10 Sail-Backed Facts About Ouranosaurus


If you could somehow take an African safari 125 million years ago, seeing Niger’s gorgeous Ouranosaurus in the flesh would be a real Kodak moment.

1. In Certain Places, Its Stunning Sail Was Almost Two Feet Tall.   

Jargon time! “Neural spines” is the technical term for those long attachments sprouting from Ouranosaurus’ backbones. Together, they (probably) formed a slender, fin-like accessory whose unknown purpose has scientists scratching their heads. The ornate sail is often viewed as a makeshift solar panel—in theory, blood was warmed or cooled there, and then redistributed throughout Ouranosaurus’ body to keep its temperature under control. That explanation may sound logical, but there’s no evidence of especially large or numerous blood vessels around these structures.

2. Ouranosaurus Came With High Nostrils.

Pavel Riha, via Wikimedia Commons// CC BY-SA 3.0

In this portrait’s upper left-hand corner, a disembodied Ouranosaurus head hovers. As you can see, the forest green animal has nasal openings that are relatively far away from the tip of its beak. Because the dino frequented river deltas, these strategically-placed nostrils may have helped it dine on low-lying plants in peace without inhaling mud by mistake.  

3. A Similar-Looking Dinosaur has Shown Up in South America.

Northeastern Brazil yielded some very Ouranosaurus-esque tail vertebrae during the early 2000s.

4. The Creature’s Name Means Something You Might Not Expect.

Nearly 40 years ago, paleontologist Philippe Taquet proudly presented his newly-discovered Ouranosaurus to the world. Its scientific moniker roughly translates to “brave lizard” and was—he says—partially “taken from the Arab word ourane, which signifies ‘valiant, courageous, bold.’” Incidentally, “ourane” is also a name by which some Nigerian nomads refer to local monitor lizards.  

5. We Only Have Two Skeletons to Work With.

Luckily, between them, experts have recovered the majority of Ouranosaurus’ bones (which is fairly rare for larger dinos like this 27-footer), including a complete skull.

6. Some Say that Ouranosaurus Was Built Like a Bison.

Sampsonchen, WikimediaCommons // CC BY-SA 3.0

“The Hump-Backed Dinosaur” sure has a nice ring to it. As Dr. Jack Bowman Bailey of Western Illinois University pointed out in 1997, Ouranosaurus' neural spines look similar to a modern bison’s. Maybe paleontologists were wrong to assume that this animal had some skinny, board-like sail. Instead, Bailey envisioned Ouranosaurus taking after its mammalian counterpart, with thick muscle and pockets of fat anchored to the specialized bones.

Today, his idea has attracted a few supporters in paleontological circles. But many more cast doubt on Bailey’s conclusion. First of all, bison primarily use their abundant back fat as a means to survive cold, dry seasons. But Ouranosaurus’ environment was chronically lush and swampy, so fatty reserves wouldn’t have been needed—or, at least, that's what the critics of his theory say. Also, while much of the muscle connected to bison humps supports their hefty heads, Ouranosaurus noggins were proportionally no larger than those seen in similar, sail/hump-free dinos.

7. Ouranosaurus Also Had Two Odd, Triangular Bumps In Front Of Its Eyes.

Function-wise, these seem suited for social tasks like attracting mates. They’re aesthetically pretty tame by dinosaur headgear standards—get a load of this guy!

8. There’s a Common Misconception that It Lived Alongside Another, More Famous Sail-Back.

Ouranosaurus and the predatory Spinosaurus aegyptiacus are frequently seen sharing their environment in dino books and TV documentaries, even though they were actually separated by a few million years. Also, they’ve never been found in the same deposits.

9. It Wielded a Pair of Rather Dinky “Thumb Spikes.”

Ballista, via Wikimedia Commons // CC BY-SA 3.0

Were these handy weapons? Nut-cracking tools? Tree bark-removers? Paleontologists aren’t certain. Like Europe’s iconic Iguanodon, Ouranosaurus possessed a conical spike on each hand, though the African dino’s were significantly smaller.

10. An Ouranosaurus Once Received a Strange, Patriotic Ceremony.

According to Taquet’s wonderful memoir, Dinosaur Impressions: Postcards from a Paleontologist, the first Ouranosaurus specimen ever unearthed “was placed in the National Museum of Niger in Niamey, inaugurated by the president of the National Assembly of that country, Boubou Hama. A small Niger girl, very timid and cute, with her plaited braids, dressed like an ouranosaur in silk colored like the Niger flag, presented the president with a pair of scissors to cut the ribbon across the entry door.”