Time and again I have stressed that every fossil bone tells a story, and, in a different way, so do coprolites. Fossilized feces are small snapshots of the lives of prehistoric organisms, often preserving bits of whatever they had been eating, and while coprolites may not get top billing in museum halls, they are among the most pungent reminders that weird and wonderful organisms really did live during the remote past. As reported by paleontologists James Farlow, Karen Chin, Anne Argast, and Sean Poppy in the latest issue of the Journal of Vertebrate Paleontology, two such vestiges of ancient digestive systems have recently been found in Indiana, but what left them is something of a mystery.
Called the Pipe Creek Sinkhole, the site where the coprolites were found dates back to around five million years ago. During that time Indiana was home to a motley assemblage of mammals. As stated by the authors, remains of “insectivores, rodents, hares, peccaries, deerlike ungulates, camelids, rhinoceroses, felids, canids, skunks, and bears” have been found there, but what sort of animal left the scat behind? To find out, the scientists attempted to parse the details of the fossils through thin sections and CT scans.
What the paleontologists found was that the coprolites – measuring 50 mm long × 26 mm maximum diameter and 30 long × 26 mm maximum diameter, respectively – were similar in chemical composition to scat produced by meat-eating animals. This was confirmed by remains discovered within one of the specimens. While one coprolite lacked internal detail, the other (INSM 71.3.144.3000) preserved hairs and two teeth from a small carnivorous mammal, perhaps a skunk, indicating that whatever creature produced the scat was itself a carnivore.
The determination that the coprolites were made by a meat-eating animal narrowed down the list of suspects, but the actual identity of the scat-maker proved difficult to ascertain. The enamel of the teeth found in the coprolite was eroded away, something which has been seen in coprolites attributed to crocodiles. The trouble was that no crocodile remains had been found at Pipe Creek Sinkhole. Additionally, while the scats were similar to those made by snapping turtles observed by the scientists in aquaria, the researchers stated that they are doubtful that the scats were left by a turtle due to the relatively large size of the scats and the lack of enamel-eroded teeth in the modern samples for close comparison.
The only other candidates were the large, meat-eating or omnivorous mammals of the site. Of those animals, it seemed most likely that the scats were left by a canid, especially since experimental tests of how dogs consume and digest white-tailed deer jaws have previously confirmed that whole teeth can sometimes make their way into the stomach where their enamel is dissolved before being deposited as scat. While the authors could not rule-out a large turtle as the scat-maker, on the basis of these observations they assigned the coprolites to a wolf-sized canid. Regardless of the identity of what animal left the scat, though, it is wonderful that such signs of ancient life have been preserved, and through using techniques like those employed in this study paleontologists can begin to better resolve the paleobiology of long-dead organisms.
James O. Farlow; Karen Chin; Anne Argast;Sean Poppy (2010). Coprolites from the Pipe Creek Sinkhole (Late Neogene, Grant County, Indiana, U.S.A.) Journal of Verterbrate Paleontology, 30 (3), 959-969 : 10.1080/02724631003762906
Go Further
Animals
- These 'trash fish' are among Earth's most primitive animalsThese 'trash fish' are among Earth's most primitive animals
- These photos are works of art—and the artists are bugsThese photos are works of art—and the artists are bugs
- The epic migration of a 6-foot long, 200-pound catfishThe epic migration of a 6-foot long, 200-pound catfish
- Frans de Waal, biologist who studied animal emotion, dies at 75Frans de Waal, biologist who studied animal emotion, dies at 75
Environment
- Are synthetic diamonds really better for the planet? The answer isn't clear-cut.Are synthetic diamonds really better for the planet? The answer isn't clear-cut.
- This year's cherry blossom peak bloom was a warning signThis year's cherry blossom peak bloom was a warning sign
- The U.S. just announced an asbestos ban. What took so long?The U.S. just announced an asbestos ban. What took so long?
- The most dangerous job? Inside the world of underwater weldersThe most dangerous job? Inside the world of underwater welders
- The harrowing flight that wild whooping cranes make to surviveThe harrowing flight that wild whooping cranes make to survive
History & Culture
- Meet the powerful yokai that inspired the demon king in ‘Demon Slayer’Meet the powerful yokai that inspired the demon king in ‘Demon Slayer’
- A surprising must-wear for European monarchs? Weasels.A surprising must-wear for European monarchs? Weasels.
- Meet the woman who made Polaroid into a cultural iconMeet the woman who made Polaroid into a cultural icon
- Inside the observatory that birthed modern astrophysicsInside the observatory that birthed modern astrophysics
Science
- LED light treatments for skin are trendy—but do they actually work?LED light treatments for skin are trendy—but do they actually work?
- NASA smashed an asteroid. The debris could hit Mars.NASA smashed an asteroid. The debris could hit Mars.
- Humans really can have superpowers—scientists are studying themHumans really can have superpowers—scientists are studying them
- Why engineers are concerned about aging infrastructureWhy engineers are concerned about aging infrastructure
Travel
- Play and stay in the mountains of eastern Nevada
- Paid Content
Play and stay in the mountains of eastern Nevada - This couple quit the city to grow wasabi in Japan's mountainsThis couple quit the city to grow wasabi in Japan's mountains