| Name | Ouranosaurus | Diet | Herbivorous |
| Name Meaning | Brave Lizard | Height | 3 meters (9.8 feet) |
| Pronunciation | Or-an-o-sor-us | Length | 7-8.3 meters (23-27 feet) |
| Era | Mesozoic–Early Cretaceous | Weight | 2.2 metric tons (2.4 short tons) |
| Classification | Dinosauria, Ornithischia & Ornithopoda | Location | Niger(Africa) |
Ouranosaurus Pictures
The Ouranosaurus
Living during the Early Cretaceous period from the Aptian to the Albian stages, the Ouranosaurus is a large Hadrosauriform dinosaur that once inhabited Niger Africa.
The first remains of this dinosaur was discovered in 1965, and it was only until a decade later this dinosaur was named.
Its genus name translates to the brave, or courageous lizard, with the only species Ouranosaurus nigeriensis referencing where this dinosaur was discovered.
Since their discovery a lot has been learned about the Ouranosaurus, and this article will cover some of interesting facts about them including what they ate, the plants and animals they lived with, and what role this dinosaur played in its environment.
Ouranosaurus lived around 93.9 to 125 million years ago, and there is still much to learn about this ancient hadrosauriform that lived in Africa.
Physical Characteristics
Ouranosaurus is a large species of iguanodontian, that had a length between 7 to 8.3 meters (23 to 27 ft.) long.
These dinosaurs walked on all fours, with their back legs being sturdier than their front.
Ouranosaurus feet had a claw for the thumb, hoof-like toes, and ankles that were fused to support their large weight.
Their stronger back legs helped support their large body weight, but also could have been used to help them stand on two legs.
The leg structure and feet suggest these animals were adept at walking, but it is not believed they had the ability to sprint due to their body structure.
The bodies of Ouranosaurus were extremely robust, and these dinosaurs weighed up to 2.2 tonnes (2.4 short tons).
The tail of Ouranosaurus was extremely long, and their heads were small, along with their neck when compared with the rest of their body.
Ouranosaurus had one of the longest skulls of any dinosaurs that was not a hadrosaurid, with a length around 67 cm (26.4 in.), a width around 24.4 cm(9.6 in.), and a height of only 26 cm tall (10.2 in).
On its back Ouranosaurus had a large sail, supported by neural spines that run up to the rear of its tail, similar to dinosaurs like the Spinosaurus.
The elongated head, large sail, and massive size is what makes these dinosaurs stand out from other similar hadrosauriformes.
Habitat and Distribution
The Ouranosaurus lived during the Early Cretaceous period around 93.9 to 125 million years ago, and inhabited what is now Africa.
These dinosaurs were discovered in the Gadoufaoua region in Niger within the Sahara Desert.
Ouranosaurus was discovered in the Elrhaz Formation, which dates to the Aptian stage of the Cretaceous.
In the Cretaceous period Africa was finally separated from South America, and dinosaurs in their own environment began to evolve to have their own traits to become unique to the region they lived in.
Due to the little fossil evidence of Ouranosaurus it is now known how large the range these dinosaurs stretched, and they are only known to live in what is now the region of Niger.
Where Ouranosaurus lived during the early Cretaceous Niger was dominated by inland floodplains, and the environment was very wet, with lots of plants.
Today Gadoufaoua is extremely dry, and arid, but during the Early Cretaceous the land was filled with trees, plants, and rivers.
The wet environment also helped create some of the fossils found today, as the drying rivers allowed fossils to form.
Behavior and Diet
Ouranosaurus was a herbivorous dinosaur that fed on plants like leaves, fruit, seeds, and other thick vegetation.
This dinosaur had a beak-like mouth, similar to hadrosaurids.
The mouths of these dinosaurs are very wide, and they have several teeth similar to dinosaurs like Iguanodon which help them chew their food.
The Ouranosaurus back of the skull was very narrow, with very little places for muscle attachments to be placed.
The very few places in the Ouranosaurus skull for muscles, suggested these dinosaurs had a very weak bite force.
It is common for dinosaurs that are herbivorous like the Stegosaurus to have a very weak bite force, and these dinosaurs typically only eat softer vegetation.
Herbivorous dinosaurs with a stronger bite force usually get this way since they live in environments with lots of thick vegetation.
The river delta habitat where Ouranosaurus lived was likely filled with lots of soft vegetation, and these dinosaurs evolved to have large mouths to feed in bulk.
Ouranosaurus had lots of teeth used for grinding their food, making it easier for them to digest.
The nostrils of these dinosaurs were very high on their head, which helped them breath, and less likely to get blocked by things like dirt when eating.
Life Cycle
The life cycle of Ouranosaurus is relatively unknown, since there have not been many fossils discovered of these dinosaurs.
Typically when paleontologists study the life cycle and growth of dinosaurs they use multiple fossils from different ages to find their growth rate.
Dinosaurs like Ouranosaurus likely started from eggs, but it is not known whether these dinosaurs cared for their young similar to other dinosaurs like the Oviraptoridae family.
When young these dinosaurs were very vulnerable to large predators, and they were likely prey for many of the large carnivores they lived with.
The lifespan of Ouranosaurus is currently unknown, but with more fossils there are still lots that can be discovered about this dinosaur.
While it is not known how common these dinosaurs were, they were an important part of the circle of life in their environments, and were used as prey for the other dinosaurs they lived with.
Evolution and History
The Ouranosaurus was discovered on an expedition led by French paleontologists that occurred from 1965 to 1972.
These dinosaurs were discovered in the upper layer of the Elrhaz Formation, which is located in Niger Africa.
On the first expedition around 8 specimens of Iguanodontian were discovered, and they were brought back to the Museum National d’Histoire Naturelle in Paris in 1967.
There were two nearly complete specimens found in the Niger that led to the creation of the species Ouranosaurus nigeriensis in 1967.
The genus name Ouranosaurus means “bravery lizard”, “recklessness lizard”, or “valor lizard”, and translates from that in Arabic, with their species name referencing Niger, where they were discovered.
There is currently only one species of Ouranosaurus, and this genus is represented by two nearly complete fossils, and three other fragmented specimens.
Originally when described Ouranosaurus was placed into the Iguanodontidae family, since they had similar traits to those dinosaurs like their spiked thumb, and body shape.
This dinosaur was later classified into the Hadrosauriformes clade, which is closely related to the hadrosauridae family.
Ouranosaurus are an early representation of hadrosauriformes, and are an example of convergent evolution, since they evolved to have similar traits to hadrosaurids.
In 2010 Andrew McDonald and his colleagues were the ones who analyzed where this dinosaur fit in the Iguanodontia cladogram.
How this dinosaur is classified, and what relatives they are closest to may change if further analysis is done, and more fossils are discovered.
Interactions with Other Species
When a juvenile Ouranosaurus would have been at its most vulnerable, and their large size would have been their best defenses.
Ouranosaurus is one of the largest herbivorous dinosaurs in Niger, and lived alongside predators like spinosaurids.
Spinosaurids like Suchomimus and Baryonyx likely preyed on smaller Ouranosaurus, even though these dinosaurs are thought to mainly eat fish.
Other large theropods like Carcharodontosaurus, and ancient crocodiles like Sarcosuchus also could have eaten these herbivores.
The bite force of Ouranosaurus was also very weak, and compared to other dinosaurs Ouranosaurus did not have many defenses like horns, or frills.
They relied on their size to defend themselves, and it is not known if these dinosaurs lived in herds, but that also would have helped them survive.
In the river delta habitats Ouranosaurus would have been one of the largest meals to find, and these dinosaurs likely played a key role in their ecosystem as food for the giants they lived with.
Cultural Significance
In Niger Africa Ouranosaurus is one of the several species that represent the life that lived in those lands during the Cretacoeus period.
Only a few dinosaurs have been discovered that inhabited Niger, but each of these discoveries have been important in learning about the prehistoric ecosystem in the region.
Ouranosaurus has been showcased in several dinosaur games, including some of the most popular series like Jurassic Park.
Dinosaurs from Africa have been very popular since some that lived in the area were the most ferocious and largest.
The predators that Ouranosaurus lived alongside with, and the nearly complete fossils found is why these dinosaurs have been popular herbivores depicted in media.
Ouranosaurus also helped give scientists insight into how earlier herbivores looked during the Cretaceous period.
The Iguanodontidae family has been changed over time, with lots of genus being discovered.
The Ouranosaurus has helped better understand how Iguanodontidaes evolved, and what dinosaurs lived in Niger.
Conclusion
Ouranosaurus is one of the many dinosaurs that lived in Africa, and lived around 93.9 to 125 million years ago.
These dinosaurs represent some of the earlier herbivores that lived during the Cretacoeus, and help showcase how dinosaurs evolved overtime.
Despite their lack of overall fossils compared to other dinosaurs, the very well preserved specimens have allowed scientists to learn alot about this ancient species.
Ouranosaurus was a herbivore adapted to feed on softer vegetation, and due to their lack of defenses they were likely preyed on by a myriad of large predators they lived with.
Living in one of the most dangerous times on earth, Ouranosaurus lived alongside some superpredators like Suchomimus, and giant extinct crocodilians.
There is still lots to learn about Ouranosaurus, and in the future there may be more fossils of this specimen discovered that give more insight into these lesser known dinosaurs.
FAQS
What was the sail of Ouranosaurus used for?
Paleontologists believe that the sail of Ouranosaurus could have been used for thermoregulation, or was just for display.
It is also possible these sails could have worked similar to animals like bison or camels, which store things like fat to preserve energy, but more studies are needed to confirm their use.
Did Ouranosaurus have horns?
The Ouranosaurus has small rounded horns in front of its eyes, and compared with other dinosaurs with horns these are very small.
This trait is very rare for dinosaurs like Ouranosaurus, and they are one of the only known ornithopods with this trait.
When did Ouranosaurus go extinct?
The Ouranosaurus dates from the Aptian age, and it is believed these dinosaurs went extinct at the Albian age during the Cretaceous period.
It is not known why these dinosaurs went extinct, but they likely went extinct during the middle Cretaceous due to other dinosaurs evolving, or a change in environment.
Sources:
- https://books.google.com/books?hl=en&lr=&id=9bt-sjA-kb0C&oi=fnd&pg=PA283&dq=Ouranosaurus+&ots=SsGOnPnQTp&sig=KGIyHBv0FLUjK0ImPrO2rlPnAXo#v=onepage&q=Ouranosaurus&f=false
- https://en.wikipedia.org/wiki/Ankylopollexia
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5480399/
- https://en.wikipedia.org/wiki/Category:Cretaceous_Niger
- https://www.nigerheritage.org/dinosaurs
- https://www.researchgate.net/figure/MSNVE-3714-Ouranosaurus-nigeriensis-The-mounted-specimen-as-exhibited-today-at-the_fig1_317741451
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