PALAEONTOLOGISTS USE FOSSILS TO TELL US ABOUT THE HISTORY OF LIFE ON EARTH!
Have a question of your own? Ask our paleontologist, Dr. Emily Bamforth (curator@dinomuseum.ca)!
In total, some 11 different kinds of dinosaur have been found in the Grande Prairie region. Small carnivorous dinosaurs such as Saurornitholestes, Richardoestesia, Paronychodon and Troodon have all been identified by isolated teeth. The hadrosaur Edmontosaurus and at least two species of horned ceratopsian (including Pachyrhinosaurus) are also known for certain. Some dinosaurs, like tyrannosaurs, we are uncertain about which exact species lived here and it is likely that there were more than one species of these giant predators. There is also tantalizing evidence of armoured ankylosaurs, dome-headed pachycephalosaurs, and ostrich-like ornithomimids. There are of course additional species of lizards, fish, crocodiles and other animals that have not been listed here.
For those who have seen the Jurassic Park movies, you might have noticed the dinosaurs becoming more furry and feathery in the later films. This reflects our ever-changing ideas about dinosaurs. There is now compelling evidence showing that primitive birds evolved during the Jurassic some 180 million years ago from small carnivorous dinosaurs. Many dinosaur fossils even preserve feathers that are virtually indistinguishable from modern birds. If you ever want to see a live dinosaur, all you need to do is step outside!
Although the discovery of dinosaurs is generally attributed to the English medical doctor, Gideon Mantell in 1822, native peoples across the globe have been aware of these beasts for many hundreds, probably thousands of years. The griffin and dragons of Chinese mythology can be traced back to dinosaur bones that scatter the badlands of Inner Mongolia. Three-toed dinosaur footprints in Qijiang County, China were interpreted as lotus blossoms by the local people 750 years ago. The Navajo, Apache, and other Native American cultures also recognized dinosaur footprints, interpreting them as footprints of a giant bird. Native Americans in southern Alberta regarded giant bones in the area of Dinosaur Provincial Park as the grandfather of the buffalo.
Quite simply, no. Archaeologists study human history whereas palaeontologists study all other fossil life forms. An archaeologist focuses on a single species, Homo sapiens (in other words, human beings). A palaeontologist on the other hand could study everything from microscopic marine life and fossil fish to insects and wooly mammoths! A person who studies fossil plants, however, is known as a palaeobotanist.
Contrary to what many people think (and what ‘Jurassic Park’ might have told you), there are no fancy tricks or technology used to find bones under the ground. A palaeontologist must first understand the rocks to identify the area that is most likely to produce the fossils she wants. For example, only sedimentary rocks contain fossils, unlike things like volcanic rocks. If you are interested in fossil sea life, then you must locate marine rocks. If you are interested in dinosaurs, you must look for rocks that formed on or near the land. They must also be the right age. Then it is a matter of walking and looking for pieces of bone on the surface, which may eventually require further investigation and excavation.
Tyrannosaurus still holds the record for the longest (and perhaps more importantly, bulkiest) carnivorous dinosaur. At 12-13 m long it would have been unrivalled in its environment only by others of its own species. Although they never would have crossed paths, several species do have skulls that were even bigger than T. rex.Spinosaurus, Carcharodontosaurus (both from Africa), Giganotosaurus and Mapusaurus (from Argentina) all have skulls close to 2 metres long! The average person could lie quite comfortably inside the mouth of any of these predators (assuming it was dead of course), but the rest of the body was more delicately built and a bit shorter than the largest Tyrannosaurus.
Palaeontologists rely on well-known and complete skeletons to get a picture of what an animal looked like. However, complete skeletons are rare. When one is left with only a single bone or tooth, they must compare it to other better-known specimens. Only when you find something that closely matches your bone can you can make an educated guess as to what the rest of the animal looked like. Nevertheless, such reconstructions are always tentative and may require changes and remodeling when new material is found. But that’s palaeontology for you!
Until very recently, this question would have been answered with a shrug; however, thanks to some spectacular fossils from China, we are starting to get an idea of what at least some dinosaurs would have looked like. Many specimens of feathered or ‘hairy’ dinosaurs are now known from a site in Liaoning, China. Although colour does not fossilize, scientists have identified colour-specific proteins that are responsible for black and rusty hues. The hair on the tail at least one little dinosaur called Sinosauropteryx, was stripy with reddish hues.
It is difficult to understand how exactly an animal moved, especially one that has been extinct for 65 million years. Perhaps the best evidence comes from dinosaur trackways. By observing modern animals, R. McNeill Alexander recognised a relationship between the size of an animal, its footprints, and how widely-spaced apart they are. Using this equation, palaeontologists have estimated speeds from a variety of trackways. The fastest came from an ornithomimid (or ‘ostrich mimic’ dinosaur) clocked at about 9 metres per second – about the same as an Olympic sprinter.
For a new species to be named, a palaeontologist (or team of palaeontologists) must first determine what exactly makes this particular animal different from all other species. Only then will they come up with a name. Names usually derive from a where the animal was found, some feature of its appearance, or perhaps it honours the person who found the bones (the person who found it isn’t necessarily the person who will study and name it). For example, Hesperonychus elizabethae means ‘West claw’—referencing western Canada where it was found—and ‘elizabethae’ refers to Dr. Elizabeth Nicholls who found the first specimen.
In Alberta, there are strict rules that apply to dinosaur bones and other fossils. Only a professional palaeontologist with a valid collecting permit can excavate dinosaur fossils; however, he or she can enlist other people or volunteers on that permit even if they are not professionals. It is illegal for anyone, even professionals, to excavate without a permit and fines of up to $50,000 or 1 year in prison can occur! Don’t panic though; these rules don’t apply to fossils you might find lying on the ground as you’re hiking. Picking up fossils on the surface is not considered ‘excavating’ and therefore not illegal; however, the government can request they be donated to a museum if they are deemed to be particularly important.
Two simple reasons: it was a good place for dinosaurs to live and a perfect place to die! During the Cretaceous, Alberta was much warmer than it is currently, which supported rich and diverse plant life. Large herbivorous dinosaurs thrived on the lush vegetation, which in turn supported many types of carnivorous dinosaurs. In death, the many rivers that stretched across the landscape provided perfect burial grounds: shifting sands and frequent floods rapidly buried bones that lay on the floodplains eventually fossilizing them. Lastly, erosion (mostly from the ice age) removed the layers of rock that had built up after the dinosaurs went extinct and exhumed some of these buried remains for us to find on the surface.