Wednesday , October 16 2019
Home / argentina / Pendants, 33-million-year-old whale Evolutionary & # 39; Missing Link & # 39; it might be.

Pendants, 33-million-year-old whale Evolutionary & # 39; Missing Link & # 39; it might be.

A deep study of fossil found over four decades ago identified a new whale species: 33 million cetaceans, teeth and whales. His discovery can solve a long-term mystery with a filter-feeding whale, but scientists say the new study is not convincing.

submit Maiabalaena nesbittae, a new species of genus and the ancient species of whale. The whale's modern bronze, a 4.57-m long cetacean, was not due to teeth or whales (plates like hair are queues, because water filters small layers), it is based on suction nutrition.

Thus, Maiabalaena nesbittaeThe meaning of "Mother Whale" indicates an interval between ancient ballet turns and modern food filtering according to a new study published in today's Biology.

Today, whales can be divided into two main groups: whales, for example ankles and dolphins, and a whale (or mystic), such as whales, whales whales, blue whale and whale. The evolutionary invention of Baleen makes possible a permeable wind, allowing large sea whales to consume a lot of food every day.

Whales are the only mammals of the whale's evolution, but the origin of this eating strategy is not completely clear. Whales adapt to aquatic life after mammalian land.

With its sharp teeth, ancient Whales used to eat food. But the environment changed, as prey, so these whales had to take new nutritional strategies. In the end, this started to generate the whale feed filter.

How about whales to be whitened – keratin, what hair and nails, and what is a substance made, is a matter of controversy.

Some scientists have specified that ancient whales used their teeth to rise to the water, and this nutrition strategy directly affected whales. This theory was a direct success since last year's paleontologists at the University of Monash showed that the sharp teeth that occupy ancient whales could not be used as a filter, saying that the former whales were not in the filtration phase. Mediation, the species that have already been discovered have existed.

Part of the problem is that keratin is not well kept in the fossil record. For paleontologists who study ancient whales, this mystery is a seemingly endless search for a "missing link" between the flight of ancient animals and hegemony birds and self-propelling aircraft.

In the case of the whale, the paleontologist has discovered a midge of whale found in whales and a filter feed whale. Honeymoon discovery, baleenless Maiabalaena nesbittae This link might be very bad.

Partial skeleton Maiabalaena nesbittae, almost complete herb, was revealed in Oregon in the 1970s, and since she has lived in the national collection of Smithsonian. At this point, the exact fossil analysis was impossible with rock and other materials flooded.

Carlos Mauricio Peredo and the Natural History Museum of the University of Santiago, Carlos Mauricio Peredo, were the main authors of this new Fossil Science CT technology. If rocks were taken, the researchers identified the signals of the whale's whale and bale whale signals, that is, the whale's suspension had no adequate surface.

"The baleen whale of life has a large, wide roof in the mouth, and it also thickens the whale attachments," said Peredo in a statement. "Maiabalaena It does not. However, we can say that this fossil species did not say the teeth, and it might not be whales either. "

Other evidence suggests this animal as a filter filter. The muscles in the bones of the throat mean that they have powerful cheeks and retractive muscles. The bales valve will try to get water into the mouth and remove the fish and squid.

Thanks to this ability, these whales do not need more than necessary, so their teeth gradually disappear. The loss of the teeth and the origin of whales, the researchers argue, where, therefore, the separate events of evolution.

Because the whales that have been seized do not allow them to be discarded and absorbed, the researchers were forced by a changing environment. Maiabalaena During the period separated by the Eukene Oligo, about 33 million years ago. This was when the whales were critical, the continents were displaced and separated, and the ocean currents of the Antarctic crystallized oceans.

The geology of the planet changed, and so did the ocean environment – and its animals. Whales' predators were altered or disappeared, as they found new dam, due to transition from teeth and suction feeders, speculated by researchers. In the end, 5-7 million years later, about 26-28 million years ago, the toothless whales began to create birds to facilitate another transition.

"Overall, I think it's a good study, and I agree with its overall conclusions," said Felix G. Marx, a new paleontologist at the University of Monash said, saying Gizmodo. "Above all, Maiabalaena It seems appropriate in the middle of this transition, no teeth, and maybe no whales. "

Maybe not at all.

That is the key phrase here. As you can see, whales, which is made of soft tissue, is not very fossil. Usually, scientists can detect the presence of whales in fossils in search of blood clots. And, in fact, blood traces were detected Maiabalaena fossil The question, however, is whether these blood are always related to whale.

"The new study does not say, and argues that there are similar structures in the old oscillating varnish, which clearly did not filter," said Marx. "I agree, but that's still an interpretation, and nobody guesses anyone. Luckily, there's more to address this question, for example, to study how whats really stomachs."

The paleontologist at the University of Monasa, Alistair Evans, author of the 2017 study said, agrees with Marx's assessment that there is a fairly clear lack of this species, but the lack of whales is not so much.

"Because, in rare cases, it is fossilized, its presence can rarely be seen directly," said Evans. "As previously proposed – and [as this new paper] It provides more evidence – silver is not bones, because it can confirm the balance. So sadly, there is no strong proof of the absence of whales, but we did not find any such thing. "

Evans says that the effects of the new study are "quite reasonable," but it could also see other species of this species and similar species, if they were whales.

"I was glad to have found a planned fossil, but this evidence is not slam dunk slamming," added Evans.

So that's it Maiabalaena nesbittae Are we missing the link we are looking for? Perhaps yes, yes, but surely we will not recover more fossils.

[Current Biology]

Source link