Whether they come from dino “dragons,” ancient pandas, or well-endowed crustaceans, fossil finds can offer exciting insights into the creatures that roamed the earth long before modern humans came into the picture. Scientists are interested not only in the skeletal remains that fossils preserve, but also in how the fossils themselves were formed; understanding these processes can help experts get a better idea of extinct animals and the environments they lived in.
Unfortunately, since the fossilization process takes at least ten thousand years, it is not particularly easy to study. So, as Erin Blakemore reports for Popular Science, a team of paleontologists have devised a way to convincingly mimic the process in less than 24 hours.
Typically, scientists learn about fossilization by studying and conducting chemical analysis on naturally occurring fossils. Previous efforts to make fossils in labs have yielded important information about the fossilization process, but Evan Saitta, a Field Museum post-doctoral researcher and lead author of a new paper in Palaeontology, hoped to create fossils that were more realistic than anything that had been produced before.
He tells Erika K. Carlson of Discover that past experimentation involved wrapping specimens in foil or sealed containers before subjecting them to intense heat and pressure. Saitta and his research partner, Tom Kaye of the Foundation for Scientific Advancement, opted instead to pack their specimens into clay in the hopes of simulating the natural fossilization process; fossils form when organisms decay in sediment, and subsequent heat and pressure create an impression of the dead creature in sedimentary rock.
Saitta and Kaye used a hydraulic press to stuff various samples—like lizard limbs and bird feathers—into clay tablets with about the same diameter as a dime. Then they baked the tablets in a laboratory oven at over 410 degrees Fahrenheit and 3500 psi—a pressure 300 times higher than the atmospheric pressure at sea level, according to Carlson.
The researchers let their concoctions bake for about 24 hours. And when they pulled the tablets out of the oven, the “fossils” looked pretty darn good.
“We were absolutely thrilled,” Saitta says in a statement. “We kept arguing over who would get to split open the tablets to reveal the specimens. They looked like real fossils—there were dark films of skin and scales, the bones became browned.”
The fossils (which the statement dubs “Easy-Bake fossils”) also looked convincing under a microscope. Researchers didn’t see any proteins or fatty tissues, which is an encouraging sign, since these materials are not preserved in real fossils. They did, however, see melanosomes, a type of cell structure that contains the biomolecule melanin. Scientists have found melanosomes in naturally occurring fossils; melanosomes have, in fact, helped researchers reconstruct the color and pattern of dinosaur feathers.
Saitta was particularly excited by these findings because he studies “exceptional fossils,” or fossils that preserve skin, feathers or biomolecules. As their name suggests, exceptional fossils are quite rare, so, as Jessica Leigh Hester reports for Atlas Obscura, scientists don’t fully understand how the materials they contain are preserved. Being able to engineer exceptional fossils in a lab could offer new insights into the process.
Of course, the new method isn’t a perfect substitute for the real thing. “There are some paleontologists who say that controlled experimentation is not an appropriate analog, because it doesn’t replicate the natural environment,” paleobiologist Maria McNamara tells Discover’s Carlson. But “Easy-Bake Fossils” could be the next best option. As Saitta notes in the statement, his team’s simulation “saves us from having to run a seventy-million-year-long experiment.”