A team of oceanographers has reported the first results of examining a megalodon tooth in situ, that is, in a natural environment. It remained untouched at a depth of more than three kilometers for at least 3.5 million years.

The expedition team found a megalodon tooth at a depth of 3,090 meters in the Pacific Ocean, about 350 kilometers southeast of Johnston Atoll between Hawaii and the Marshall Islands. Taking into account the well-preserved serrations of the cutting edges, scientists assumed that the sample, although it had a significant age of at least 3.5 million years, did not move anywhere and lay at the bottom until June 23, 2022, when people found it. . This was reported by oceanologists from the University of Rhode Island (USA) and the South African Aquatic Biodiversity Institute (South Africa). His articles were published in the magazine Historical Biology .

a type of shark Otodus megalodon – one of the largest known marine predators, whose length can reach 20 meters. The causes of the extinction, which occurred during the transition from the early Pliocene to the late Pliocene (about 3.6 million years ago), are still in doubt. Scientists suggest that changes in oceanographic conditions and competition for food with the great white shark play a role.

When the tooth formed 118 million years ago (Early Cretaceous), it stood on an isolated seamount located in a geologically complex location between the Central Pacific Ridge and the Line Islands Ridge to the west.

“The location where the sample was taken was a relatively flat area at the top of the ridge, covered with minerals of varying sizes. In between were areas of fine-grained sediments. In an area with smaller nodules, a remotely operated underwater vehicle (ROV) collected bottom sediment samples using a shovel.” “Sample NA141-006-01 consisted of smaller nodules, sandy sediment and a tooth. Further examination of the high-resolution video taken by the ROV revealed that the cutting edge of the tooth was protruding from the sediment and the tooth itself was protruding vertically into the sand,” he said.

The find reached a height of 68 millimeters and a width of 63.3 millimeters. Only the triangular crown has survived to this day, the tip is broken off, and the cutting edges on both sides retain a clear serration. Only the outer layer of the enamel was petrified, all damaged areas and the base of the tooth were covered with a dark manganese crust.

fossil teeth Otodus megalodon It is found everywhere (this is explained by the migration of megalodons), but mostly in sediments accessible from land. Observation in placethat is, “in situ”, “in the natural environment” researchers have not yet studied. It was even possible for a remote-controlled underwater vehicle to photograph the sample before taking it away.

Two years ago, scientists from the University of Bristol in Great Britain, using engineering methods of digital modelling, discovered that the megalodon’s teeth were a byproduct of growth, not an adaptation to eating habits. They coped with their task no better than the teeth of the smaller ancestors of these sharks.