A one-of-a-kind trilobite fossil hints at what and how these creatures ate

A mysterious, prehistoric marine creature has spilled its guts. For the primary time, scientists have unearthed a fossilized trilobite whose last meals have been preserved inside its digestive system.

Paleontologist Valéria Vaškaninová and colleagues found the partially digested meals after they checked out a high-resolution 3-D scan of Bohemolichas incola, a beforehand identified however comparatively uncommon trilobite species that lived 465 million years in the past. The contents embrace fragments of thin-walled shells, bits of echinoderms (a bunch that features modern-day sea urchins and starfish), and different bottom-dwellers sufficiently small to be swallowed entire, the researchers report on-line September 27 in Nature.

Most of the greater than 20,000 described species of trilobites, a bunch that existed between 520 million and 252 million years in the past, have been outstanding members of marine ecosystems. Some species could have even had twin digestive tracts, although B. incola didn’t (SN: 10/31/14). The brand new discover not solely gives direct proof of what some trilobites could have eaten, nevertheless it additionally hints about their physiology and the way they foraged.

Tightly packed clumps of shelly bits all through the tubelike intestine recommend that the trilobite fed nearly repeatedly earlier than it died, maybe by scavenging the seafloor for damaged stays of shelled creatures and digesting the gentle tissues nonetheless hooked up to them. Trilobites sometimes didn’t have sturdy mouthparts and thus wouldn’t have had a robust chunk, says Vaškaninová, of Charles College in Prague.

And for the reason that calcium-rich shells within the intestine present no indicators of being dissolved, the trilobite in all probability had a intestine setting with an alkaline or impartial pH, Vaškaninová and colleagues recommend. That form of biochemistry would have lowered the quantity of dissolved calcium getting into its bloodstream, which might be metabolically tough to eliminate, the group proposes.

In a small little bit of turnabout-is-fair-play, the scan additionally revealed that B. incola’s carcass had been scavenged by different organisms earlier than fossilizing.