Researchers from the prestigious Spanish Institute of Oceanography (IEO) have discovered off the coasts of La Graciosa a series of fossils belonging to the megalodon, the largest shark ever to have existed on our planet. These enormous marine predators reached a length of up to 20 metres and an astonishing weight of 100 tonnes.
The fossils found, which correspond to specimens of the species Otodus (Megaselachus) megalodon, include not only remains of this imposing shark but also fossilised fragments of other extinct sharks, as well as bones of marine mammals, such as the skull and ribs of a sirenian, a group of marine animals that includes manatees and dugongs. Fossilised whale bones were also found, pointing to the richness of marine life that existed in this region in past ages.
Although the fossils were discovered in October 2012, their precise identification took place recently at the IEO's Canary Islands Oceanographic Centre, thanks to the joint work of two leading scientists: Pedro J. Pascual Alayón, a marine biologist at the IEO, and Franco Cigala Fulgosi, professor of palaeontology and palaeoecology at the University of Parma in Italy.
The underwater palaeontological site was found at a depth of more than 1,000 metres, near the seamount known as the Banco de Concepción, located to the north of the island of La Graciosa. According to marine biologist Pedro J. Pascual, this discovery is of great scientific relevance, as it provides unique information about the ancient marine landscape of the Canary Islands as they were emerging from the ocean floor, during the Miocene, between 23 and 5 million years ago.
This astonishing find confirms that during that period of history the waters of the Canary Islands were home to, and served as hunting and breeding grounds for, the greatest marine predator of all time: Otodus (Megaselachus) megalodon, commonly known as the megalodon. These giants reached colossal sizes and their diet consisted of whales, dolphins, seals and large fish.
Enormous marine richness
According to the scientists, this prehistoric shark, now a fossil, inhabited our oceans for approximately 20 million years, from the Miocene to the Pliocene, until just 2 million years ago. Its dental characteristics reveal that it fed on large prey, such as whales, dolphins, seals and other marine mammals, as well as turtles and large fish. It was also a cosmopolitan species, spread across every ocean, and it undertook long-distance migrations.
The fossil record also suggests that smaller megalodons were more common in coastal areas, while the larger specimens were found in open waters far from the coast. This distribution could be related to the choice of certain coastal areas or islands as breeding and nursery grounds, where these enormous species found abundant amounts of food for their development.
Pedro J. Pascual stated that “the presence of this superpredator, as well as of other shark species occupying the highest levels of marine food webs, demonstrates the existence of large amounts of food, such as whales, seals, sirenians and shoals of fish, in Canarian waters at that moment in the Earth's history”.
As well as the impact of the megalodon discovery, the finding of fossilised sirenian remains in the Canary Islands is a first. The presence of these marine mammals had never before been recorded in the Canary Islands, which provides valuable information about the ecosystem and the climate that existed during the earliest stages of the archipelago's formation.
This fascinating discovery sheds light on the marine past of the Canary Islands and invites us to reflect on the richness and diversity of life that has inhabited our oceans throughout history.