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Fossil named after Burke Curator speaks of the story of evolution – GeekWire



Carlos Mauricio Peredo
Carlos Mauricio Peredo, a researcher at the National Natural History Museum, shows 33 million years of old fossil fuels recently classified under the name Maiabalaena nesbittae. (Smithsonian Photo)

The kit that lived 33 million years ago, when Oregon today was part of the ocean, got a new name by curator at the Burke Nature and Culture Museum in Seattle.

And Kit Elizabeth Nesbitt is Not Your Typical Kit: The Fossil Analysis, published in Current Biology on Nov. 29, suggests that Maiabalaena's disadvantages overlapped the gap between species of whales that had teeth and species having different oral cavities, a feeding mechanism known as baleen .

"For the first time, we can identify the origin of filter feeding, which is one of the major innovations in the history of whales," said co-author Nicholas Pyenson, curator of the National Natural History Museum of Fossil Sea Mammals and Associate Curator at the Burke Museum, said in a news release.

Fossil M. nesbittae was discovered in the seventies of the last century and has since been widely studied. But the rocket matrix and material surrounding the fossil has overshadowed many of its features, frustrating formal classification. Then Carlos Mauricio Peredo, a researcher at the National Museum of Natural History, thoroughly cleansed the fossil and reviewed it with the latest X-ray scanning technology.

A close look at the scandal showed M.'s misfortune's jaw no teeth. This in itself is not surprising: a kit, probably 15 feet long in life, lived in the time when some types of whales made an evolutionary transition from using the tooth to the use of baleen.

Baleen is the ranks of flexible, pollen-type plates, which types of whales, such as humpbacks and blue whales, are used to filter small spoils from giant gulps of ocean water. Feeding technique allows bales to bake daily consuming tons of food without bites or chewing.

What makes M. unbalanced is that her upper jaw was thin and narrow, making it inappropriate to support the baleen structure.

"The Life Baleen Kit has a large, wide roof in the mouth, and is also thick to create baleen attachments," said Peredo, who is the lead author of current biology studies. "Maiabalaena no, we can pretty much conclude that this fossil species has no teeth, and that's probably not even a baleen."

This would support the hypothesis that certain types of embryo have developed to exploit a feeding strategy that did not require either teeth or baleen.

Peredo and his colleagues say that muscle connections at M. bones indicate that they had strong cheeks and a tongue that can be drawn. They suggest the kit is capable of sucking large amounts of water in the mouth, taking small fish and squid in the process … without teeth. (The modern narwhal, which has only two vestigious teeth, uses a similar strategy.)

In this scenario, tooth loss places the stage for the appearance of baleal filtering structures millions of years later. The main factor for differentiating feeding strategies was probably the dramatic cooling of ocean waters during the transition from the Eocene to the Oligocene Epoch, about 34 million years ago.

The seeming status of M. nesbitte as a transitional species is reflected on behalf of the genera Peredo and his colleagues have chosen for their formal description of the fossils.

"The name is Maiabalaena, which combines" Maia ", meaning mother, and" whale ", meaning a kite," Peredo said. "It's called because of its position near the family tree base."

Peredo said that the name of the species, unsatisfactory, rewards Nesbitt for "his life's contribution to the paleontology of the northwest pacific and its mentorship and collegiality in the Burke museum."

Elizabeth Nesbitt
Elizabeth Nesbitt is the curator of paleontology of invertebrates and micropaleontology at the Burke Museum. (Washington Photo University)

Nesbitt studies fossils across Western North America, with a particular focus on marine fossils. The study also focuses on the microbiology of contemporary Puget Sound and how small beings known as foraminifera serve as key indicators of Puget Sound's health. (Spoiler warning: indicators do not look good.)

In addition to his research, Nesbitt has the role of the public as the curator of the bishop palaeontology and microthaleontology of the Burke Museum. The museum says it has gathered exhibits on the seismic history of the Pacific Northwest to the imaginative views of ancient fossils that they looked like in life.

Peredo was acquainted with Nesbitt's work partly because his research was using the extensive use of fossils from the state of Washington and Oregon – including, of course, the fossil now bearing its name.

In addition to Pereda and Pyongyang, Current Biology papers, titled "Tooth loss recognizing Baleena's origins in whales," include Christopher Marshall and Mark Uhen.


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