With a crest on its head loosely resembling hair styled into a pompadour, Cryolophosaurus lived, once upon a time, in the middle of present-day Antarctica. Giganotosaurus was a carnivore, similar in size and fearsome appearance to Tyrannosaurus rex. And Futalognkosaurus, at more than 30 metres long, may well have been the largest terrestrial animal of all time.
If you’ve never heard any of these names before, you’re likely not alone. Cryolophosaurus and company were among the great many dinosaurs that lived on a Mesozoic-Era supercontinent called Gondwana, which sat below the equator.
“[North Americans] think of T. rex, Triceratops, duck-billed dinosaurs, Stegosaurus,” explains paleontologist David Evans, head of dinosaur research at the ROM. “These are all representatives of classic dinosaur groups that occur essentially only in the Northern Hemisphere. And there’s a whole series of other big dinosaur groups, that are only found in the Southern Hemisphere, that we just don’t get exposed to very often.”
The task of making and assembling the casts is giant, also. Enter Peter May.
A sculptor by training, May began working with fossils at the ROM in the 1970s, and started up his own dinosaur-building company in 1986. Originally located in Toronto, Research Casting International is now stationed in a 4,600-square-metre facility in Trenton that is like a cross between an airplane hangar and a machine shop.
It is here that May and his team make moulds and casts of fossils in the traditional style or, increasingly often, make 3D scans and prints instead. In order to recreate Futalognkosaurus, for instance, May travelled to Argentina to scan the fossilized elements of the dinosaur. From those scans, he will develop a digital model, which will eventually be carved out of foam on a massive milling machine.
Evans—who makes regular trips to the Trenton shop to ensure the various skeletons’ faithful reconstruction and anatomic correctness—adds that the use of digital technology not only facilitates building dinosaurs, but understanding them as well.
Dinosaur bones tend to be big, heavy, and unwieldy. “If you’ve got a six-foot thigh bone, how are you going to [physically] manipulate that relative to the hip socket?” Evans asks rhetorically. But by scanning the fossils, he says, “you actually get to put the bones [in place, digitally] and see how they function together in 3D space.”
Which is fortunate because, as paleontologists take their search for fossils to previously neglected areas of the globe, more and different thighbones are going to start turning up. Because of a combination of factors like the high cost of the work, political instability in parts of South America and Africa, a surfeit of paleontologists in North America, and the logistical difficulties of hunting for bones in distant countries, much of the Southern Hemisphere’s fossil record remains undiscovered.
“It’s really only been in the last 20 years […] where we’ve started to see really intensive exploration of some of the richest fossil fields in the Southern Hemisphere,” Evans says. “We’re going to places and digging things up for the first time.”
Forecasts of what remains to be discovered can be no more than guesswork. “We’ve named more dinosaurs in the last 20 years,” Evans says, “than we had named in the hundred years before that.”