from the boreal forest, accidentally discovered by Canadian miners, is one of the most spectacular fossil finds of all time.
In March 2011, a construction worker named Shawn Funk visited an impressive dinosaur collection at the Royal Tyrrell Museum in Alberta. As he walked through halls filled with ancient bones, he had no idea that a week later, he would join them in finding one of the most spectacular dinosaur fossils of all time. It is such a well-preserved animal that its skeleton cannot be seen due to the skin and soft tissues that still cover it.
When we see dinosaurs in museums, it takes imagination to put flesh and skin on the bones. But for the dinosaur that Funk dug up—a 110 million year old creature calledfrom the boreal forest—imagination is not needed.looks like a sculpture. And based on the pigments still hidden inside the skin, scientists think they know what the animal's colors were. "If anyone wants to come face to face with a dinosaur and see what it really looked like, this is the place," says Caleb Brown of the Royal Tyrrell Museum, who studied the animal.
from the boreal forestit was one of the ankylosaurs, a group of squat, short, tank-like dinosaurs. It lacked the tail clubs that some of its kin wore, but its back was covered in heavy armored scales, and a pair of 20-inch-long spikes protruded from its shoulders. It weighed 1.5 tons and measured 20 feet from foot to tail. And he probably couldn't swim very well.
Somehow this particular individual ended up at sea. Perhaps he was overlooked on the coast. Perhaps he drowned in a flood and was washed out to sea. Either way, gases began to build up in his body, making him float on his back. When these gases were released, the dead dinosaur sank and hit the ocean floor hard enough to leave a small crater. Before the sharks had a chance to bite him, or the worms had a chance to burrow into his bones, he was quickly smothered in fine sediment and cut off from the outside world. There it remained for millions of years, until March 11, 2011, when a bulldozer bit it.
By this time, the bottom of the ocean that had swallowed the dinosaur had become the Millennium Mine, a huge tar sand quarry in northern Alberta. Funk, a heavy equipment operator, was digging in the mine when he noticed a change in the texture and color of the underlying rock. Alberta is rich in fossils, and construction crews know that any dig can yield fresh bones. Funk called his supervisor and they alerted the Royal Tyrrell Museum.
Two days later, Donald Henderson and Darren Tanke flew over, expecting to find the bones of a marine reptile, perhaps a long-necked plesiosaur or a dolphin-like ichthyosaur, whose fossils are commonly found in Alberta. But when they arrived, they realized that the miners had discovered something special: a dinosaur. The bulldozers had already destroyed the animal's tail and rump, which were lost forever. But most of the creature was still there, and even then, it was clear that it had strange features, like fossilized skin. “I don't think anyone realized how magnificent the specimen would be,” says Brown.
After three days of intense security training, the team began releasing the dinosaur, a process that took two weeks of laborious 12-hour shifts. “All mine personnel from all levels and departments were tripping over each other and offering to help,”Henderson later wrote inThe Guardian. They finally isolated a single 15,000-pound block containing the animal, lined with burlap and plaster. But when they lifted the block, the jacket ripped and the block collapsed, a horrible moment,immortalized in video.
Luckily, it all broke cleanly and in big chunks, all of which were sent to the museum. One might think that a large team would process the fossil, but the museum's team of a dozen technicians is already at its limit. Each year, Alberta discovers more dinosaur specimens than Royal Tyrrell can collect, so many are left in the ground. Of those who recover, many remain in warehouses. Ankylosaurus clearly deserved special attention, but due to its delicate state, it was assigned to only one pair of steady hands.
Those hands belonged to technician Mark Mitchell, who compares the process of separating dinosaurs from rock to chipping away pieces of concrete from a surface as smooth as compressed talcum powder. It took 7,000 hours over 5.5 years, during which he did little else. That's why the dinosaur is named after him—Markmitchelli de Borealope. (The first half comes from the Latin for "shield of the north".)
The finished specimen, now on public display, is impressive and reassuring. It's difficult to reconstruct what animals look like based on bones alone: an elephant's skeleton has no obvious traces of its trunk, and a bird's skeleton offers little clue as to its thick plumage. Thus, paleontologists have debated whethergiant dinosaurs had trunks, or if all speciesthey were covered in some kind of feathers. But stopfrom the boreal forest, "what we thought this animal was based on the skeleton is what it actually looks like," says Brown. "And it probably had scaly skin."
It's a good time to be interested in ankylosaurs. Another new and well-preserved species was revealed last month:the blood-curdling roar,monster nameGhostbusterand the Latin for "destroyer of pimples". "It's so wonderful to have two amazing new ankylosaurus skeletons with the armor in place," says Victoria Arbor of the Royal Ontario Museum in Toronto, who named and describedZuul. "It really helps us visualize what these strange dinosaurs would have looked like while they were alive."
the way offrom the boreal forest'''s face and body are easy to see, but its remains have long since lost their natural color and are now black with ocher flecks. Still, they contain chemical clues to their original tones. To interpret these clues, the Royal Tyrrell team turned to Jakob Vinther of the University of Bristol.
In 2007, Vinther began studying tiny pigmented structures called melanosomes, found in the feathers of fossilized dinosaurs. These come in two types: spherical ones that are reddish-brown in color and sausage-shaped ones that are black or gray. By observing the propagation of melanosomes through the body of a dinosaur, Vinther was able to reconstruct the blades of these extinct animals. He discovered that the little hunterAnchorit had a black and gray body with a red crest, while the four-wingedMicroraptorshared the glossy black plumage of a modern starling, and that theparrot faceparrothe had a dark back and a light belly.
Vinther could not find any melanosomes infrom the boreal forestPero's skin found traces of chemicals called benzothiazoles, which are part of reddish-brown pigments. Based on the distribution of these chemicals, the team believes that their ankylosaurus had the same pattern ofPsittacosaurus—rust-colored head and back and pale belly.
This pattern, dark on top and light on the bottom, is called counter shading and is one of the most common forms of camouflage in nature. If an animal were uniformly colored, its own shadow would make the bottom half darker than the top half, making it easier to spot. Counter shading, by lightening the bottom and darkening the top, cancels out the shadow effect and makes the animals appear flat and unobtrusive.
On land, counter-shading is a common trick among animals that need to hide from predators such as deer, antelope and wild horses. But once the tusks grow large enough, their bulk provides them with sufficient defense, which is why rhinos and elephants are uniformly gray.from the boreal forestbreak that trend. It is the size of a rhinoceros and much larger than any dark land animal today. “The fact that this huge armored dinosaur with these massive spines still had back-hatching tells us that it was a common meal for predators at the time,” says Brown. These predators could have includedacrocantosaurio, whiletyrannosaurusbut of lighter construction.
It may seem obvious that herbivores likefrom the boreal forestThey were hunted by large predators. But "some people believed an animal like this was predator-proof," says Brown. "To get into the animal, you would have to turn it over on its stomach, and it's huge." Clearly, though, enough predators were doing this to drive the evolution of a camouflage color scheme.
But Alison Moyer of Drexel University, who studies ancient molecules, is unconvinced for several reasons. For example, he points out that benzothiazoles occur naturally in the sea, and it is not clear whether the traces found in the seafrom the boreal forestspecimen came from the dinosaur itself. It is also unclear how the animal's pigments would have changed as it floated face-up on the ocean's surface. “We know a lot about what happens to human skin when it swells and fluctuates, and there are drastic changes between the side exposed to water and the side exposed to air,” says Moyer. For a dinosaur, "we don't know anything about how its soft tissues break down."
“There is still a lot of healthy scientific skepticism around the interpretation of ancient biomolecules as pigments,” says Arbor. “It's really difficult to collect enough data to allow us to reconstruct color patterns in extinct dinosaurs. But for now, I'm excited about the exceptional preservation of this specimen and what we can get out of it in the long term. It's so beautiful!
Team members are now trying to analyze the ankylosaurus' intestinal contents, to see if they can identify its last meal. They are also trying to analyze your bones. This is usually the easy part when it comes to studying dinosaurs, but withof the boreal forest,the skeleton is obscured by the skin. “We've tried to use CT scanners, but so far it hasn't worked. The rock is very dense, but hopefully future technology will allow us to look inside. Ironically, it is very well preserved!”