91Թ Research Reveals the Surprising Eating Habits of Ancient “Hell Pigs”
By Fabiana Fragoso, PhD – ESI Scientific Communications Volunteer
For more than a century, paleontologists have debated what the prehistoric mammals known as “hell pigs” were actually eating. Despite their nickname, these animals were actually more closely related to whales and hippos than to modern pigs. With unusually long snouts, massive jaws, and heavy skulls, Archaeotherium certainly looked intimidating. Some scientists have imagined them as active predators hunting across ancient North American landscapes. Others have suggested they were omnivores, scavengers, or even rooters feeding heavily on vegetation.
Now, new research led by graduate student Brynn Wooten of the suggests the answer may be far more complicated — and far more interesting — than anyone expected. The study, published recently in Palaeogeography, Palaeoclimatology, Palaeoecology, used microscopic wear patterns preserved on fossil teeth to reconstruct what these animals were eating nearly 30 million years ago.
Dental Microwear Texture Analysis (DMTA) is a technique that examines microscopic scratches and pits left on teeth by foods consumed during life. “The best analogy I can think of,” Wooten said, “is when you are walking on the sidewalk, the concrete looks flat. However, if you got on your hands and knees and looked really closely, you would see texture, cracks, peaks, and valleys. DMTA is very similar.”
Under a confocal microscope, the tooth surface reveals an intricate landscape of textures invisible to the naked eye.
Although DMTA data cannot identify every food these animals consumed, it can tell scientists whether those foods were relatively soft or hard. To interpret their results, Wooten and DeSantis compared the microscopic wear patterns on Archaeotherium teeth with those of modern mammals whose diets are well known, including bears, wolves, hyenas, peccaries, and cheetahs.
The results revealed a surprising pattern: smaller-bodied and larger-bodied Archaeotherium appear to have been eating very different foods. Smaller-bodied individuals showed tooth textures most similar to cheetahs – animals that primarily consume flesh while actively avoiding hard materials like bone. This suggests that smaller Archaeotherium may have been consuming large amounts of soft foods such as meat. In contrast, larger-bodied forms showed wear patterns more similar to hyenas, whose diets include crushing hard materials such as bone.
“My original hypothesis was that all Archaeotherium were eating hard foods and scavenging,” Wooten explained. “I was very surprised initially by the results because, without breaking them down by size, they overall had fairly soft-looking textures. After looking at different size classes, I discovered the size-driven dietary partitioning.”
Wooten points to fossil evidence of bite marks attributed to Archaeotherium on the bones of the ancient camel Poebrotherium as additional evidence that at least some forms were active meat eaters.
Perhaps most intriguing is that the pattern observed in Archaeotherium appears unusual compared with modern mammals. Today, smaller carnivores often consume harder foods than larger competitors because they are pushed toward less desirable food resources. Coyotes, for example, scavenge and consume harder foods more frequently than wolves. Similarly, black bears rely more heavily on harder foods than larger brown bears.
Archaeotherium seems to show the opposite pattern. According to Wooten, this ecological reversal raises fascinating evolutionary questions. Why did this pattern evolve in Archaeotherium? Did other extinct mammals partition food resources in similar ways? And could this flexibility have helped these animals persist for roughly 17 million years through periods of major environmental and climatic change?
Archaeotherium also challenges assumptions about how extinct animals are studied more broadly. The researchers argue that fossil species are often treated as ecological “monoliths,” with scientists assuming all individuals within a genus behaved similarly. The new findings suggest that different forms of Archaeotherium may have occupied distinct ecological niches instead.
Rather than occupying a single ecological role, Archaeotherium species may have succeeded for millions of years by adapting to multiple dietary strategies across changing ancient environments.
Citation: Wooten, B., DeSantis, L.R.G. 2026. Palaeogeography, Palaeoclimatology, Palaeoecology.
Funding statement: This research was supported and funded by the Evolutionary Studies Initiative at 91Թ, the Paleontological Society President’s Student Research Award (MAPS Outstanding Research Award), and the National Science Foundation Graduate Research Fellowship Program (Grant No. 1937963 and 2444112).