3D printing is exactly what it sounds like. A machine prints out a design after it has been prepared on a computer. The difference between 3D printing and you printing this blog onto some paper is that this new technology can print 3-dimensional objects. It sounds like science fiction, but it’s here, and it is very useful indeed. Earlier this month, Belgian doctors announced that an 83-year-old woman had become the first person to be given a 3D-printed jawbone transplant. Her own jawbone was badly infected and this seemingly futuristic new technology gave the doctors an extra option. This titanium jawbone and other 3D-printed objects are produced by combining thousands of thin layers on top of each other to finish with a complete 3-dimensional object. Use of this technology has been growing steadily for a decade now, and the cost has reduced considerably too. So far the technology has attracted doctors, engineers, fashion designers, architects… and now palaeontologists.
Dr Kenneth Lacovara, a palaeontologist and Associate Professor of Biology at Drexel University, has begun using 3D-printing and other technologies in order to better understand how the largest dinosaurs moved and behaved. According to Dr Lacovara:
Technology hasn’t changed in 150 years. We are still using shovels and pickaxes and burlap and plaster. It hasn’t changed – until now.
This claim is a little questionable, as palaeontologists have adapted new technologies over the decades. One example would be the use of MRI and CT scans on well-preserved fossils like “Leonardo”, the partially mummified skeleton of a young brachylophosaur discovered in 2000. But Dr Lacovara is absolutely right that most paleontological work in the field still involves shovels and pickaxes. New technology is in use and does help, but hasn’t removed the need for people to get dirty, dusty, and hands-on.
A lot can be learned from looking at fossils, or even trace fossils. Last month I wrote a short news piece about the oldest known dinosaur nesting site discovered. The structure of the nesting site provides evidence that several individuals used the nests, and returned to use the same site. By comparing size data from the preserved embryos and the footprints found around the nests, there is evidence that the young stayed at the nesting site long enough to double in size. Fossils can be more useful than many people think in helping to understand the behaviours of long-extinct organisms. Dinosaur locomotion is no different. Like Sherlock Holmes detecting that a suspect was running due to the impressions of the heel and toes in a footprint, palaeontologists can calculate a dinosaur’s walking and running speeds by comparing data from skeletons and trace fossils (in this case, preserved footprints). But speed is one thing. Understanding the actual movements of a living dinosaur is another thing entirely, especially when you’re interested in a dinosaur that stands 50ft tall.
Dr Lacovara initially contacted mechanical engineer Dr. James Tangorra in order to discuss a new method of replicating fossil bones. Some dinosaur species weighed up to 60 tons. If you wish to manipulate these giant bones, there are two options. Firstly, use the bones themselves. While this would be fairly practical for smaller animals, it isn’t possible to manipulate a giant sauropod skeleton in order to reproduce the limb movement during locomotion. Some of these fossils are also extremely rare, so physically manipulating and stressing the ancient skeletons could result in damage. The alternative is to use casts. Unfortunately, these are still huge, they take up a lot of space, and the process is still fairly expensive. Dr Lacovara was interested in using 3D printing to produce replicas of fossil bones for use in his experiments. Not only did Dr Tangorra suggest that this would be quite possible, he also explained how making these replica skeletons robotic could help mimic the natural locomotion of these large dinosaurs, going as far as creating artificial muscles to move the limbs and test stresses.
Will we ever know exactly how an extinct dinosaur species moved while alive? Possibly not. But these biorobotic skeletons could be the closest we get to figuring it out. Combining the physical biorobots with numerical models, it should be possible to calculate the most efficient modes of locomotion for each species, a common technique used in studies of locomotion. Having physical robotic models to compare to computer simulations could help answer other questions about the largest of the dinosaurs, including how they mated and reproduced. These techniques will always be speculative, but being able to test the predictions of a model by using a lifelike biorobotic dinosaur could be a big step in our understanding of these magnificent animals.
The fossil bones are scanned in 3D so that they can be stored in a digital workspace on a computer. These 3D scans are then prepared so that they can be fed to the 3D printer and a complete replica of the bone can be printed. Bones can be printed in their original size, and sometimes that may prove useful. But the novelty of Lacovara’s work is that he is able to create smaller but perfectly proportioned models of the larger dinosaurs so that they can more easily be manipulated and studied. Personally I look forward to seeing the technology developed to the point where we can test evolutionary hypotheses by changing skeletal structure. The technology also lends itself to other uses such as creating exact-size replicas for museums, or very small-scale replicas for educational purposes.
Lacovara’s team intends to reveal the first working robotic dinosaur limb by the end of the year. We won’t see a complete full-body replica until a couple of years from now.