The researchers at the University of Otago discovered ancient fossils, which reportedly depicted facts regarding baleen whales evolution. The baleen whale is known as the Earth’s largest animal that existed in the Antarctica Sea approximately thirty-four million years before. The discovered fossil has given researchers new clues regarding baleen whales.
The researchers discovered the skull of what is called Llanocetus denticrenatus that is believed to be the “second-oldest baleen whale” on the planet. After a thorough analysis of the received fossil, the scientists have revealed that the ancient whales were devoid of any baleen. Their mouth rather had well-developed teeth with the help of which they bit their prey.
Dr. Felix Marx who is a paleontologist at the Royal Belgian Institute of Natural Sciences said in a statement that the early Llanocetus denticrenatus is the ancestor of the modern gentle blue whales and humpbacks. He added that unlike the present whales that have baleen in their mouth, the ancestor had teeth and was a frightening predator. Dr. R. Ewan Fordyce at the University of Otago in New Zealand said that until the discovery it was believed that “filter feeding” initially came into existence when the whales still possessed teeth. Fordyce added further that the Llanocetus denticrenatus suggested that the belief was not actually true. Dr. Marx told that the Llanocetus denticrenatus possessed huge gums and developed teeth rather than a filter. He further told that the huge body length of the creature measured to near about eight meters.
The researchers explained that just like the present day whales, the ancestors possessed unique groves at the roof of their mouths that generally consisted of blood vessels, which functioned by supplying the baleen. Nevertheless, in the ancient whales, these grooves were seen clustered around the tooth sockets, just at the point where the baleen would have had no use. As per the study, the huge gums in the ancient whales eventually turned more complex and ultimately transformed into baleens.
Dr. Fordyce explained that from the study they believe that the climate condition influenced the history of the whales heavily. He said that more specifically, the transformation from tropical temperatures to much cooler temperatures played a major role in the change. He further demonstrated that when the temperature became cooler, a transformation in the food and nutrition cycle took place and that might have been the reason behind the evolution of baleens. The authors of the study said that the baleen may have evolved to help in keeping the smaller preys more effectively in the mouth.