Post by Benfxmth on Aug 2, 2023 15:09:19 GMT -5
The fossil record of cetaceans documents how terrestrial animals acquired extreme adaptations and transitioned to a fully aquatic lifestyle1,2. In whales, this is associated with a substantial increase in maximum body size. Although an elongate body was acquired early in cetacean evolution3, the maximum body mass of baleen whales reflects a recent diversification that culminated in the blue whale4. More generally, hitherto known gigantism among aquatic tetrapods evolved within pelagic, active swimmers. Here we describe Perucetus colossus—a basilosaurid whale from the middle Eocene epoch of Peru. It displays, to our knowledge, the highest degree of bone mass increase known to date, an adaptation associated with shallow diving. The estimated skeletal mass of P. colossus exceeds that of any known mammal or aquatic vertebrate. We show that the bone structure specializations of aquatic mammals are reflected in the scaling of skeletal fraction (skeletal mass versus whole-body mass) across the entire disparity of amniotes. We use the skeletal fraction to estimate the body mass of P. colossus, which proves to be a contender for the title of heaviest animal on record. Cetacean peak body mass had already been reached around 30 million years before previously assumed, in a coastal context in which primary productivity was particularly high.
www.nature.com/articles/s41586-023-06381-1#Abs1
"In this corner, weighing up to 190 metric tons, is the blue whale. This behemoth still swimming in Earth’s oceans is the current titleholder for the heaviest animal to ever exist — living or dead.
And in this corner is the contender, a massive marine mammal that went extinct millions of years ago. Fossils of this ancient leviathan’s bones recently dug up from the deserts of Peru suggest it may have weighed up to 340 metric tons, challenging the blue whale’s status as the most massive ever in the animal kingdom.
When Alberto Collareta first laid eyes on the boulder-sized vertebrae of the extinct animal, he couldn’t believe what he was seeing. He wondered how a creature that large could even move around.
“I was in front of something unlike anything I had ever seen,” said Collareta, a University of Pisa researcher and co-author of a study published Wednesday in the journal Nature describing the freshly unearthed species of giant prehistoric whale.
Dubbed by its discoverers Perucetus colossus, or simply P. colossus, the titanic animal may not be just a record setter. P. colossus is also compelling scientists to reconsider their ideas about how animals are able to grow to gigantic sizes.
“This is another way in which you can get big,” said Hans Thewissen, a paleontologist and whale evolution expert at Northeast Ohio Medical University. With a body that looked vaguely like that of a manatee rather than a blue whale’s, it clearly did something different than other whales to maintain its huge mass.
But not everyone is convinced this colossus, while undoubtedly big, is truly more massive than a blue whale. The research team acknowledges their estimates for the animal’s body mass range widely, from 85 tons all the way up to 340 tons. The team exhumed only a partial skeleton without a skull, leading some scientists to say more fossils are needed before anyone names a new heavyweight champion of the animal kingdom.
But he added: “Clearly, it is really big.""
www.washingtonpost.com/climate-environment/2023/08/02/largest-animal-whale-p-colossus/
www.nature.com/articles/s41586-023-06381-1#Abs1
"In this corner, weighing up to 190 metric tons, is the blue whale. This behemoth still swimming in Earth’s oceans is the current titleholder for the heaviest animal to ever exist — living or dead.
And in this corner is the contender, a massive marine mammal that went extinct millions of years ago. Fossils of this ancient leviathan’s bones recently dug up from the deserts of Peru suggest it may have weighed up to 340 metric tons, challenging the blue whale’s status as the most massive ever in the animal kingdom.
When Alberto Collareta first laid eyes on the boulder-sized vertebrae of the extinct animal, he couldn’t believe what he was seeing. He wondered how a creature that large could even move around.
“I was in front of something unlike anything I had ever seen,” said Collareta, a University of Pisa researcher and co-author of a study published Wednesday in the journal Nature describing the freshly unearthed species of giant prehistoric whale.
Dubbed by its discoverers Perucetus colossus, or simply P. colossus, the titanic animal may not be just a record setter. P. colossus is also compelling scientists to reconsider their ideas about how animals are able to grow to gigantic sizes.
“This is another way in which you can get big,” said Hans Thewissen, a paleontologist and whale evolution expert at Northeast Ohio Medical University. With a body that looked vaguely like that of a manatee rather than a blue whale’s, it clearly did something different than other whales to maintain its huge mass.
But not everyone is convinced this colossus, while undoubtedly big, is truly more massive than a blue whale. The research team acknowledges their estimates for the animal’s body mass range widely, from 85 tons all the way up to 340 tons. The team exhumed only a partial skeleton without a skull, leading some scientists to say more fossils are needed before anyone names a new heavyweight champion of the animal kingdom.
But he added: “Clearly, it is really big.""
www.washingtonpost.com/climate-environment/2023/08/02/largest-animal-whale-p-colossus/
