An important, albeit controversial, episode has been added to the developmental history of cetaceans. Scientists have succeeded in reaching a consensus on the fossil skeleton of the dolphin ancestor that lived 23 million years ago in the oceans of what is now South Carolina. They determined that he belongs to the species Ankylorhiza tiedemani - the largest, toothy and aggressive dolphins in the history of our planet.
The skeleton of an ancient dolphin was found back in the 1990s, but initially it was incorrectly identified - and this is not accidental. Ankylorhiza tiedemani dolphins resembled modern individuals no more than the ancient Neanderthal of modern humans. Huge, almost 5 m long, with large teeth, they were at the top of the food chain in the ocean of those distant times. Largely due to the fact that they were the first in history among predators to develop the ability to echolocate.
Today all dolphin species have this biological echo sounder, as well as killer whales, which occupy the top of the food chain among marine mammals. And 25 million years ago, on the edge of extinction of Ankylorhiza tiedemani, this property allowed dolphins to further distance themselves from whales and finally stop competing for food. Modern baleen whales feed on plankton, and dolphins feed on fish, which allows them to peacefully coexist in the same ecosystem.
And in the period 23-35 million years ago, everything was different. Scientists were surprised to note that dolphins and whales, independently of each other during the evolutionary process, developed identical traits that are beneficial for life at sea. For example, the structure of the caudal fin and the shape of the skull. This is important - they did not inherit these properties from a common ancestor, but received them on their own, striving to dominate the world's oceans.