Ancient Kraken-Like Octopus Reached 62 Feet, Largest Invertebrate Ever Discovered

New research reveals that the ancient oceans were once dominated by colossal, kraken-like octopuses that roamed between 72 and 100 million years ago. These invertebrates grew to staggering lengths, with the largest species, *Nanaimoteuthis haggarti*, reaching up to 62 feet (19 meters) in total length. This measurement rivals that of a sperm whale, which typically measures around 66 feet (20 meters), though it falls short of the blue whale's maximum span of 90 feet (27 meters). For context, this giant octopus would have been more than twice the height of an average human and significantly longer than an elephant, easily eclipsing the length of a standard London bus.

The discovery stems from a detailed re-examination of 15 large fossil jaws belonging to ancient octopus relatives. Scientists from Hokkaido University identified two distinct new species, noting that the sheer size of *N. haggarti* suggests it was the largest invertebrate ever described. Unlike many of their ancestors, these creatures evolved soft bodies rather than protective shells. Experts argue that this adaptation was not a disadvantage but a strategic advantage, granting them unprecedented mobility, superior vision, and advanced intelligence.

Evidence of their predatory nature is found in the fossilized remains. The jaws of *N. haggarti* show extensive wear, indicating they were active carnivores that routinely crushed hard shells and bones with powerful bites. Researchers observed that once-sharp features in juvenile jaws became blunted and rounded over time, while long scratches distributed across wide areas of the jaw reflect the dynamic use of the entire mouth for dismantling large prey. Notably, the wear was not uniform; the loss of jaw edges occurred more on one side than the other, suggesting the octopuses had a preferred side to chew on—a trait linked to highly developed brain function and cognition.

The second species identified, *Nanaimoteuthis jeletzkyi*, was also a predator but smaller, growing up to 26 feet (8 meters) in length. The findings indicate that these ancient cephalopods were not merely passive prey for apex dinosaurs like the ferocious mosasaur. Instead, they were highly active participants in shaping marine ecosystems, occupying ecological roles previously attributed only to large vertebrates such as sharks. As the study authors noted in the journal *Science*, "In the largest individuals, the jaws showed extensive wear with once-sharp features in small juveniles becoming blunted and rounded over time," confirming their status as formidable hunters.

Beyond their physical prowess, these creatures possessed behaviors that hint at complex mental lives. Like humans, octopuses transition between quiet sleep and an active stage resembling rapid eye movement (REM) sleep. When awake, they generate intricate skin patterns for camouflage and social signaling, such as warning off predators or communicating with one another. Researchers suggest that these skin patterns created while sleeping may indicate a capacity for dreaming, similar to humans.

The implications of this discovery extend beyond paleontology, offering a glimpse into a time when intelligence evolved independently of a vertebrate body plan. "Long after the rise of vertebrate top predators, octopuses evolved body plans capable of rivalling them, as demonstrated here," the team concluded. This revelation challenges our understanding of ancient marine food webs, showing that soft-bodied invertebrates could compete directly with the era's most dangerous vertebrate predators. However, the study also underscores a critical point: such immense size and capability existed only in a specific window of Earth's history, long before humans could ever observe or interact with these leviathans. The loss of these species represents a permanent gap in our knowledge of how intelligence and dominance can evolve in the absence of a hard shell or backbone.

New research reveals that ancient octopus-like creatures shared the same sleep cycles seen in modern animals, cycling through specific skin patterns while resting. However, their hunting capabilities were far more advanced than their modern descendants. A team from Sorbonne University in France utilized advanced three-dimensional imaging to examine a fossilized specimen dating back 164 million years. This ancient predator possessed extra-long suckers and hair-like strands on its arms, features it used to actively trap prey.

This stands in stark contrast to the modern-day vampire squid, which is not built for active hunting and instead feeds solely on organic drifting matter with less robust suckers. The ancient fossil showed clear evidence of muscular suckers located at the tips of two specialized, long dorsal arms, confirming it was a formidable hunter. To truly grasp the scale of this ancient beast, researchers depicted a human figure alongside the fossil, illustrating the sheer size of the colossal creature.

These findings highlight how limited and privileged access to such detailed information is for scientists studying deep time. The implications extend beyond simple biology; understanding the evolution of predatory strategies in these ancient cephalopods helps us reflect on the potential risks and impacts of such powerful hunters on their ancient ecosystems. As Dr. Jean-Yves Dutour, a paleontologist involved in the study, noted, seeing the evidence of active hunting in such an old specimen changes our view of the ocean's history. The discovery underscores how much we still have to learn about the creatures that once roamed our seas, reminding us that our current understanding is often just a glimpse into a vast, complex past.