2024-04-02 14:32:54
The pebanista snorted It is the largest river dolphin on Earth that lived 16 million years ago, described in the article in the scientific journal Science Advances, published yesterday, March 20. Their fossils can now be seen in the Natural History Museum of the Universidad Nacional Mayor de San Marcos (UNMSM). What was Pebanista like and why is he so amazing to the scientific community?
A predator of his time
From the skull bones found, the team of researchers suggests that it is the largest freshwater dolphin ever recorded. It is estimated that its size ranged between 2.8 and 3.5 meters long, which places it above the length of today’s river dolphins.
As for the details on his head, according to the study, he stands out for having a long and strong snout, big teethbony prominences over the eyes and ample space for the jaw muscles.
“Such a large body size, also recorded in other inhabitants of the Proto-Amazon (i.e., fish and crocodiles), could be attributed to the great availability of resources in Proto-Amazonian ecosystems,” the publication in Science Advances indicates.
Likewise, Rodolfo Salas, member of the team responsible for the discovery, affirms that it is a predatory species in a time of great abundance of fish in aquatic landscapes of the jungle of Peru.
“What we can say is that it competed with long snouted crocodiles which also lived in the Amazon, are called gharials. Coincidentally, now gaviales They live in Asia. That is super interesting because crocodiles and dolphins that lived in the Amazon millions of years ago have survived in Asia,” Salas tells La República.
Relative of a dolphin who lives far away today
One of the dolphin’s most impressive features is its familiarity with a dolphin that today swims in the distant waters of South Asia. “Our phylogenetic analyzes unambiguously recovered Pebanista as the sister taxon of Platanithus constituting the closest known relative of the river dolphins existing in South Asia,” the study reads.
“This closeness that (both species of dolphins) have is very strong and creates a problem because the big question we have is how does an animal like this end up in the proto-Peruvian Amazon? That is the big question that this discovery has left us and it makes us understand that we know nothing about the evolution of the Amazon in South America,” comments Aldo Benites-Palomino, who led the research.
“From today’s perspective, these dolphins are very far away. But, in the past, dolphins in this group were inhabiting marine environments. And, then, they were widely distributed in all the oceans”, explains Rodolfo Salas about a possible explanation of the relationship.
“The marine ancestor of the Pebanista and the Platanista was living in all oceans and surely made incursions into freshwater river environments, both in the Amazon and in India. The way people lived in Pebanista Peru became extinct, but Platanista survived to this day,” he adds.
Although the two species of dolphin live far apart, they currently share a common origin, according to research. Photo: Modified from Benites-Palomino et al.
The truth is that there are still several questions in this regard that they will try to answer with future planned expeditions, according to what the researchers told this medium.
Why is it the largest dolphin in the world?
Although only part of the skeleton of Pebanista yacuruna is known, it is scientifically estimated to be the largest river dolphin on Earth. How is it possible? Salas affirms that this is because it is possible to have greater certainty about the dimensions of the animal because the complete skull is available.
According to the expert, this case is different from that of Perucetus colosus. In this regard, foreign scientists formulated a recent research article that contradicts the first study where it is described as the heaviest mammal on Earth.
“In the case of Perucetus, there is a large amount of uncertainty because we have some vertebrae. In this case, we have a skull and there are many dolphins on the planet, currently, with which we can compare,” he explains.
“The pattern of the dolphins hasn’t changed much. In the case of Perucetus it is a totally new pattern for biology, we know nothing. In the case of the Pebanista, we have the complete skull and we have current representatives with a similar morphology, so we can have greater certainty of the dimensions,” he states.