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A named fossil after curator Burke reports a whale of history about evolution – GeekWire


Carlos Mauricio Peredo
Carlos Mauricio Peredo, researcher at the National Museum of Natural History, shows a 33-year-old whale that has been distributed from a new line with the name Maiabalaena nesbittae. (Photo Smithsonian)

A whale that lived 33 million years ago when Oregon today was part of the seafront was named after a curator at the Burke Natural Nature and Culture Museum in Seattle.

And your typical ketacean is Elizabeth Nesbitt's whales: A fossil analysis, published in the 29th edition of Current Biology, suggests that an unbeatable Maiabalaena has bridged a gap between species of different whales and species that have different feed mechanism from the Baleen name.

"For the first time, we can now turn down the source of feed feeding, one of the main innovations in whale history," study co-writer Nicholas Pyenson, curator of marine fossil mammals and National Natural Museum. is an associated guardian at Burke Museum, in a news release.

M. nesbittae fossil was discovered in the 1970's and has since been studied widely. However, the rock matrix and material surrounding the fossil hid many of its features, formal frustrating classifications. Carlos Mauricio Peredo, a researcher at the National Museum of Natural History, then filled the fossil cleaner thoroughly and examined with the latest X-ray scanning technology.

The scans show that M. nesbittae teeth are flawed. That in itself is not a surprise: The whale, which probably measured 15 feet long in life, lived during a period when some whale species were making an evolutionary transition from using tooth to use a pallet instead of that.

Baleen is a rows of flexible, barren plates that use whale species such as a barrage and blue whales to filter a small predator of large water from seawater. The feeding technique makes it possible for Baleen whales to use tons of daily food without feeding or sewing.

What makes M. especially special is that its upper chin is thin and narrow, which seems to make it unsuitable to support the balloon structure.

"The Baleen whale has a large, large roof in its mouth, and it has also thickened to create attachment sites for the Baleen," said Peredo, who is the leading author of the Current Biology study. "Maiabalaena is not. We can tell you quite steady that these fossil species did not have tooth, and it's more likely than not to have a ballet, either."

That would support the assumption that whale species had developed to take advantage of a feeding strategy that did not require tooth or pallet.

Peredo and colleagues say that muscle attachments on M. nesbittae bones suggest that he has strong geeks and a removal tongue. They propose that the whale can suck a large amount of water in its mouth, taking small fish and squid in the process … without needing tooth. (The modern narrow, with only two intuitive teeth, uses a similar strategy.)

In this situation, toothpaste sets the stage for the appearance of feeding ballein structures millions millions of years later. The main factor behind the differences in feeding strategies, is similar, dramatic cooling of seabirds during the transition of the Eocene of the Oligocene, about 34 million from years ago.

The apparent status of M. nesbittae is reflected as a transitional species in the name of the genus Peredo and his colleagues chose for their formal description of the fossil.

"Maiabalaena is the name, which combines Maia, which means mother, and" palaine ", which means whale , "said Peredo. "He is named for his position near the bottom of the whale's whale family tree."

Peredo's name, nonsense, honors Nesbitt "for his contribution to the balcony of the North West Pacific and mentored his colleges at Burke Museum."

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

Nesbitt is studying fossils throughout western North America, with particular emphasis on marine fossils. Its research also focuses on today's Puget Sound microbiota, and how small creatures known as foraminifera are key indicators of Puget Sound's health. (Verbal warning: The indicators do not look good.)

As well as his research, Nesbitt plays a public outreach role as curator of invertebrate paleontology and microbiology of Burke Museum. The museum says it has produced exhibitions on topics ranging from the seismic history of the Pacific Ocean to imaginative representations of ancient fossils as they look into life.

Peredo is familiar with the work of Nesbitt partly because his own research has made extensive use of fossils from the state of Washington and Oregon – including, of course, the fossil that now closes its name.

As well as Peredo and Pyenson, the authors of the Current Biology paper, called "Loss of Depression Baleen Origin in Whales," include Christopher Marshall and Mark Uhen.

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