An unexpected discovery hidden in the feces of fossilized dinosaurs shocked experts

Labatilla

July 02, 2021, 4:05 pm

Imagine a group of beetles happily gathering on a moss-covered rock, when they were suddenly sucked in by the beak of a long-necked, slender-necked dinosaur ancestor. Rest in peace… The good news was that through a complex combination of luck and microbial activity, their little corpses were frozen in time. And after more than 200 million years, a group of scientists found it while searching in fossilized feces.

Bor Eli Chichit / The New York Times

These coprolites, as they are called, can provide insights with an extraordinary level of detail about long-vanished ecosystems, according to new research published in Current Biology. A team of researchers has found nearly intact beetles, already extinct, unknown to science, hanging inside a piece of Triassic faeces. Scientists suspect the fecal material belongs to Silesaurus opolensis, a close relative of dinosaurs that lived about 230 million years ago, though it’s difficult to identify once separated from its point of origin.

“We decided to look at coprolites to try to understand who was eating who in this ecosystem,” explained the paper’s lead author, Martin Kvarnström, a paleontologist at Uppsala University in Sweden. “And in one of the fragments of the coprolite, all these beetles appeared.”

Coprolites were collected near the village of Krasiejów in southern Poland, in a quarry where the remains of S. opolensis and other higher Triassic vertebrates were dug. At the excavation site, recalls Grzegorz Niedzwiedzki, a co-author and paleontologist at Uppsala University, few other scholars were interested in cobulite; He said many of them are still lying there. However, the inconspicuous structures can act as “miniature coffins” that preserve fragile items such as hair, feathers, and in this case, 3-D insects, for hundreds of millions of years.

“Over time, we have discovered that coprolites can provide fossil evidence of very ancient organisms that would not normally be preserved otherwise,” explained Karen Chin, a paleontologist at the University of Colorado at Boulder, who was not involved in the study.

However, examining the interior of the coprolites can be difficult, Qvarnstrom admitted. So the researchers took these samples to the European Synchrotron Radiation Laboratory in France to scan their contents and make a 3D rendering.

The most difficult task, Qvarnstrom said, is to combine the images that are produced to distinguish what is what. In addition to the beetles, the coprolite contained “little bits of who-knows-what, it’s just small, digested bits of something.”

Other researchers were also surprised by the healthy beetles present in the sample.

“I was shocked at how well these things were preserved,” said Sam Heads, curator of paleontology at the Illinois Natural History Survey, who was not involved in the study.

At first, Qvarnstrom thought the bugs must have climbed up the stool after defecation. But the researchers noted many different stages of “mastication”, so to speak, from almost completely preserved and boiled carcasses to severed heads, wings and other parts, many of which belong to the same class of beetle, which are 1.5 mm long and have the shape of a boat .

The researchers determined that the new species and genus, Triamyxa coprolithica, belonged to an extinct and previously unknown family in a strain of small beetles known as myxophagi, which today tend to live in algae mats. According to the authors, this is the first insect species to be described in the fossilized feces of a vertebrate.

In terms of explaining how some beetles manage to pass through an animal’s intestines and come out almost unscathed, Qvarnstrom thinks there are some possibilities. The beetles were small and may have been sucked up en masse by mistake while collecting on a piece of algae that had been eaten by Cilisaurus opulensis; Its exoskeleton also appears to have protected it a little, as with modern beetles. Qvarnstrom speculated that those who were not chewed died soon. “They didn’t have to choke on their stool.”

Beetles are perhaps the most diverse group of organisms on the planet, and learning more about their early evolution can help researchers understand why they existed, said Martin Vikaczek, co-author and entomologist at National Sun Yat-sen University in Taiwan.

The Triassic period, in which this coprolite was produced, is similar to a black hole in terms of the information we have from the fossil record of insects, Hades said. “The Triassic beetle is a really important find.”

Qvarnstrom said learning more about the diet of dinosaur relatives would also help researchers better understand how these creatures emerged in an ecologically dominant niche.

“If we want to know more about the past, I think it is very important to get all the pieces of the puzzle,” he concluded.