An international group of paleontologists uncovered the most ancient known huge predatory shark belonging to the lineage of modern lamniforms—a group that presently includes great white sharks. This marine predator lived near the coasts of modern northern Australia approximately 115 million years ago—long before the appearance of whales, megalodon, and most other oceanic giants. The research is published in the journal Communications Biology (ComBio).
Paleontologists discovered the oldest giant predatory shark off the Australian coastline.
This concerns a representative of the Cardabiodontidae family—ancient mega-predatory sharks previously known from discoveries no older than 100 million years. The new data push back the emergence of these marine super-predators by 15 million years. The fossils were found on the coastline near the city of Darwin, in a region that constituted the floor of an ancient ocean connecting Gondwana and Laurasia during the Cretaceous period. The area is already known for remains of plesiosaurs and ichthyosaurs; however, the new vertebrae suggest the existence of an even larger predator.
Researchers examined five vertebrae, each approximately 12 centimeters in diameter. The specimens were initially found back in the late 1980s and 1990s, but remained unanalyzed in detail for a long time. Re-examination allowed for a reconsideration of their significance. According to scientists’ estimates, the shark’s length could have reached 8 meters, whereas modern great white sharks rarely exceed 6 meters. This refers to an ancestor that lived during the era of the early evolutionary ascent of lamniforms. The skeletons of sharks are composed of cartilage, which does not preserve well in fossilized states; therefore, most finds consist of teeth, which sharks shed throughout their lives. Vertebrae, however, provide a more reliable estimation of body size. To reconstruct the appearance of the ancient predator, scientists utilized data from modern ichthyology, computed tomography, mathematical models, and comparisons with currently living sharks. In their view, the ancient shark looked almost like a modern basking shark.
The work demonstrated that the “shark” body shape proved evolutionarily successful. By the middle of the Cretaceous period, lamniforms had reached the peaks of the food chain, and the fundamental plan of their structure has barely changed since then. Scientists speculate that similar giants might have inhabited other parts of the ancient sea. Now, they plan to search for comparable findings across the globe.
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