The giant sharks of antiquity - the megalodons - could have disappeared, unable to withstand the competition with smaller, but nimble white sharks.
Extinct between 2, 5 and three million years ago, megalodons are considered one of the largest fish that have ever existed on Earth. According to some estimates, they could reach 15 meters in length and weighed over 35 tons. However, the exact reason for the disappearance of these giant sharks remains a big mystery.
It is believed that cetaceans and more advanced predators that appeared in the Pliocene, with which the megalodons could not compete, may be "to blame" for this. Even hypotheses are put forward linking their death with a distant cosmic catastrophe. The authors of the new work, published in the Peer Journal, propose to make a small revolution in this topic, "postponing" the extinction of megalodons for 3, 6 years ago and blaming their close relatives for this.
Great white sharks are one of the largest predators of the modern Earth, but before they reached even larger sizes. Despite this, they remained several times smaller than megalodons. Judging by the data of the fossil record, they appeared about six million years ago, but finally "took shape" and captured vast areas only two million years later. It was this relatively short period - roughly between four and 3.6 million years ago - in which megalodons and great white sharks competed, that the ancient giants could not stand the competition with smaller, but more adapted newcomers.
A new, more thorough analysis of the fossils and previous works allowed the authors to confidently assume that later 3, 6 million years ago in the territory of the present-day Pacific Ocean, the formerly prosperous Otodus megalodon practically disappeared. The main competition could unfold between the great white sharks that had spread here and the juveniles of megalodons, which had approximately the same size and food base: here more advanced relatives left them no chance.