CHARLOTTE, N.C. - Prehistoric bones discovered in North Carolina seven years ago are painting the most complete picture science has ever had of animals that roamed eastern North America about 215 million years ago, before dinosaurs took over Earth.
Initially the bones were thought to be the fossilized skeleton of one creature - a meat-eating reptile called a rauisuchian that weighed about 1,500 pounds and reached to 6 feet, standing on its hind legs.
But as researchers - from Toronto to New York to Chapel Hill, N.C. - began extracting the rock-encrusted bones, they realized they had much more.
This one find includes large parts of the skeletons of four animals and a few pieces of two others, all from the Triassic period before the Atlantic Ocean was formed.
Two of the fossils are of new species. Three are most likely the best of their kind ever found.
Just as important as what was unearthed is where it was found.
For years scientists believed that gashes in the earth such as the one that held these bones were nearly barren of fossils. Now, thanks to this discovery, they realize they could be flush with bones that are hundreds of millions of years older than man.
"We went, with this one discovery, to knowing very little about life at the beginning of the age of the dinosaur to knowing very much," says Hans Sues, a Harvard-trained paleontologist, professor at the University of Toronto and vice president of the Royal Ontario Museum.
"This is one of the most important finds ever made in terms of fossil discovery."
Two UNC-Chapel Hill students happened upon these bones in 1994. Immediately, they took them to paleontology professor Joe Carter, who started calling his colleagues for help.
It took a year and a half for researchers to realize they had more than one creature; an additional 4 1/2 years to clean most of the bones.
Before long though, Carter, Sues and Paul Olsen, a Columbia University professor who specializes in Triassic life, were piecing together an astonishing prehistoric puzzle.
First was the skeleton of the rauisuchian (raw-ih-SOO-ke-un) - a large reptile, 11 feet long, that lived before birds.
It is the first definite rauisuchian found in eastern North America.
"And this skeleton is, in many ways, one of the best rauisuchian skeletons in existence," Olsen says.
Not only did Carter and his students uncover 75 percent of its bones, they were preserved, for the most part, in perfect order, so scientists didn't have to guess which bone was connected to which.
Even more important are its hands. They show two interlocking fingers, something never before seen, making this a new species and genus.
Carter and students spent until late last year cleaning those. They wait now, locked on the UNC campus, to be assembled, a process that will take two to three years.
The second fossil found at the site lay underneath the first.
A cousin to the crocodile, it ran fast on long, thin legs - a combination crocodile and greyhound, Sues says.
Because this creature, in the sphenosuchian family, is a new species, too, it, like the rauisuchian, will get a new name.
"I've worked for over 20 years on Triassic reptiles from the Eastern Seaboard, and I never thought we would find anything this complete back East," Sues says.
Including its tail, the sphenosuchian was 4 or 5 feet long with a small, wedge-shaped head.
A visible bite mark in its skull matches, exactly, one of rauisuchian's teeth.
Next come the fossils of animals the rauisuchian had already eaten - gut contents, the scientists call them.
Among those is the skull, an arm bone and a shoulder bone of a baby animal so small its skull is only 2 or 3 inches long. It is called a cynodont. While not this particular type, it is the animal that ultimately gave rise to mammals.
Until this, the cynodont was commonly found in the Southern Hemisphere. A discovery in the Northern Hemisphere is further confirmation that Earth was one continent that split apart - the cynodont could never have crossed an ocean.
The fourth fossil, also found in the rauisuchian's belly, is an armor-plated creature called an aetosaur - an early armadillo-like reptile. It could be the most complete one ever found in the Eastern United States, Sues says.
Such armor plates had been found before, but not much else.
Sues is studying these fossils in Toronto and will return them to Chapel Hill once his research is finished.
Tiny pieces of two other creatures were found in the rauisuchian's stomach, but little is known about those. Sues continues to study a remaining tangle of bone that could yield something more.
"It's sort of a smorgasbord of Triassic life," Sues says of the entire find. "The Triassic all-you-can-eat buffet."
That has led scientists to joke that it was indigestion that killed the rauisuchian. More seriously, they speculate it was attacked by a pack of crocodile-like creatures like the one that lay beneath it.
The fossils belong to Triangle Brick Co., the privately held company that was excavating the site where they were found.
The company hopes to keep secret the exact location, somewhere south of Durham, N.C., to protect it. It plans to donate the fossils, most likely to a museum, a spokesman says.
What can't go to a museum, though, is the last find, which could be one of the most significant - the ground that cradled these fossils for hundreds of millions of years.
"For most of my working life, I ignored this kind of rock because everybody knew it had nothing in it," Olsen says. "And it turns out to be absolutely wrong."
The basin in which it was found is one of 15 that run from Nova Scotia to South Carolina.
So this is a revelation that keeps on giving. Already, it has led to other significant finds in the other basins, Olsen says.
"I can't talk about the specifics of them, but they're really spectacular."
Taken together, Olsen says, all of the discoveries from this one spot in North Carolina teach a much bigger lesson to all of us:
"You don't have to travel to exotic places to make important discoveries.
"It's not where you are, it's what you're doing. If you're persistent you'll find things."