Dinosaurs roamed the Earth millions of years ago, but what we know about them and how they lived is still evolving.
Take the long-extinct Spinosaurus, for example. Though this dinosaur was once nearly lost to history, in recent years scientists have unearthed exciting findings: Not only was the Spinosaurus larger than the mighty T. rex, but it is also the first dinosaur known to dwell in water.
Fossils—preserved remains of bones, teeth, and other parts of an organism—are what gave us these new insights.
In 2015, researchers Paul Sereno and Nizar Ibrahim brought a life-size skeletal replica of the Spinosaurus to National Geographic headquarters in Washington, D.C., to be the centerpiece of the National Geographic Museum exhibition.
In 1912, a partial Spinosaurus skeleton was first identified by a German paleontologist during his expeditions to the Sahara in Egypt. Those fossils were later put on display at a museum in Munich, Germany. During World War II in the 1940s, bombing demolished the museum and its many treasures, including the skeleton. The only known Spinosaurus bones were lost.
Fast-forward to 2008, when new Spinosaurus fossils were found in the Moroccan Sahara along desert cliffs known as the Kem Kem beds. It turned out that these bones matched a partial Spinosaurus skeleton that had recently turned up at the Natural History Museum in Milan, Italy. All of these bones belonged to the same dinosaur.
In 2013, Paul Sereno, head of the University of Chicago’s Fossil Lab, and Nizar Ibrahim, a 2014 National Geographic Emerging Explorer, worked with an international team of researchers to analyze these fossils and create a computer model of the dinosaur’s entire skeleton. Then the scientists used a 3-D printer to produce a replica of each bone, and these artificial remains were assembled into the life-size model.
By studying the dino duplicate, the team confirmed that Spinosaurus grew to approximately 50 feet in length, nearly 10 feet longer than the largest T.Rex specimen. The scientists also noticed that Spinosaurus had odd features not seen in other dinosaurs, such as feet that may have been webbed and a crocodile-like snout. Sereno, Ibrahim, and the other researchers realized that these traits would help the predator survive in water and came to the surprising conclusion that Spinosaurus was semi-aquatic.
Some researchers were not convinced that the Spinosaurus would have been a very good swimmer, though, due to the awkward shape of its body. There weren’t enough fossils to know for sure.
Now that has all changed once again. In 2018, Ibrahim took a team of researchers to Morocco to dig up even more Spinosaurus fossils. The National Geographic-funded expedition led to an astonishing revelation: the Spinosaurus had a sail on its back that seems to have run all the way down its tail, which experts believe would have helped propel it through water.
There’s still much more to discover. As the researchers continue to study Spinosaurus and its fossils, you can expect this water-dwelling dino to make more waves.