An ancient ancestor of the great white shark has been discovered, known to have torn its prey apart with jaws the size of a human hand 9 million years ago.

The ocean covers more than half of the Earth's surface and is home to an incredible number of species: some have thrived in the depths of the water for millions of years, while others have long since gone extinct. Despite its vast coverage, the ocean remains the least explored place on Earth. Fortunately for us, with each marine expedition, we uncover more secrets of the ocean, reports GMA News Online.

This week, paleontologists in Peru unveiled a fossil of an astonishing marine species — a relative of the great white shark that lived 9 million years ago. This gigantic predator once roamed the waters of the southern Pacific Ocean, feeding on sardines.

According to co-author of the study, engineer Cesar Augusto Chacaltana from the Peruvian Geological and Mining Institute, the nearly complete fossil of the mackerel shark (Cosmopolitodus Hastalis) was discovered about 235 kilometers south of Lima in the Pisco basin of Peru — a hot desert region known for frequent discoveries of ancient marine species.

It is worth noting that scientists previously suggested that the mackerel shark is an ancestor of the great white shark. Currently, the species is considered extinct; however, in the past, the enormous teeth of this species reached 8.9 centimeters, and adults could grow up to 7 meters long.

The authors of the study emphasize that the remains they found demonstrate "exceptional fossilization." The remains of the ancient species were presented in several glass blocks — one of which also showcased a shark jaw with sharp teeth.

According to co-author of the study, paleontologist Mario Urbina, there are not many complete shark fossils in the modern world. During their research, scientists discovered numerous sardine remains inside the predator's stomach. Since anchovies did not exist when the shark was roaming the open seas and oceans, sardines likely constituted the primary food source for marine predators.

Interestingly, earlier last year, paleontologists also presented a fossil of a young crocodile that lived over 10 million years ago off the central coast of Peru. Even earlier last year, scientists found and showcased the fossilized skull of the largest river dolphin, believed to have lived in the Amazon about 16 million years ago.