Evidence from New Mexico

Recent discoveries in New Mexico's San Juan Basin have provided compelling evidence that tyrannosaurs occasionally practiced cannibalism. Researchers uncovered three partial bones from both adult and juvenile tyrannosaurs, all showing clear bite marks and feeding traces left by another tyrannosaur. The bones include an isolated anterior left dentary (a bone from the lower jaw), a proximal caudal centrum (tail vertebra), and an isolated right femur (thigh bone).

The dentary showed signs of healing around the bite marks, indicating the animal was still alive when attacked. In contrast, the caudal centrum and femur lacked any healing signs, suggesting they were bitten post-mortem. While the exact genus of the discovered bones remains unidentified, they indicate that tyrannosaurs in this region consumed not only their common prey—like horned ceratopsians or duckbilled hadrosaurs—but also fellow tyrannosaurs.

Confirming Previous Findings

These recent findings are consistent with earlier research. In 2010, paleontologist Nickolas Longrich noted four Tyrannosaurus rex bones that exhibited gouges and bite marks. Similarly, in 2015, a limb bone found in Wyoming displayed injuries consistent with large serrated teeth, which could only have been inflicted by another T.rex. Given that the T.rex was the sole large carnivore of its time, this evidence strongly suggests intra-species predation.

Did Tyrannosaurs Uniquely Engage in Cannibalism?

Hans-Dieter Sues, a curator at the National Museum of Natural History, asserts that cannibalism among carnivores is not unusual: “Meat-eaters of all kinds consume dead animals, which are simply meat available for consumption. Even omnivorous pigs will eat other pigs.” Thus, the behavior of tyrannosaurs is not remarkable within the broader context of carnivorous behavior.

Epilogue: Cannibalism in Nature

Despite its gruesome nature, cannibalism is a common behavior among many modern predators, such as crocodiles and Komodo dragons. Evidence suggests that tyrannosaurs were also opportunistic feeders, willing to consume members of their own species when the opportunity arose. This brutal trait likely contributed to their dominance at the top of the prehistoric food chain.

To explore further into the paleobiology of Tyrannosaurus, check out the article below:

Note

In this article, the term ‘tyrannosaurs’ refers to members of the Tyrannosauridae family, which includes genera such as Lythronax, Albertosaurus, Daspletosaurus, and Tyrannosaurus itself.

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