Strange Diets

Scientists once thought that all big flesh-eating dinosaurs ate only large plant-eating dinosaurs. Then fossil hunters discovered the spinosaurs -a group of large flesh-eaters with jaws and teeth made to eat sizable fish. There may have been other groups of dinosaurs with specialized diets, too. For instance, wide-mouthed dinosaurs may have been unfussy browsers, whereas narrow-mouthed plant-eaters probably chose what they ate.

Suchomimus

Using its curved thumb claws as meat hooks, Suchomimus could have scooped up unsuspecting fish.

Using its curved thumb claws as meat hooks, Suchomimus could have scooped up unsuspecting fish.

Suchomimus's name, meaning "crocodile mimic," comes from its long slender skull.

With its mouth full, Suchomimus could still breathe, because its nostrils were behind the tip of its snout.

Out of africa

Fossil hunters discovered Suchomimus's remains in the Sahara in 1997. The team found the remains partly laid bare by desert winds, but removing the fossil bones still meant shifting 25 tons of rock and other material.

Suchomimus's name, meaning "crocodile mimic," comes from its long slender skull.

Suchomimus

This bizarre fish-eating dinosaur grew as large as Tyrannosaurus. It had a head like a crocodile's, longer arms than most meat-eaters, and enormous hindlegs. Behind its head, tall spinal bones supported a skin fin, or maybe a tall, narrow hump, which ran down its back. Suchomimus probably waded out into rivers and lakes, then stood or lay in the water to catch big fish with its jaws or clawed hands.

With its mouth full, Suchomimus could still breathe, because its nostrils were behind the tip of its snout.

Fossil finds Million years ago

strange diets

Baryonyx

Close cousins?

Suchomimus from Niger was closely related to Baryonyx, a fish-eating dinosaur from England. Suchomimus may have evolved from relatives of Baryonyx that migrated from Europe to Africa when both places were joined, although scientists now think it possible that Suchomimus was just a big Baryonyx.

Coelacanth

Coelacanth

Fish food

It would have taken fleshy fish up to 13 ft (4 m) long to satisfy Suchomimus's appetite. Possible victims included a kind of prehistoric lungfish, or a fish called Mawsonia. "Living fossil" relatives of Mawsonia, known as coelacanths, can still be found in the ocean off East Africa and Southeast Asia.

Friends or foes?

Today's crocodiles had prehistoric ancestors who lurked in the rivers where Suchomimus hunted. At 50 ft (15 m) long, the crocodilian Sarcosuchus was even larger than Suchomimus. Both kinds of reptile had narrow heads and slender, sharp teeth to cope with slippery prey. Sometimes, perhaps, dinosaur and crocodilian fought over a fish. The result would have been a bloodthirsty battle.

Crocodiles have changed very little since prehistoric times.

Crocodiles have changed very little since prehistoric times.

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DIVIDING THE SPOILS

Coelophysis was as long as a car but as light as an 8-year-old child. In the late Triassic, gangs of this bloodthirsty, birdlike dinosaur swarmed through semi-deserts and riverside forests, snapping up small game. Working together, a pack would have made light work of animals much larger than themselves. Prehistoric reptiles called aetosaurs were probably too well-armored to kill, but if a pack of Coelophysis found one dead, their sharp little teeth would have quickly reduced the corpse to a skeleton as they squabbled over the remains.

Nimble predator

Slim and agile, Coelophysis was built for darting after prey at speed. In many ways it was similar to long-legged water birds of today, such as storks and herons. Its narrow head, S-shaped neck, slender body, long legs, and hollow bones were much like a bird's.

So, too, were other features of its skeleton. But Coelophysis had a bony tail, clawed hands, not wings, and

■m sharp little teeth instead of a beak.

Triassic world

Coelophysis lived where dry months were followed by torrential rains. The largest plants were towering monkey-puzzle trees. Ferns, giant horsetails, and stubby, palmlike cycadophytes formed dense streamside thickets. These moister areas teemed with insects, lizards, dinosaurs, and lumbering aetosaurs. In streams lived fish, big amphibians called metoposaurs, and 10 ft (3 m) long crocodilelike phytosaurs - the largest freshwater predators of all.

Social life

Evidence that Coelophysis swarmed in packs comes from fossils of many individuals found piled up on one another in New Mexico. This dinosaur graveyard marks the spot where a shallow stream overflowed, drowning and then dumping hundreds of the slender, birdlike animals. Some scientists believe the larger specimens were males, while smaller, slimmer ones were females. Other scientists think Coelophysis females were larger than the males, as is the case among birds of prey today.

,.While others foraged for food, some members of the pack might have kept a lookout for predators, as meerkats do.

DIVIDING THE SPOILS

Animal cannibals

Tiny bones inside the ribcage of this fossil Coelophysis show that its last meal had been a baby Coelophysis. Several other adult Ceolophysis fossils have also been found containing the remains of youngsters they had swallowed. Perhaps adults turned into cannibals when other foods grew scarce. More likely, though, they always snapped up any creature small enough to swallow. Living reptiles, such as crocodiles, do the same.

Long, slender neck

, Bones of swallowed infant

Eye sockets

Two adults fight over , a scrap of meat.

Sharp teeth

Clawed foot

Long tail

Coelophysis

i triassic

jurassic

Fossil finds
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