The extinct Otodus megalodon, or “megalodon,” remains an iconic apex predator, known for its massive size and fearsome teeth. Growing up to 65 feet in length, the megatooth shark preyed on large marine animals, such as whales and other sharks. Its serrated, blade-like teeth were ideal for such hunting, and evidence of megalodon’s predatory behavior is abundant in the fossil record. However, fossils of megalodon teeth bearing bite marks from other megalodon teeth are exceedingly rare.
In a study recently published in Acta Palaeontologica Polonica, researchers from the Calvert Marine Museum and St. Mary’s College of Maryland examined four megalodon teeth that show bite marks inflicted by other megalodon teeth. These marks appear as shallow, parallel grooves etched into the teeth, caused by the serrated edges of another tooth striking them. Although these bite marks provide a glimpse into megalodon behavior, the exact circumstances under which they were made remain uncertain.
The simplest explanation is that the bite marks occurred when the teeth of a megalodon struck each other during a bite. However, this scenario is unlikely due to the anatomy of lamniform sharks, the group to which megalodon belongs. Lamniform sharks have an upper jaw that protrudes far beyond the lower jaw, making direct contact between upper and lower teeth improbable. A tooth would need to be dislodged or out of place for such an impact to occur.
Another plausible scenario involves a megalodon tooth being knocked loose but remaining in the shark’s mouth. During a subsequent bite, this loose tooth could have been struck by another occluding tooth, resulting in the observed marks.
A third possibility ties the bite marks to predatory or scavenging events. A dislodged megalodon tooth embedded in the prey’s body—perhaps during an attack on a whale—could have been struck by another tooth during a later bite. Megalodon’s bite force, calculated to be more than ten times that of the modern great white shark, would certainly be capable of producing these marks.
The study also explores the idea of aggression or cannibalism among megalodon sharks. Territorial disputes, competition over mates, or acts of cannibalism—either active predation or scavenging—may have led to jaw-to-jaw bites. Modern great white sharks, relatives of megalodon, are known to exhibit similar behaviors, including jaw-to-jaw aggression and cannibalism. In these scenarios, one megalodon might have bitten the jaws of its rival or scavenged a carcass, leaving marks on the teeth.
While the exact events that caused these bite marks remain speculative, the rarity of such fossils underscores their significance. These findings offer a unique glimpse into the behaviors of one of history’s most formidable predators, sparking curiosity and inspiring further study of the prehistoric marine world.