| Name | Camptosaurus | Diet | Herbivorous |
| Name Meaning | Flexible lizard | Height | 1.4 meters (4.6 feet) |
| Pronunciation | Kamp-toe-sore-us | Length | 5-6.79 meters (4.6 feet) |
| Era | Mesozoic – Late Jurassic | Weight | 500-800 kilograms (1,102–1,764 pounds) |
| Classification | Dinosauria, Ornithischia, Ornithopoda | Location | North America, possibly Europe |
Camptosaurus Pictures
The Camptosaurus
Camptosaurus is the oldest genus in the ornithischian group of dinosaurs called Ankylopollexia.
It is believed to be an ancestor of later iguanodonts and hadrosaurids.
The Camptosaurus genus is surrounded by mystery in terms of fossil identification.
Over the years, numerous specimens were wrongly attributed to the genus, prompting specialists to name multiple species now considered invalid.
For this reason, many details regarding the true nature of Camptosaurus remain unconfirmed.
Although the genus is often listed as consisting of three species, two are under a question mark, awaiting full confirmation.
On the other hand, this is exactly what makes this late Jurassic plant-eating dinosaur so fascinating!
Physical Characteristics
The Camptosaurus is known from multiple fossilized specimens that differ in size.
Scientists estimated a length of 6.79 meters (22.3 feet) for some, while others are thought to have measured only 5–6 meters (16.4–`9.7 feet) long.
The same is valid for the weight.
While some individuals likely weighed 785–874 kilograms (1,731–1,927 pounds), others weighed only 500 kilograms (1,103 pounds).
Other members of the same clade, Ankylopollexia, which existed during the same period, meaning the Late Jurassic, were probably similar in size.
Their successors, however, diversified and evolved to grow much larger.
Shantungosaurus, for example, existed during the late Campanian and measured 14.7–16.6 meters (48.2–54.5 feet) long and weighed 16 metric tons (17.6 short tons).
Camptosaurus was heavily built.
Its forelimbs were short and likely bore five fingers, of which only the first three were clawed.
The fourth and fifth fingers had small nubs.
The hind limbs were robust, and its four-toed feet were broad.
The head was elongated, as the skull had a triangular shape and featured a pointed snout.
Some sources list that the Camptosaurus skull measured approximately 38 centimeters (15 inches) long.
Additionally, Camptosaurus also had a beak used to crop foliage.
Its teeth were probably placed remarkably close to each other on the jaw.
The neck of the Camptosaurus likely formed an S-shape.
The tail was quite long, starting with a broad shape and becoming very thin toward the tip.
Habitat and Distribution
If we were to judge by how many specimens were initially attributed to the Camptosaurus genus, we’d conclude that this creature had quite a wide distribution, having lived in North America and Europe.
However, further research revealed that multiple specimens were wrongly associated with the genus.
Then, they were reclassified, and the distribution of Camptosaurus was restricted to places that revealed officially confirmed fossils.
One location that Camptosaurus was undoubtedly an inhabitant of is Wyoming.
More precisely, its fossils were discovered in the Morrison Formation, one of the richest fossil-bearing sites in the United States.
Since the Morrison Formation extended beyond Wyoming, we cannot rule out the possibility that Camptosaurus roamed through those territories as well.
The Morrison Formation likely featured wet and dry seasons.
The ecosystem was excellent for the growth of ginkgos, tree ferns, cycads, and conifers.
Studies on the Lourinha Formation of Portugal, which is very similar to the American Morrison Formation in terms of habitat and climate, showed that it likely had an average temperature of 36 degrees Celsius (96.8 degrees Fahrenheit).
Since many dinosaurs discovered in the Morrison Formation were also recovered from the Lourinha Formation, we cannot rule out the possibility that Camptosaurus was indeed an inhabitant of Europe.
We only need more fossils to prove this!
Behavior and Diet
Camptosaurus was a herbivore. It had a highly efficient beak that helped it crop vegetation.
Additionally, it had strong teeth arranged tightly in the jaw.
Most recovered teeth show wear marks, indicating that their owners’ diet consisted primarily of tough vegetation.
Although quite bulky, Camptosaurus was probably a good runner and could achieve running speeds of approximately 25 km/h (15.5 mph).
As such, running may have been the most important way to escape predators.
Scientists also assume that Camptosaurus spent much time moving around its habitat.
It has also been suggested that, at times, it relied on a quadrupedal stance to feed on lower vegetation.
However, some scientists argue that Camptosaurus was fully quadrupedal, despite the popular belief that it walked only on its hind limbs.
The fully quadrupedal stance is supported by the fact that the front of the body was too massive to be supported only by the hind limbs.
As such, if Camptosaurus walked quadrupedally, the front of the body would be much lower, as the forelimbs were much shorter than the hind limbs.
Bipedal walking was likely more possible in juveniles than in adults.
Some sources mention that Camptosaurus may have been a social creature, but this behavior hasn’t been fully confirmed yet.
Unfortunately, little else is known about the behavior and lifestyle of Camptosaurus, and we can only hope that future paleontological discoveries will bring to light more fascinating details!
Life Cycle
Camptosaurus reproduced by laying eggs – like all dinosaurs, after all!
Paleontologists recovered from the Morrison Formation something called the remains of an advanced embryo, whereas eggshells were nowhere to be found.
The length of the embryo was estimated at 24 centimeters (9.44 inches).
This embryo is thought to have belonged to Camptosaurus and was likely altricial, meaning it was born quite undeveloped and required much parental care to survive and grow.
This is quite rare in the dinosaur world, as most newly hatched dinosaurs were precocial, meaning they could fend for themselves shortly after hatching.
Paleontologists discovered a nearly complete egg that was later associated with Camptosaurus.
It measured 110 x 55 millimeters (4.33 x 2.16 inches).
It has been suggested that young Camptosaurus could move bipedally much easier than adults, which indicates that their diet and lifestyle evolved and changed as they matured.
The other aspects of a Camptosaurus’ reproductive behavior and ontogeny are poorly studied.
We do not know what kind of nests it built and who built them, whether the adults incubated the eggs, or whether they indeed provided parental care.
If the young were altricial, we believe the parents remained with them until they were old enough to care for themselves.
But, in the end, who knows how things truly worked 150 million years ago?
After all, much of what is stated about our world’s prehistory is pure speculation.
But it doesn’t hurt to wonder, does it?
Evolution and History
Camptosaurus is part of the Ornithischia clade of dinosaurs.
Further down the taxonomic tree, it’s placed under Ornithopoda and Iguanodontia.
In Iguanodontia, this genus is classified under Ankylopollexia, a sister taxon to Dryosauridae.
It is believed that these two groups split approximately 157 million years ago due to differences in diversification and evolution.
Camptosaurus is believed to be the earliest member of Ankylopollexia, having evolved 155-156 million years ago.
Although its classification in the Dinosauria group is quite well established, the fossil identification posed several problems.
That’s why outlining a possible distribution and describing the dinosaur’s lifestyle and behavior is challenging.
Since the genus previously consisted of multiple fossils that were later reassigned to other genera, many of the characteristics attributed to Camptosaurus may be considered invalid if they were based on wrongly assigned material.
Let’s travel back in time to when the first Camptosaurus fossils were discovered.
We should arrive on September 4, 1879, in Albany County, Wyoming.
The Camptosaurus remains were found by William Harlow Reed and described by the end of the year by the famous Othniel Charles Marsh.
He named the genus Camptonotus, which translates to flexible back.
Marsh himself renamed the genus six years later, calling it Camptosaurus.
It turned out that Camptonotus had already been taken by a cricket.
Over the years, multiple specimens have been recovered, leading to the naming and description of several other species.
Subsequently, most of these fossils were reassigned to different genera, which is why you may find that Camptosaurus has multiple possible synonymous genera like Uteodon, Cumnoria, and Symphyrophus.
Today, the genus consists of three species – Camptosaurus dispar, Camptosaurus aphanoecetes, and Camptosaurus prestwichii.
However, only the type species (C. dispar) is fully recognized.
C. aphanoecetes, for example, is now considered synonymous with Uteodon.
The material was discovered at the Dinosaur National Monument.
C. prestwichii was discovered in Europe and initially assigned to Iguanodon prestwichii.
Later on, it was moved to Cumnoria and then to Camptosaurus.
Eventually, many scientists concluded that it should probably be reassigned back to Cumnoria.
In short, understanding how many specimens are associated with Camptosaurus is quite difficult.
Therefore, outlining a clear Camptosaurus evolution and history would yield a highly blurred image.
Interactions with Other Species
Outlining possible cohabitants of Camptosaurus is quite challenging, considering that scientists aren’t entirely sure of its distribution.
Since it has been fully confirmed that Camptosaurus lived in the territory we now call North America, we’ll focus on what creatures surrounded it there.
Obviously, we do not know how often these animals interacted with each other except for those that had a predator-prey relationship or those that competed for food.
The Morrison Formation is one of the richest fossil sites in North America, meaning that the territory was highly diverse in prehistoric animals.
Scientists discovered amphibian, sphendont, snake, lizard, turtle, crocodylomorph, pterosaur, and mammaliaform fossils.
Dinosaurs were abundant as well, especially herbivorous ornithischians, among which the Camptosaurus.
Others were Nanosaurus, Alcovasaurus, and Uteodon.
Dryosaurus and Stegosaurus were quite common as well.
The territory was probably dominated by sauropods like Diplodocus and Apatosaurus, which were among the world’s largest sauropods!
It remains unconfirmed whether Camptosaurus competed with these herbivores for food.
Studies show that Camptosaurus was excellent at chewing very tough vegetation, which was probably an advantage since this minimized competition for food among herbivores.
On the other hand, Camptosaurus and other herbivores were always on the lookout for carnivorous theropods like Ceratosaurus, Allosaurus, and Torvosaurus.
The largest in the territory was Saurphaganax, and it probably had no issues killing a Camptosaurus; that is if it caught it before it ran away!
Cultural Significance
The discovery of Camptosaurus marked a significant turning point in paleontology.
It is probably the oldest genus in the Ankylopollexia genus and an ancestor of the famous iguanodons and hadrosaurids.
As such, studying its appearance, lifestyle, and behavior is of utmost importance in outlining our world’s evolutionary history.
This herbivorous dinosaur makes frequent appearances in dinosaur handbooks as well, which only adds to its popularity.
On the other hand, unlike other dinosaurs, Camptosaurus is not a famous character in media productions.
It appeared only in Planet Dinosaur and in the video games Jurassic Park III: Park Builder and Path of Titans.
Hopefully, future media productions will reconstruct this fascinating dinosaur, which undoubtedly deserves our attention!
Conclusion
Camptosaurus lived in North America 156-146 million years ago, during the Late Jurassic.
It was a herbivorous ornithischian that likely fed on tough vegetation.
The beak and the teeth were of excellent help in cropping and chewing the plants.
Also known as the flexible lizard, Camptosaurus was quite large, reaching almost 7 meters (feet) in length and 800 kilograms (pounds) in weight.
Some scientists believe it preferred walking on the hind limbs, while others suggest that they wouldn’t be able to support the whole body weight and argue in favor of a quadrupedal lifestyle.
On the other hand, it may have been able to run fast, especially if a ferocious theropod hunted it!
FAQs
What are three interesting facts about Camptosaurus?
Here are three interesting facts about Camptosaurus:
- Camptosaurus was an inhabitant of North America, having lived in Wyoming, Utah, and possibly other regions. Scientists suspect it may have also lived in Europe, but this hasn’t been fully confirmed yet.
- Camptosaurus had a pointed snout, a beak, and tightly spaced teeth on the jaw, which helped it crop and chew tough vegetation.
Camptosaurus is an ancestor of iguanodonts and hadrosaurids.
Sources:
- https://en.wikipedia.org/wiki/Camptosaurus
- https://www.nps.gov/dino/learn/nature/camptosaurus-aphanoecetes.htm
- https://www.researchgate.net/publication/227739200_Palaeoclimate_of_the_Late_Jurassic_of_Portugal_comparison_with_the_Western_United_States
- https://www.google.com/books/edition/Dinosaur_Eggs_and_Babies/9BPIRx-OpRMC?hl=en&gbpv=1&dq=camptosaurus&pg=PA309&printsec=frontcover
- https://www.researchgate.net/profile/Peter-Galton/publication/285347338_Dryosaurus_and_Camptosaurus_intercontinental_genera_of_Upper_Jurassic_ornithopod_dinosaurs/links/57a6722c08ae455e85415174/Dryosaurus-and-Camptosaurus-intercontinental-genera-of-Upper-Jurassic-ornithopod-dinosaurs.pdf
- https://eastern.usu.edu/prehistoric-museum/exhibits/paleontology/camptosaurus
- https://go.gale.com/ps/i.do?id=GALE%7CA7512679&sid=googleScholar&v=2.1&it=r&linkaccess=abs&issn=00368075&p=AONE&sw=w&userGroupName=anon%7E6cce5086&aty=open-web-entry
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