Picture a paleontologist and you probably imagine someone in a rocky desert digging up dinosaur bones, or hunched over a slab of rock in a lab, slowly chipping away ancient sediment layers to reveal the fossilized remains of a bygone epoch.
But according to a new paper penned by University of Bristol paleontologists, that image of solitary, dusty dinosaur scientists is sorely out of date.
John Cunningham, the paper’s lead author, says the modern study of extinct animals is being driven by cutting-edge imaging technology, 3D modeling and virtual reconstruction and dissection—advancing our knowledge of the ancient animals but also of other species old and new.
New imaging techniques are even allowing fossils to be virtually removed from surrounding rock, saving months or years of meticulous work; the resulting virtual bones can be easily shared and studied, or even printed.
As it has with so many other industries, 3D printing and modeling is helping paleontologists get a clearer look at fossils than ever before. With 3D models, scientists can manipulate specific parts of the specimen for further study, replace missing sections with data from another part of that bone or digitally reconstruct skulls or other complex structures that have been flattened or otherwise distorted during the fossilization process. Soft tissues, such as the inside of the brain case, or muscles that attach at discernible points on the bones, can also be virtually reconstructed.
Once these precise models are created, the fossils can be tested in new ways, such as subjecting them to biomechanical analysis, the same way structural engineers test bridges and buildings before they’re built. This can tell scientists how a given animal could have walked, what it ate, how fast it could move, and what kinds of movements it couldn't make because of limitations of its bone and muscle.
Advances in X-ray imaging and electron microscopy, which uses beams of electrons to create an image of a specimen, are also allowing scientists to peer with a surprising level of detail not only into rocks containing fossils that have yet to be fully physically exposed, but inside the bodies of the fossilized animals themselves.
A team in Germany, for instance, recently announced they’d discovered the earliest known bird to pollinate plants because they were able to see and distinguish multiple species of pollen grains in the stomach of the 47 million-year-old fossil.
Amazingly, though, Cunningham says there are even more precise methods for imaging. Synchrotron tomography, which uses a particle accelerator to produce very bright X-rays, results in precise, clean images, Cunningham says, making visible structures smaller than a thousandth of a millimeter, or one one-hundredth the thickness of a starnd of human hair.
“Using synchrotron tomography we have been able to visualize preserved subcellular structures including possible nuclei,” Cunningham says. “It is even possible to dissect out such structures entirely virtually.”
While time-consuming to create, the quickly-growing stockpile of digital fossil data is offering new opportunities for collaboration, along with the ability to compare dozens of specimens from institutions across the world.
For instance, Norell says, one of his students just completed a dissertation involving inner-ear reconstruction of living and fossilized snakes. She included about a hundred specimens, but "actually scanned only about half of that,” Norell says. “The others were things that other people had already published [so] those raw scans had already been uploaded.”
But despite the progress, Cunningham and his team say old laws that tie fossil copyrights to museums, and a lack of a large-scale electronic infrastructure to store and share data, is holding the field back from more rapid advances.
Some researchers also aren’t as keen to share their data as they should be, even after publishing, if there’s potential for further studies buried in the data, Cunningham says. Many museums copyright their fossils, which prevents legal sharing, and others are also exploiting cutting-edge paleontology tech for profit, he says.
"Some are wary of the allowing widespread access to digital data as it would mean anybody with access to a 3D printer could start printing models," Cunningham says— which may be good for hobbyists and high-school science teachers but could hurt the bottom line of of the institution that owns the data.
Beyond collecting the data itself, a big challenge for institutions is the ability to store, maintain and make available the large amounts of data now being generated by paleontologists, Cunningham says.
In the U.S., however, Norell says there are several data repositories— like Digimorph at the University of Austin, MorphoBank at Stony Brook, or Morphbank at Florida State University—available to researchers. He also doesn’t think the technical and financial hurdles of storing and sharing the data are all that difficult to overcome.
“I work with a bunch of astronomers here at the museum, and the kinds of data that streams in from their instruments is like three orders of magnitude bigger than the kinds of data we get from out tomography studies,” Norell says. “So it’s an issue, but it’s not a problem.”
Learning From The Living
The two agree, though, that one of the major issues now facing the field of paleontology is how surprisingly little we know about modern, living animals.
As Cunningham and the other authors point out in their paper, “…the foremost limitations on reading the fossil record now lie principally, and somewhat ironically, with the poor state of knowledge of the anatomy of the living biota.”
Norell has run into this issue as well. His lab has been virtually reconstructing the brains of dinosaurs that are closely related to birds. But when they started searching for comparative data in modern animals, they couldn’t find a single brain activation map for a living bird. So his collaborators at the Brookhaven National Laboratory had to build a tiny PET scan helmet for birds, and collect the modern data they need for their ancient comparisons themselves.
“Previously, most paleontologists were primarily trained as geologists,” Norell says. “Now … most of us consider ourselves to be biologists who work on fossils sometimes.”