With the discovery of fossils great and small, scientists continue to break new ground in their quest to understand the amazing creatures that roamed our planet millions of years ago. And there's more to come—it's estimated that less than one percent of all dinosaur species have been discovered.
Prehistoric Horrors
The largest meat-eater
Found in the desert of Patagonia, this creature is the largest meat-eater ever discovered. It is even longer than the 41-foot-long Gigantosaurus and the 40-foot-long Tyrannosaurus rex. This as-yet-unnamed giant probably looked a lot like T. rex but with a pointy, scissorslike jaw. "I think it would have been terrifying," said one of the excavators. A number of these massive meat-eaters—both adults and youngsters—were found together, possibly drowned. The grouping was a surprise to scientists who had thought that meat-eating dinosaurs traveled alone. They now wonder if the dangerous carnivores in fact hunted as a pack, ganging up on much larger plant-eaters.
Our Tiniest Ancestor
The smallest primate
Its foot bones are the size of grains of rice, and it weighs less than a dozen paperclips. Yet the miniature "Dawn Monkey" could represent an evolutionary link between lower primates and higher primates, a group that includes apes and humans. The structure of its tiny ankle bones suggest that it could walk flat footed, using all four legs, like advanced primates. Unlike advanced primates, however, it probably "didn't have a lot of time to be social," guesses one scientist. That's because the little animal had to spend most of its time eating to feed its high-speed metabolism—when it wasn't trying to avoid being eaten by bigger creatures. The discovery of this specimen in Asia suggests that our earliest ancestors did not live in Africa alone, as previously thought.
A Giant Vegetarian
The longest of them all
In a remote desert area of Argentina, a villager found the remains of what is believed to be the world's longest dinosaur. Like Brontosaurus and other plant-eating dinosaurs, this giant creature probably had a small head and a very long neck and tail. But it is at least 25 feet longer than Seismosaurus, which was previously believed to be the largest dinosaur. The lonely region where it was discovered has turned out to be a hotbed of dinosaur fossils. "In Patagonia, walking among the rocks is enough to discover fossils," says a researcher in the area. As they discover ever-larger dinosaurs, it gets harder for scientists to name each massive beast—unfortunately for this unnamed hulker, Gigantosaurus, Supersaurus, and Ultrasaurus are already taken.
Careful Feeding this Baby
The most complete young T. Rex
This baby Tyrannosaurus rex, a male, was probably one-quarter the size of its parents, and was still young enough that its spine was not fully developed. Like other youngsters, it had long, gangly legs. But even as a baby it had the bone-crushing jaws of an adult. This suggests that even though a Kid Rex would not have been strong enough to tackle large prey, it ate an adult diet supplied by its parents. This 66-million-year-old baby, nicknamed "Tinker," died with half a duck-billed Platypus in his belly. With a skeleton that could be 90 percent complete, researchers hope to gain new understanding of the T. rex's life cycle. "You're getting a window into the childhood of the world's favorite dinosaur," says one paleontologist. It wasn't an easy childhood—this youngster appears to have been chewed up by a larger dinosaur, perhaps a confused parent.
Old Folks
The earliest dinosaurs
Jawbones of the two oldest dinosaurs ever found were discovered by a boy on the African island of Madagascar. These prosauropods (early plant-eaters) are estimated to be 230 million years old. Because scientists know so little about that era—when not only dinosaurs but mammals developed—they hope the find will help them to unravel the mysteries of dinosaur evolution. The two plant-eaters are about the size of young cows and probably used their front legs to rummage through plants on the ground, though they could also run on all four legs. Over the next ten or so million years, these little creatures evolved into the huge sauropods we think of when we hear the word dinosaur. "How they got so big so fast is an interesting question," said a scientist working on the find.
| Unnamed Carnivore Weight: 18,000 pounds Length: 45 feet Age: 105 million years Found: Patagonia Announced: Mar. 2000 |
The largest meat-eater
Found in the desert of Patagonia, this creature is the largest meat-eater ever discovered. It is even longer than the 41-foot-long Gigantosaurus and the 40-foot-long Tyrannosaurus rex. This as-yet-unnamed giant probably looked a lot like T. rex but with a pointy, scissorslike jaw. "I think it would have been terrifying," said one of the excavators. A number of these massive meat-eaters—both adults and youngsters—were found together, possibly drowned. The grouping was a surprise to scientists who had thought that meat-eating dinosaurs traveled alone. They now wonder if the dangerous carnivores in fact hunted as a pack, ganging up on much larger plant-eaters.
| "Dawn Monkey" Weight: 1/2 ounce Length: 3 inches Age: 45 million years Found: China Announced: Mar. 2000 |
The smallest primate
Its foot bones are the size of grains of rice, and it weighs less than a dozen paperclips. Yet the miniature "Dawn Monkey" could represent an evolutionary link between lower primates and higher primates, a group that includes apes and humans. The structure of its tiny ankle bones suggest that it could walk flat footed, using all four legs, like advanced primates. Unlike advanced primates, however, it probably "didn't have a lot of time to be social," guesses one scientist. That's because the little animal had to spend most of its time eating to feed its high-speed metabolism—when it wasn't trying to avoid being eaten by bigger creatures. The discovery of this specimen in Asia suggests that our earliest ancestors did not live in Africa alone, as previously thought.
| Unnamed Herbivore Weight: 20,000 pounds Length: 157 to 167 feet Age: 135 million years Found: Patagonia Announced: Jan. 2000 |
The longest of them all
In a remote desert area of Argentina, a villager found the remains of what is believed to be the world's longest dinosaur. Like Brontosaurus and other plant-eating dinosaurs, this giant creature probably had a small head and a very long neck and tail. But it is at least 25 feet longer than Seismosaurus, which was previously believed to be the largest dinosaur. The lonely region where it was discovered has turned out to be a hotbed of dinosaur fossils. "In Patagonia, walking among the rocks is enough to discover fossils," says a researcher in the area. As they discover ever-larger dinosaurs, it gets harder for scientists to name each massive beast—unfortunately for this unnamed hulker, Gigantosaurus, Supersaurus, and Ultrasaurus are already taken.
| "Tinker" Weight: 1350 pounds Length: 21 feet Age: 66 million years Found: South Dakota Announced: Dec. 1999 |
The most complete young T. Rex
This baby Tyrannosaurus rex, a male, was probably one-quarter the size of its parents, and was still young enough that its spine was not fully developed. Like other youngsters, it had long, gangly legs. But even as a baby it had the bone-crushing jaws of an adult. This suggests that even though a Kid Rex would not have been strong enough to tackle large prey, it ate an adult diet supplied by its parents. This 66-million-year-old baby, nicknamed "Tinker," died with half a duck-billed Platypus in his belly. With a skeleton that could be 90 percent complete, researchers hope to gain new understanding of the T. rex's life cycle. "You're getting a window into the childhood of the world's favorite dinosaur," says one paleontologist. It wasn't an easy childhood—this youngster appears to have been chewed up by a larger dinosaur, perhaps a confused parent.
| Early Prosauropods Weight: unknown Length: 4 to 8 feet Age: 230 million years Found: Madagascar Announced: Oct. 1999 |
The earliest dinosaurs
Jawbones of the two oldest dinosaurs ever found were discovered by a boy on the African island of Madagascar. These prosauropods (early plant-eaters) are estimated to be 230 million years old. Because scientists know so little about that era—when not only dinosaurs but mammals developed—they hope the find will help them to unravel the mysteries of dinosaur evolution. The two plant-eaters are about the size of young cows and probably used their front legs to rummage through plants on the ground, though they could also run on all four legs. Over the next ten or so million years, these little creatures evolved into the huge sauropods we think of when we hear the word dinosaur. "How they got so big so fast is an interesting question," said a scientist working on the find.
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