Scientists have rediscovered a set of giant fossil bones that belonged to the famous prehistoric shark, the megalodon.
The fossils had been missing for decades, but their return has helped confirm that this ancient predator may have grown up to 24.3 meters (80 feet) long, making it one of the largest animals that ever lived.
The fossil bones were first found in a clay pit in Denmark in the late 1970s. They were studied in the early 1980s and then stored in a museum collection.
However, after being moved to a different location, the fossils were accidentally misplaced. For many years, scientists only had old photographs of them.
Everything changed in the late 2010s when a museum staff member noticed several forgotten boxes filled with fossils.
The boxes contained the long-lost megalodon vertebrae, or backbone bones, which had been missing for nearly 40 years.
The rediscovered fossils are around 10.8 million years old. They are especially important because they were the original fossils used to estimate the largest known size of a megalodon. The biggest vertebra measures 23 centimeters (9 inches) across.
According to the researchers, these are not only the largest shark vertebrae ever found but also the largest fish vertebrae ever discovered.
Unlike most animals, sharks have skeletons made mainly of cartilage rather than bone. Cartilage does not fossilize easily, so complete megalodon skeletons have never been found. Scientists usually study the shark’s large fossil teeth, but vertebrae provide valuable clues about its size and growth.
The research team also used high-resolution micro-CT scanning to study growth rings inside the vertebrae. These rings are similar to the rings found in tree trunks and may represent one year of growth each. The scans showed that this megalodon was at least 64 years old when it died. Based on its growth pattern, researchers believe it may have been able to live as long as 96 years.
Another surprising discovery came from the rocks surrounding the vertebrae. The scientists found tiny scales and parts of the gills from a basking shark, a huge but harmless filter-feeding shark that still lives today. Because these remains were mixed closely with the megalodon fossils, the researchers believe they were likely the giant shark’s last meal. This is the first direct fossil evidence of what a megalodon may have eaten.
The Danish fossil site also marks the northernmost confirmed location where megalodon fossils have been found. Interestingly, scientists have noticed that the largest megalodon fossils are often discovered in cooler regions rather than warmer ones.
Although future discoveries could improve scientists’ understanding of this ancient giant, researchers say that an estimated length of 24.3 meters, or about 80 feet, is currently the largest size that can be scientifically supported for the mighty megalodon.
