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A Montana rancher found two skeletons in combat — the Dueling Dinosaurs. But who do they belong to, and will the public ever see them? T he early June morning in Montana was already very hot and dry by 7. Phipps, a rancher who calls himself the Dino Cowboy, was wearing his trademark black felt Stetson cattleman hat.
The trio fanned out to hike through the badlands of what they thought was the Judith River Formation; later, they would learn they had actually been in an area called Hell Creek, a division of gray and ochre sandstone, shale and clay deposited about 66m years ago during the Late Cretaceous, when the area was a swampy floodplain. Phipps, like most locals, calls it the Hell Crik. At lunchtime, the group reconvened for roast beef sandwiches. Phipps asked Eatman if he had found anything. They went to the site.
Phipps could tell right away it was from a ceratopsian, a group of herbivorous, beaked dinosaurs. He brushed away some of the sand, and thought there might be more of the dinosaur buried in the hillside. But excavating it would have to wait for another day: he had acres of hay to cut for cattle feed. Eatman went back to Billings, where he had gotten a job at a carpet store after a run of bad luck put an end to his year career as a full-time fossil hunter.
We had no plans to go back, but Chad convinced us to. In the US, fossils found on private land belong to the landowner; prospectors simply need their permission to dig. They built a road to the site.
They began excavating the ceratopsian with penknives and brushes. Business partners were brought in; secret contracts were arranged. Eatman came to help when he could, along with a rotating cast of confidants. After two weeks, the body of the plant-eater had been revealed. Other times it's a mystery. Then maybe it is reason to name a new dinosaur from what you found. Q: How do you know what to pick as a fossil and what to leave on the ground?
A: When we are out prospecting for bones, we first look at modern bones to give us a "search image" with which to look at the ground and to recognize fossil bone when we see it. Still, I pick up a lot of stuff that turns out to be just rock when I look at it under a magnifying glass or hand lens. All that stuff goes back on the ground, and I keep walking until I pick up something that really looks like bone when I look at it more closely.
Shape, color, and texture all help in recognizing fossil bone. Tim Rowe. Q: How do scientists know how dinosaur bones should be put back together? A: Putting bones together isn't too hard if you have a complete skeleton to compare it to. Otherwise it can be tough. Usually the shape of the bone tells you what body part it is.
Mostly scientists don't put dinosaurs back together. It's too expensive, the bones are too valuable for studying, and you rarely get a complete skeleton anyway. Q: How do they know exactly how to put the dinosaurs together?
A: The fact that dinosaur skeletons look so much like the skeletons of birds is one of the things that makes it possible for us to put their skeletons together properly. We also occasionally find complete skeletons, with every bone in place, so there is not much doubt how most of the skeletons go together.
Most skeletons have several hundred individual bones. When the first ones were discovered, scientists were not sure how they went back together until they discovered the resemblance to birds. Q: When there's a pile of bones, how can you tell if they belong to several different dinosaurs? A: Sometimes if the bones are pretty badly broken up it's hard to tell what animal they belonged to.
But interspecific bone beds happen a lot — that means the bones of several species have been washed together. Usually you can tell pretty well what kind of dinosaur made them, at least to the level of what family or group of species. For instance, the little serrated teeth would belong to small meat-eaters and the big flat rib bones would belong to large plant-eaters.
But you need a bone that is diagnostic, which means you can tell by its shape alone what animal uniquely had it, to be able to figure what animal produced the fossil.
Q: How do you know in which period certain dinosaurs lived? A: Usually you can tell the time when the dinosaur lived by the age of the rock it is in. You tell the rock's age by small fossils of plants and little animals that we already know the age of, or by chemical testing if it is volcanic rock. Sometimes we can tell the age of the rock and the fossils in it within , years of the actual time, even if it happened million years ago. Q: How do scientists determine age from the bones?
A: We can't tell the age of dinosaurs by their bones. But you do get some clues both to the age of the individual dinosaur they laid down rings as their teeth and bones grew, a bit like trees, sometimes, but we don't know if that was every year or not and the time when that kind lived — by comparing it with other similar dinosaurs from times already known.
Q: How do scientists determine all of the dates that they give for when the dinosaurs lived, when humans came along, etc.? A: We tell the age of dinosaurs from the rocks they were in or other better known and dated fossils found along with them or near them, particularly mammal teeth and small sea creatures.
We can only date a rock precisely if it was made from a volcano — not by gradual buildup like most dinosaurs are found in. Volcanic rock contains some radioactive minerals in tiny amounts. These minerals break down over time at a very steady rate. By measuring how much of these minerals have broken down we can date such a volcanic rock to within , years of when it was made, even if it was many millions of years ago.
Of course, such volcanic rock isn't always around dinosaur fossils. So often we have to guess from these other clues. Q: What was the first dinosaur discovery? How and where was it found? What was its name? Was it a meat-eater? When did it become extinct? A: The first dinosaur discovered and named was iguanodon in the 's in England, from a tooth brought to a medical doctor named Gideon Mantell.
Iguanodon grew to more than 20 feet long and had a big spike on its thumb. But the first dinosaur scientists goofed and put the spike on its head.
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