How did Nigersaurus get its name?

The dunes of the Sahara Desert gave rise to a new and bizarre dinosaur. An elephant-sized creature with a skull and jaws, but unlike anything scientists have ever seen. That Dinosaur would go on to be called Nigersuarus.

It was given the nickname the “Mesozoic Cow”, as many paleontologists believe their behaviour was similar to that of modern cows.

Nigersaurus, pronounced as “NYE-jer-SORE-us” and derived from “Niger” (the nation where it was discovered) and the Greek “sauros” meaning lizard (making it “Niger’s lizard” or “Niger reptile”), was one of the oldest sauropodomorph herbivore dinosaurs ever discovered.

It’s a Diplodocus-like sauropod dinosaur genus. Nigersauraus had a relatively short neck and had an astonishing 500 teeth in it’s wide jaws, giving it very distinguished characteristics when compared to other dinosaurs.

When did Nigersaurus live?

Nigersaurus lived during the Cretaceous epoch and roamed Africa’s terrestrial areas. Its fossils have been discovered in countries like Niger, Africa, and it lived between the Aptian Age and about 100.5 -110 million years ago.

This period spans the Aptian to the Albian periods and even the Cenomanian. The African plains and woods were the dinosaur’s natural home. Nigersaurus tended to reside in places with adjacent water lakes or streams, known as the riparian zone. A riparian zone features a lot of low-lying vegetation due to the abundance of water. Nigersaurus was the only sauropod species that grazed, and experts believe it may have done almost continuously.

What did Nigersaurus eat?

With its shovel-shaped mouth, which contained over 500 teeth, it was perfectly equipped for eating large amounts of vegetation as it walked along. It is believed that Nigersaurus head would have almost been constantly at the ground, possibly devouring as much as a football field’s worth of vegetation in a single day.

Many paleontologists believe that Nigersaurus 500 teeth arrangement served much like a comb as well. Nigersaurus may have filtered and eaten water plants using a comb-like process to stop it from eating mud and dirt. However, some scientists believe it simply used its teeth to cut vegetation and then sucked it in using a vacuum-like motion due to the fragility of its jawbones.

Unfortunately, as the environment changed, various flora replaced the specialized grasses to which it had grown specifically adapted. Nigersaurus failed to adapt to its surroundings and eventually went extinct.

What Dinosaur family did Nigersaurus belong to?

The Nigersaurus belonged to several types of dinosaur including; the Sauropodomorpha suborder, Diplodocoidea superfamily, Rebbachisauridae family, and Nigersaurinae subfamily.

Nigersaurus was thought to be a member of the Dicraeosauridae family when it was discovered as its structure appeared to be similar to that of members of this particular family of dinosaur.

However, based on newly discovered fossil evidence, Paul Sereno reclassified the bones. The rebbachisaurids are the most primitive members of the Diplodocoidea superfamily, lacking the bifid neural spines found in the other species of dinosaur. Interestingly nigersaurinanians’ bones are hollow and filled with air.

What did Nigersaurus look like?

It took decades for scientists to notice this Nigersaurus peculiar appearance. Nigersaurus was given its official name in 1976, but it wasn’t until the late 2000s that palaeontologists had a good idea of what this particular dinosaur looked like.

This is due to the skeleton of this dinosaur being hollow in numerous areas, making it subject to breaking and distortion. Although specimens were plentiful before 1997, no substantial remains of Nigersaurus had been discovered, leading many to believe that Nigersaurus was just another ordinary sauropod.

Image source: Fandom

The dinosaur that has over 500 teeth

As discussed earlier, you may be visiting this page after searching for “What Dinosaur has 500 teeth?” If you have, let’s dive into more detail about Nigersaurs teeth.

The tooth row was not at all prognathous, and the snout tip did not protrude compared to the rest of the tooth series. The maxillary tooth row was transversely rotated in its entirety, with the posterior 90° everted towards the front.

This was mirrored by a similar rotation of the lower jaw’s dentary. As a result, no other tetrapod possessed all of its teeth as far forward as Nigersaurus did.

The crowns of the narrow teeth were slightly curved and oval in cross-section. The lower jaw teeth may have been 20–30 percent smaller than the upper jaw teeth. Aside from that, Nigersaurus’s teeth were the same.

Within the jaw, there was a column of nine replacement teeth under each active tooth. These so-called ‘dental batteries’ had a total of more than 500 active and replacement teeth, with 68 columns in the upper jaws and 60 columns in the lower jaws. The ‘dental batteries’ appeared in unison, not one by one. The enamel on Nigersaurus’ teeth was very asymmetrical, with the outer side being ten times thicker than the inner side.

The Dinosaur with 500 teeth

Nigersaurus had a large muzzle which contained all of its 500 teeth. Some scientists believe that these may have replaced every 14 days. The lower jaw of Nigersaurus was slightly S-shaped and separated into two sections.

The subcylindrical transverse ramus, which held the 500 teeth, and the rear ramus, which was lighter and housed the majority of the muscle attachments.

Several fenestrae were also found in the jaws, including three that were not found in other sauropods. Grooves on the front ends of the jaws indicated the existence of a keratinous sheath. The only known tetrapod with jaws broader than the skull and teeth that extended laterally across the front is Nigersaurus.

Image Source: Paul Sereno

Duckbilled shape mouths

The snout was even wider than the hadrosaurs with “duck-billed” snouts. One of the greatest pieces of evidence for determining how and what these sauropods ate is their teeth.

The teeth’s little facets and abrasions exhibit a pattern of micro-scratches and pits that depict what Nigersaurus ate.

This is turn of course wore the teeth down, and allowed scientists to gather evidence to make an informed decision based around Nigersaurus diet, which consisted of soft vegetation.

Nigersaurus skull

Nigersaurus’ original fossil skull was one of the first dinosaur skulls to be digitally rebuilt using CT scans. By using computed tomography to examine its skull, the researchers discovered something odd.

The scans revealed that Nigersaurus “organs of equilibrium,” which are similar to the semicircular canals in our own ears and help us maintain our balance.

It appears that Nigersaurus spent most of its time with its head practically straight down towards the ground, based on the arrangement of those organs. You might be thinking… ”That’s not how these enormous long-necked dinosaurs are normally portrayed?” And you’d be right! What this means for Nigersaurus is that it supports the notion that Nigersaurus was a ground-level grazer, and it would have used it’s 500 teeth like a lawn mower pulling in grass almost non-stop.

Paleontologists also believe that despite possessing enlarged nostrils, Nigersaurus olfactory lobes (which help the brain perceive scent) were significantly small, according to an examination of its brain cavity.

Nigersaurus had very unique skull features

The Nigersaurus’ skull was very unusual. Nigersaurus is the only tetrapod with jaws that are wider than the rest of its skull. Its bones were extremely fragile, and it had four more fenestrae (an opening in the skull that is in front of the eye sockets) than other sauropods.

A keratinous coating was most likely present near the ends of the jaws. The nasal apertures were enlarged and the mandible was S-shaped.

Despite the skull bine’s delicate character, it was sturdy enough to survive the repeated wear and tear of eating plants.

Image source By CaptMondo – Own work, CC BY-SA 3.0

The nickname “Mesozoic cow” was the name given to Nigersaurus because of its unique skull features, and it’s eating habits.

Unique skull features that Nigersaurus had included that there was only 1.0 cm2 of bone connecting the muzzle to the back of the skull (0.16 sq. in). These bone connecting struts were often less than 2 mm (0.08 in) thick.

A closed supratemporal fenestra was another distinguishing feature among sauropodomorphs. Though the exact location of the nasal bones is unknown, the front margin of the bony nostril appears to be closer to the snout than in other diplodocoids.

How big was Nigersaurus?

Nigersaurus was a quadruped with a tiny skull, thick hind legs, and a prominent tail, as were nearly all sauropods.

Nigersaurus was a miniscule member of that group, with a body length of only 9m-10m (30ft) and a femur of only 1m. (3ft 3 in).

Nigersaurus weighed around 4 tonnes  (4.4 short tons), which is a similar weight to a modern elephant.

With thirteen cervical vertebrae, it had a short neck for a sauropod. Its skull had some unusually thin cranial bones, some of which are virtually translucent.

For a Sauropod, Nigersaurus had a very peculiar mouth. Nigersaurus had a large intake (wider than the rest of its skull), and after getting food into its mouth, Nigersaurus would have used its 500 teeth to chew up its food.

Though adults Nigersaurus could reach up to 30ft in length, a hatchling Nigersaurus’s jawbone was so small that it could “fit on top of a silver dollar,” according to paleontologists.

Nigersaurus fossilised remains.

Nigersaurus remains have caused the scientific community some frustration as the bones were very thin and pneumatic. So much so that one of the Nigersaurus skull remains was so thin that sunlight could pass right through it.

The fragile condition of the bones was the reason for their poor preservation. The good news is that almost all bones of the Nigersaurus have been discovered, except for a few rib bones and coccygeal vertebrae.

A detailed article about Nigersaurus’ look was published in 2005. The author of that article described its unique Skull, which contained 500 teeth, as well as its eating adaptations.

A more detailed report on the entire Nigersaurus skeleton was published in 2007. Many fossils unearthed by other palaeontologists are still being examined, and more information will become available as the research progresses.

Further reading and study on Nigersaurus:

• Sereno and Beck (1999). Cretaceous sauropods from the Sahara and the uneven rate of skeletal evolution among dinosaurs.
• Sereno et al., (2007) Structural Extremes in a Cretaceous Dinosaur
• Wilson et al., (2005). Structure and evolution of a sauropod tooth battery.
• Ross-Flanigan (2007). U-M researchers study toothy, ground-feeding dinosaur
• Joyce. (2013). Mesozoic Cow‘ Rises from the Sahara Desert
• Robert W. Bernard, MD, Aesthetic Surgery Practice: Another Nigersaurus?