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More evidence of bird evolution.
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More evidence of bird evolution.
Glendower: I can call spirits from the vasty deep.
Hotspur: Why, so can I, or so can any man;
But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:
go with the flow the river knows . . .
Frank
I do not know, therefore everything is in pencil. -
Oldest known bird fossil discovered 67 million years old,
Glendower: I can call spirits from the vasty deep.
Hotspur: Why, so can I, or so can any man;
But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:
go with the flow the river knows . . .
Frank
I do not know, therefore everything is in pencil.
-
A new early important transitional species between raptors and birds.
One point that this reference did not make clear, which is an important factor that makes this discovery very important is that the Ravenavis family this species is an older primitive missing link that is more closely related to Avialae the family that birds more directly descended from. Both Unenlagia and the Ravenavis families of Therapod dinosaurs and had feathered bied like dinosaurs. There are not many fossils of species from Ravenavis family. In fact I believe the only other species in this family is found in Madagascar.Last edited by shunyadragon; 06-08-2020, 10:35 AM.Glendower: I can call spirits from the vasty deep.
Hotspur: Why, so can I, or so can any man;
But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:
go with the flow the river knows . . .
Frank
I do not know, therefore everything is in pencil.
Comment
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More recent analysis of an older unique discovery of a bird-like dinosaur reveals evidence of a more continuum of evolution from dinosaurs to birds.
One-of-a-Kind Dinosaur Specimen Discovered in China Offers View Into Dinosaur-Bird Evolution
TOPICS:BirdsDinosaursEvolutionPaleontologyPopularS an Diego Natural History Museum
By SAN DIEGO NATURAL HISTORY MUSEUM JANUARY 19, 2020
San Diego Natural History Museum paleontologist describes a dinosaur that is new to science, shows dinosaurs grew up differently from birds.
A new species of feathered dinosaur has been discovered in China, and described by American and Chinese authors in the journal, The Anatomical Record.
The one-of-a-kind specimen offers a window into what the earth was like 120 million years ago. The fossil preserves feathers and bones that provide new information about how dinosaurs grew and how they differed from birds.
“The new dinosaur fits in with an incredible radiation of feathered, winged animals that are closely related to the origin of birds,” said Dr. Ashley Poust, who analyzed the specimen while he was a student at Montana State University and during his time as a Ph.D. student at University of California, Berkeley. Poust is now postdoctoral researcher at the San Diego Natural History Museum.
Scientists named the dinosaur Wulong bohaiensis. Wulong is Chinese for “the dancing dragon” and references the position of the beautifully articulated specimen.
About the Discovery
The specimen was found more than a decade ago by a farmer in China, in the fossil-rich Jehol Province, and since then has been housed in the collection of The Dalian Natural History Museum in Liaoning, a northeastern Chinese province bordering North Korea and the Yellow Sea. The skeletal bones were analyzed by Poust alongside his advisor, Dr. David Varricchio, from Montana State University while Poust was a student there.
Larger than a common crow and smaller than a raven, but with a long, bony tail which would have doubled its length, Wulong bohaiensis had a narrow face filled with sharp teeth. Its bones were thin and small, and the animal was covered with feathers, including a wing-like array on both its arms and legs and two long plumes at the end of its tail.
This animal is one of the earliest relatives of Velociraptor, the famous dromaeosaurid theropod dinosaur that lived approximately 75 million years ago. Wulong’s closest well-known relative would have been Microraptor, a genus of small, four-winged paravian dinosaurs.
The discovery is significant not only because it describes a dinosaur that is new to science, but also because it shows connection between birds and dinosaurs.
“The specimen has feathers on its limbs and tail that we associate with adult birds, but it had other features that made us think it was a juvenile,” said Poust. To understand this contradiction, the scientists cut up several bones of the new dinosaur to examine under a microscope. This technique, called bone histology, is becoming a regular part of the paleontology toolbox, but it’s still sometimes difficult to convince museums to let a researcher remove part of a nice skeleton. “Thankfully, our coauthors at the Dalian Natural History Museum were really forward thinking and allowed us to apply these techniques, not only to Wulong, but also to another dinosaur, a close relative that looked more adult called Sinornithosaurus.”
The bones showed that the new dinosaur was a juvenile. This means that at least some dinosaurs were getting very mature looking feathers well before they were done growing. Birds grow up very fast and often don’t get their adult plumage until well after they are full sized. Showy feathers, especially those used for mating, are particularly delayed. And yet here was an immature dinosaur with two long feathers extending beyond the tip of the tail.
“Either the young dinosaurs needed these tail feathers for some function we don’t know about, or they were growing their feathers really differently from most living birds,” explained Poust.
An additional surprise came from the second dinosaur the scientists sampled; Sinornithosaurus wasn’t done growing either. The bone tissue was that of an actively growing animal and it lacked an External Fundamental System: a structure on the outside of the bone that vertebrates form when they’re full size. “Here was an animal that was large and had adult looking bones: we thought it was going to be mature, but histology proved that idea wrong. It was older than Wulong, but seems to have been still growing. Researchers need to be really careful about determining whether a specimen is adult or not. Until we learn a lot more, histology is really the most dependable way.”
“We’re talking about animals that lived twice as long ago as T. rex, so it’s pretty amazing how well preserved they are. It’s really very exciting to see inside these animals for the first time.”
Reference: “A new microraptorine theropod from the Jehol Biota and growth in early dromaeosaurids” by Ashley W. Poust, Chunling Gao, David J. Varricchio, Jianlin Wu and Fengjiao Zhang, 15 January 2020, The Anatomical Record.
DOI: 10.1002/ar.24343 [/cite]Glendower: I can call spirits from the vasty deep.
Hotspur: Why, so can I, or so can any man;
But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:
go with the flow the river knows . . .
Frank
I do not know, therefore everything is in pencil.
Comment
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The tinniest dinosaur sesxribed in post #1: Source: https://www.scientificamerican.com/a...ound-in-amber/ is not likely dinosaur nor bird, but a lizard. Later comparitive anatomy research made the determination.
Source : https://www.nbcnews.com/science/scie...osaur-n1235659Glendower: I can call spirits from the vasty deep.
Hotspur: Why, so can I, or so can any man;
But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:
go with the flow the river knows . . .
Frank
I do not know, therefore everything is in pencil.
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