On top of that, when analyzing the spikes, the team noticed a distinct pattern. The wear was not uniform. The right edge of the jaw was consistently more worn, chipped, and scratched than the left. The team concluded that this asymmetry was not an accident but rather evidence of lateralized behavior. It’s a trend we see in modern octopuses, which often prefer a specific side of their body or a particular eye when performing complex tasks.
In biology, lateralized behavior is usually linked to a specialized and very sophisticated nervous system. “Of course, we can’t directly measure intelligence from a fossil,” Iba said. “But the asymmetrical wear suggests that these animals may also have had advanced, individualized hunting behavior, similar in some ways to modern octopuses.”
Not only were they huge and powerful. They were probably smart.
The evolutionary arms race
A highly intelligent 19-meter-long cephalopod that actively hunts and crushes its prey suggests that the Cretaceous evolutionary arms race was not completely dominated by vertebrates. By shedding heavy shells like those seen in early nautiloids and ammonites, the ancestors of modern octopuses traded passive defense for active offense. They gained explosive swimming speed, vast improvements in vision, and the neurological capacity necessary for advanced cognition.
“Our study highlights convergent evolution. Vertebrates and cephalopods have very different evolutionary origins, but both evolved into large, intelligent marine predators with powerful jaws, flexible bodies, high mobility and advanced behavior,” Iba said. He points out that Cretaceous marine ecosystems were probably much more complex than we thought.
Iba also hopes that the Digital Fossil Mining technique can be used to learn more about this complexity. “One important direction is to apply digital fossil mining to many more fossil-bearing rocks,” he told Ars. “This approach allows us to discover organisms and structures that were previously almost invisible in the fossil record.” According to him, the technique is especially important for animals such as octopuses and squid, which rarely fossilize.
Ultimately, the team wants to piece together a more complete history of cephalopods. “More broadly, our goal is to reveal the hidden components of ancient ecosystems and build a much more complete picture of how past ecosystems actually functioned,” Iba said.
Science, 2026. DOI: 10.1126/ciencia.aea6285
