Trilobites dating back 508 million years have been found preserved in volcanic material, revealing unprecedented detail in 3D. Their fossilization was so rapid that tiny shells were preserved in place, and soft tissue including mouthparts and internal organs can still be seen.
The trilobites were buried in lava flows, the hot, dense material that erupts from volcanoes and sometimes reaches high speeds. 200 meters (656 feet) In the second. Normally, it burns any life in its path, but this can change in a marine environment.
“The sea surface onto which the ash flowed would have been deadly hot and, yes, would have burned animals at its deepest depths,” said one of the study’s authors. Dr. Greg Edgecombe From the Natural History Museum, London, to IFLScience. “The ash likely mixed with seawater during its capture and trapping of trilobites that lived on the sea floor. This mixing in a column of seawater must have cooled the ash sufficiently.”
Collected in the Atlas Mountains of Morocco, these ancient wonders have been dubbed the “Pompeii” trilobites because of their remarkable preservation in the ash. They are incredibly old, but they are not the oldest trilobites ever found.
They are about 508 million years old, younger than the oldest trilobites, which date back to about 521 million years ago. There are also older burrow-shaped trace fossils, called Rusophycus, which are believed to be the work of trilobites and are over 528 million years old.
However, comparative groupers are still remarkable in terms of the degree of preservation they exhibit.
“What makes our specimens unique, especially pristine ones, is the three-dimensional preservation of their appendages,” Edgecombe added. “The appendages have not been flattened, reoriented or broken. They have been preserved in orientations close to life. And because they are preserved in a vacuum in the rock matrix, “We can CT scan it to see it in 3D.”
Microscopic reconstruction of the trilobite Gigoutella mauretanica in ventral view.
Image credit: © Arnaud MAZURIER, IC2MP, University. Poitiers
“Appendages preserved in shale can preserve their shape beautifully but the fossils are so compressed that they are almost two-dimensional and we have to use destructive samples to mechanically coring the upper parts of the appendage in order to see the lower parts. Our specimens are as perfect after study as they were before.”
These never-before-seen details mean we’re now seeing trilobites that are closer to life than we’ve ever seen them before, complete with a slit-like mouth and unique vertical feeding appendages. Isn’t that beautiful?
The study is published in the journal Sciences.
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