The first bones came in a cardboard box. Nizar Ibrahim, a paleontologist, was in the Moroccan oasis town of Erfoud at the edge of the Sahara, returning from a dinosaur dig in the sands. Inside the box, brought to him by a nomad, were sediment-encrusted pieces more intriguing than anything he had found himself, including a blade-shaped bone with a reddish streak running through the cross section. He took the bones to a university in Casablanca.
The next year, he was in Italy visiting colleagues at the Milan Natural History Museum who showed him bones that seemed to be from Spinosaurus aegyptiacus, a strange-looking predatory dinosaur larger than Tyrannosaurus rex that lived in northern Africa about 95 million years ago.
He looked at the spines, part of a giant distinctive sail on the back of Spinosaurus. He saw a familiar red line — possibly a passageway for blood vessels long since decayed away — in the cross section of a bone. “My mind started racing,” he said.
Photo
An artist's interpretation of how Spinosaurus aegyptiacus might have looked and how its size might have compared with that of a human. CreditDavide Bonadonna
Amazingly, the pieces in Milan and those he had seen a year earlier and 1,200 miles away were from the same ancient skeleton.
That was the start of an odyssey of diligence and serendipity that led to the unveiling on Thursday of a new skeleton of Spinosaurus. The largest known predatory dinosaur, growing to at least 50 feet in length, Spinosaurus is also the only dinosaur known to be a swimmer that spent a large fraction of its life in the water.
“It’s probably the most bizarre dinosaur out there,” said Dr. Ibrahim, a graduate student when he saw the first bones, and now a postdoctoral researcher at the University of Chicago.
Spinosaurus had been an intriguing mystery for decades. The original fossil of the dinosaur, discovered in Egypt a century ago and moved to a German museum, was destroyed during World War II, leaving paleontologists with little more than a few drawings to ponder.
The new partial skeleton is of a Spinosaurus not fully grown, about 36 feet long. Its forelimbs were large and strong, with scythe-like claws; its hind legs were short, with paddle-shaped feet.
In an article published online on Thursday by the journal Science, Dr. Ibrahim and an international team of colleagues describe the features that made the dinosaur well suited for swimming and feasting on giant fish that lived in the rivers there.
Conical teeth in a crocodilian snout overlapped like a snare for trapping fish, and it had nostrils halfway up the skull so it could stick its snout into the water and still breathe.
With its flat feet, Spinosaurus may have paddled like a duck. It had a long, flexible tail, which it may have used for propulsion. “It’s like a cross between an aquatic bird and a crocodile,”
said Paul C. Sereno, a paleontologist at the University of Chicago who was part of the research team.
On land, Spinosaurus was ungainly. The researchers calculated that its center of mass would have been too far forward for it to have stood easily on its hind legs, like other predator dinosaurs; instead, it ambled on all four legs.
“It does add significantly to the strangeness,” said Matthew C. Lamanna, a paleontologist at the Carnegie Museum of Natural History in Pittsburgh, who was not involved with the research. He described the evidence for Spinosaurus’s semiaquatic existence as “quite convincing.”
Photo
A life-size model of Spinosaurus aegyptiacus made from polystyrene, resin and steel. The model was created from computer scans of fossils, images of lost bones and educated guesses using bones from related dinosaurs. CreditMike Hettwer/National Geographic
An exhibition on Spinosaurus opens Friday at the National Geographic Museum in Washington. The National Geographic Society provided financing for the research.
The new findings may return prominence to Ernst Stromer, the German paleontologist who first described Spinosaurus aegyptiacus, meaning “Egyptian spine lizard.”
Stromer’s fossil, mounted in the Bavarian State Collection of Paleontology in Munich, included the lower jaw and parts of the spine.
In April 1944, the British Royal Air Force dropped a bomb on the museum, and Spinosaurus — and every Egyptian dinosaur fossil known at the time — burned.
After that, some isolated bones of Spinosaurus were found, but nothing as complete as Stromer’s specimen. Some evidence, like the conical teeth, suggested Spinosaurus ate fish, but perhaps it just waded into a river and caught them like a grizzly bear.
The next year, he was in Italy visiting colleagues at the Milan Natural History Museum who showed him bones that seemed to be from Spinosaurus aegyptiacus, a strange-looking predatory dinosaur larger than Tyrannosaurus rex that lived in northern Africa about 95 million years ago.
He looked at the spines, part of a giant distinctive sail on the back of Spinosaurus. He saw a familiar red line — possibly a passageway for blood vessels long since decayed away — in the cross section of a bone. “My mind started racing,” he said.
Photo
An artist's interpretation of how Spinosaurus aegyptiacus might have looked and how its size might have compared with that of a human. CreditDavide Bonadonna
Amazingly, the pieces in Milan and those he had seen a year earlier and 1,200 miles away were from the same ancient skeleton.
That was the start of an odyssey of diligence and serendipity that led to the unveiling on Thursday of a new skeleton of Spinosaurus. The largest known predatory dinosaur, growing to at least 50 feet in length, Spinosaurus is also the only dinosaur known to be a swimmer that spent a large fraction of its life in the water.
“It’s probably the most bizarre dinosaur out there,” said Dr. Ibrahim, a graduate student when he saw the first bones, and now a postdoctoral researcher at the University of Chicago.
Spinosaurus had been an intriguing mystery for decades. The original fossil of the dinosaur, discovered in Egypt a century ago and moved to a German museum, was destroyed during World War II, leaving paleontologists with little more than a few drawings to ponder.
The new partial skeleton is of a Spinosaurus not fully grown, about 36 feet long. Its forelimbs were large and strong, with scythe-like claws; its hind legs were short, with paddle-shaped feet.
In an article published online on Thursday by the journal Science, Dr. Ibrahim and an international team of colleagues describe the features that made the dinosaur well suited for swimming and feasting on giant fish that lived in the rivers there.
Conical teeth in a crocodilian snout overlapped like a snare for trapping fish, and it had nostrils halfway up the skull so it could stick its snout into the water and still breathe.
With its flat feet, Spinosaurus may have paddled like a duck. It had a long, flexible tail, which it may have used for propulsion. “It’s like a cross between an aquatic bird and a crocodile,” said Paul C. Sereno, a paleontologist at the University of Chicago who was part of the research team.On land, Spinosaurus was ungainly. The researchers calculated that its center of mass would have been too far forward for it to have stood easily on its hind legs, like other predator dinosaurs; instead, it ambled on all four legs.
“It does add significantly to the strangeness,” said Matthew C. Lamanna, a paleontologist at the Carnegie Museum of Natural History in Pittsburgh, who was not involved with the research. He described the evidence for Spinosaurus’s semiaquatic existence as “quite convincing.”
Photo
A life-size model of Spinosaurus aegyptiacus made from polystyrene, resin and steel. The model was created from computer scans of fossils, images of lost bones and educated guesses using bones from related dinosaurs. CreditMike Hettwer/National Geographic
An exhibition on Spinosaurus opens Friday at the National Geographic Museum in Washington. The National Geographic Society provided financing for the research.
The new findings may return prominence to Ernst Stromer, the German paleontologist who first described Spinosaurus aegyptiacus, meaning “Egyptian spine lizard.”
Stromer’s fossil, mounted in the Bavarian State Collection of Paleontology in Munich, included the lower jaw and parts of the spine.
In April 1944, the British Royal Air Force dropped a bomb on the museum, and Spinosaurus — and every Egyptian dinosaur fossil known at the time — burned.
After that, some isolated bones of Spinosaurus were found, but nothing as complete as Stromer’s specimen. Some evidence, like the conical teeth, suggested Spinosaurus ate fish, but perhaps it just waded into a river and caught them like a grizzly bear.
An artist's interpretation of how Spinosaurus aegyptiacus might have looked and how its size might have compared with that of a human.
Davide Bonadonna
One fossil, uncovered in Morocco around 1975, had been thought to be part of the lower jaw of a crocodile, but a decade ago, Cristiano Dal Sasso of the Milan museum realized that interpretation was upside down. “There were too many bones to be the lower jaw,” he said.
It was actually from the top half of a snout of a huge adult Spinosaurus.
In 2008, an Italian geologist showed the new Spinosaurus bones to Dr. Dal Sasso, who then showed them to Dr. Ibrahim.
But the scientists were missing crucial geological information about where the bones had been excavated.
Dr. Ibrahim needed to find the nomad, so last year, he returned to the Erfoud area.
A life-size model of Spinosaurus aegyptiacus made from polystyrene, resin and steel. The model was created from computer scans of fossils, images of lost bones and educated guesses using bones from related dinosaurs.
Mike Hettwer/National Geographic
