Scientists rediscover lost Megalodon fossils—and reveal a 79-foot giant

Museums, generally regarded as repositories of global cultural and scientific treasures, occasionally house specimens that disappear without a trace. Fortunately, they can also resurface, as demonstrated by a recent study. This study reveals the vertebrae of the legendary predatory shark, once known as Megalodon (now officially classified as Otodus megalodon), hidden on a museum shelf for decades after being misplaced.

The research delves into the growth and size of this formidable shark, which roamed the seas between 15 and 3.5 million years ago. The study supports earlier estimations suggesting these sharks could have extended beyond 24 meters (79 feet) in length. To grasp the enormity of this, consider that even the most exaggerated sharks in the cinematic portrayal of Jaws never surpassed a length of 10.5 meters (34 feet). Such were the colossal dimensions of these prehistoric creatures.

The findings are derived from an examination of several 11-million-year-old vertebrae from a single animal discovered in Denmark. Despite jaws and teeth being the most iconic features of sharks, shark skeletons predominantly consist of cartilage, making vertebrae scarce and highly valuable. As such, these vertebrae provide a more accurate representation of the shark's dimensions.

Among them, the largest known vertebra measures 23 cm (9 inches) in diameter, making it the most substantial among any O megalodon specimens. These vital specimens were presumed lost during a relocation from the Geological Museum of Copenhagen (now part of the Natural History Museum of Denmark) to the Museum of Southern Jutland in 1989.

The scientific records of these vertebrae were limited to old photographs and descriptions. However, a couple of these vertebrae have resurfaced, inconspicuously sitting on a museum shelf for decades, enabling the recent study.

This discovery also allows for the estimation that a newborn O megalodon likely measured 3.6 meters (12 feet) in length and could live for nearly a century. The study underscores the unpredictable ways in which fossils can vanish from museum collections. The most apparent reasons include conflicts, such as the loss of dinosaur fossils during World War II.

The Spinosaurus, for instance, was destroyed in Munich by an allied bombing raid in 1944. Additionally, specimens, including parts of the early dinosaur Thecodontosaurus, were lost in Bristol following an Axis raid in 1940. These incidents were not isolated; they were not the first losses from wartime actions. In 1916, the Canadian ship SS Mount Temple was sunk by a German vessel, carrying a cargo of dinosaur fossils from Alberta intended for relocation to the UK.

Although the cargo list is ambiguous, we remain uncertain about the specific fossils on board. Indirect causes can also lead to fossil losses. In 1941, the Chinese attempted to transport up to 40 specimens of Homo erectus, one of our earliest relatives with human-like features, to the US to safeguard these valuable hominid fossils from Japanese forces.

Unfortunately, the vessel carrying them was sunk, and the fossils might have been lost at sea. Other scenarios involve loss due to negligence or mishaps. A giant sauropod dinosaur, similar to Diplodocus, was initially described by US paleontologist Ed Cope in 1877 as Amphicoelias fragillimus, based on a single, incomplete, fragile vertebra.

The vertebra's measurements varied over time, making its true size unclear. When Cope passed away, his collection was sold to the American Museum of Natural History, but the vertebra could not be located. Due to its fragility, it might have disintegrated on the shelf and been overlooked or discarded. Museums, despite their extensive collections, are susceptible to losses.

With an estimated 80 million objects in the London Natural History Museum alone, it is inevitable that some specimens may go missing. As a museum employee, I have witnessed lost specimens resurface, such as when a colleague found a dinosaur skull and pterosaur skeleton misplaced on the wrong shelf. However, there are instances of deliberate moves by researchers to conceal specimens from other scientists, and occasionally, specimens are stolen from collections.

Natural disasters and accidents can also obliterate historical records. The 2011 Fukushima earthquake and tsunami in Japan inflicted significant damage on the nearby Iwaki museum, affecting some of their fossil collections. In 2018, the Nation Museum of Brazil in Rio de Janeiro faced a fire, resulting in the loss of numerous fossil specimens on display.

Despite these challenges, museums remain valuable guardians of specimens. Millions and millions of fossils have been preserved in institutions around the world for decades and even centuries. Accidents and malicious actions are inevitable, but fortunately, these specimens occasionally resurface, providing exciting opportunities for new research.