in Canon City, Colorado when he discovered the first Diplodocus fossil. What he found while excavating in the Upper Morrison Formation was a partial skeleton that included the double-beamed chevron bones. These bones, which support a long, heavy tail and protected blood vessels and nerves, were used by Othniel C. Marsh a year later to name the fossil. This initial find took place in 1877. Since then, many more fossils have been recovered and complete fossils can be viewed in a number of museums.

How Did Diplodocus Grow To Such Lengths?

The diverse Diplodocus fossil collection allows paleontologists to chart the growth of this dinosaur. They used recovered fossils, which were preserved at different stages of growth, to reach the conclusion that Diplodocus grew at a very fast rate. This wasn’t a surprise since a Diplodocus hatchling grew to over 100 feet long during its lifetime. Another discovery that was made through this research was the age at which these sauropods reached maturity. Current statistics reveal that Diplodocus was sexually mature just 10 years after birth. At this point, they would not have reached their maximum size so growth continued well after maturity.

What does Andrew Carnegie Have To Do With Diplodocus?

On the grounds of the Carnegie Institute and Library in Pittsburgh, Pennsylvania, a giant fiberglass model of a Diplodocus imposes its presence on anyone that passes by. But just what is a Diplodocus reconstruction doing on a Carnegie institution? Well, in 1899 Andrew Carnegie funded an expedition to recover a Diplodocus fossil in the Upper Morrison Formation. He had funded prior expeditions, but his excavators had no luck in finding a fossil. This time, however, they located a Diplodocus specimen that turned out to be a new species. The new species was named Diplodocus carnegii in honor of Mr. Carnegie and was set up in Carnegie’s museum for all to see.

Carnegie’s Diplodocus adventure didn’t stop there though. Supposedly, King Edward VII of England viewed a sketch of Diplodocus in Carnegie’s Skibo Castle in Scotland and inquired about attaining a specimen to put in the British Museum. Carnegie hired workers to get busy creating a plaster duplicate and in 1905 it was completed. Once prominent leaders of other European countries heard about the Diplodocus recreation, they went to work acquiring their own models. Nobles from European countries such as France and Germany contacted Carnegie about acquiring recreations so Carnegie created more duplicates for their respective museums. Now, thanks to Andrew Carnegie, Diplodocus is one of the most widely recognized dinosaurs and millions of museum visitors have had the chance to behold the immense size of this dinosaur firsthand.

The Importance of Diplodocus

Diplodocus is vital to the study of growth and development in dinosaurs because fossils have been preserved at many different stages of growth. Since Diplodocus grew to over 100 feet, paleontologists perform research in an attempt to figure out how they grew to such massive sizes. This research could also provide insight on how reptiles were able to reach great sizes in general and dominate the animal kingdom.

Diplodocus also played an important role in familiarizing the public with dinosaur discoveries. During the golden age of dinosaur discovery in the late 19^th century, hundreds of species were discovered and paleontologists were frantically trying to categorize and label all of their findings. With the help of leaders like Andrew Carnegie, Diplodocus fossils and molds were pieced together for display in museums across the nation. This display of Diplodocus fueled the public’s desire for dinosaur knowledge and ultimately led to funding and future discoveries.