Life in Water Ibrahim imagines Spinosaurus hunting like a modern-day bird, the heron. He pictures it leaning forward and snapping up fish in its muzzle. Its crocodile-like jaws could remain open to snap up underwater meals. Its large, cone-shape teeth gripped slippery fish. Its massive, curved front claws tore food. Because Spinosaurus lived in water, it


didn’t have to compete with other giant dinosaurs for food. T at supports Ibrahim’s hypothesis that Spinosaurus lived with other large predators.


Spinosaurus’ wide, back feet may have been webbed.


Questions Remain Ibrahim is still puzzled by the sail, though. Some scientists think it regulated the dinosaur’s body temperature. Blood in the sail could soak up the sun’s heat, they say. Yet when Ibrahim looks at the evidence, he


has a diff erent hypothesis. T e spines are thin and have few channels for blood vessels. Instead, Ibrahim thinks Spinosaurus used


Making a Model T e Spinosaurus’ neck and body were longer than other dinosaurs’. T e Spinosaurus had short hind legs and powerful forearms. Its back feet were wide and flat. To Ibrahim, they looked like paddles. Ibrahim studied Spinosaurus’ skull closely.


It had a long snout, but its nostrils were halfway up the skull. And then there was the sail. It was about 1.8 m long and rose more than 1.8 m from its back. Until Ibrahim had created this model,


scientists had assumed that Spinosaurus spent most of its time on land. Seeing the way this dinosaur actually looked made Ibrahim realize that it probably didn’t spend much time there. Ibrahim made a conclusion that this


dinosaur spent most of its time in water. Its long tail may have helped propel it through the water. Spinosaurus probably had webbed feet that it used to paddle through rivers. High nostrils allowed it to keep most of its head underwater while it hunted.


22 NATIONAL GEOGRAPHIC EXPLORER


its sail as a warning sign. A sail that large would have stuck out of the water when Spinosaurus was hunting. Other dinosaurs would know to stay away from this predator. Ibrahim continues to dig to find answers


to his Spinosaurus questions. For now, one thing appears clear—the more impossible the questions seem, the more determined Ibrahim is to find the answers.


conclusion: an opinion formed after careful research and thinking


experiment: a test used to fi nd or prove something


hypothesis: an idea that has not been proved


method: a step-by-step plan to fi nd out if an idea is true or not


observe: to gather information by looking at something closely

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