Scientists were able to identify a near-complete skeleton of a 4.8-meter-long dolphin ancestor that lived in what is today South Carolina, the United States, during the oligocene era, about 25 million years ago.
Unique features
This is the top predator dolphin - the animal that is at the top of the food chain and has no natural predators - the first to rely on echo positioning, as dolphins and whales rely on echo-based sound systems for positioning.
This dolphin is large in size, has large fangs like teeth, and shows the ability to feed and hunt very quickly like the orca whale, a serrated killer whale that belongs to the oceanic dolphin family, and is the largest member of it.
The importance of this discovery is that it helps scientists better understand how unique features such as fins and tail propel for two types of whales, namely serrated whales, contain 73 species, and whale whales are characterized by the presence of spherical plates that filter the food in their mouths.
In the 1990 ankylorhiza tiedemani ancestral dolphin skeleton was found, but its classification was incorrect at the beginning, and was the first time that a near-complete skeleton had been analyzed, which would assist in a more comprehensive understanding of the rank of whales.
The results of the study of this structure were published in the Current Biology journal and were covered by a report by the Science Alert website on July 12.
Predatory and farewell
One of the basic data for this discovery is that many of the features of the skeleton - including the shape of the skull, tail, fin bones and tooth shape in both cogs and balloons - have evolved in parallel and separately from each other due to the similarity of the aquatic environments in which they live.
Robert Bosenker, a specialist in paleontology at College of Charlston in South Carolina, notes that the degree of similarity between ballet whales and dolphins in all of their adaptive swimming capabilities occurred surprisingly independently.
About 23 million years ago the era of the giant dolphin ended as an ancient predator with its extinction, and since then whales and other dolphins have alternated, but today the Orca whale is considered the only whale that depends on echo to determine sites, and it is also one of the top predators.
The splendor of this discovery is not based on the belief that the fierce Orca whale and the modern gentle dolphin are closely related, but that the extinct dolphin Anchloriza was feeding tens of millions of years ago in a manner similar to the Orca whale today.
"Whales and dolphins have a long and complex history that modern species do not show," Busenker says. "The fossil record has shown this long, winding path, and fossils like ankyloriza can help understand what happened."
"Since the filtration group of nutrients (such as Balinese whales) and echo-based groups evolved in the early Oligocene, and since the locations of marine mammals were rare at that time in the world, the Charleston fossils provide the most complete window of development," Busenker adds. Early for these groups. "