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News Article | December 8, 2016
Site: www.csmonitor.com

Tip of preserved tail section, showing carbon film at its surface exposure, and feathers arranged in keels down both sides of tail. It sounds like science fiction: a 99-million-year-old, feathery dinosaur tail encased in amber. But the specimen is real, and it is helping scientists envision how feathers evolved. "A lot of what we know about the evolution of feathers we've pieced together from two-dimensional data," Alan Turner, a paleontologist at Stony Brook University, tells The Christian Science Monitor. Most ancient feathers are preserved in compression fossils, formed in rock as preserved material is squished and flattened in the sediment. But feathers are not flat. So "having something three-dimensional like this is nice because the three-dimensional geometry is preserved." The amber specimen is described in a paper published Thursday in the journal Current Biology. A young, sparrow-sized dinosaur's tail likely brushed up against a tree sticky with resin some 99 million years ago. The middle section of the feathery tail was stuck. Over time, that resin hardened and turned into amber, perfectly preserving the dinosaur's tail and the feathers on it. Today, birds have feathers with a three-tiered branching structure. At the center of a long feather is the rachis, or central shaft. Smaller barbs stick out of the rachis and even smaller barbules emerge off of those barbs. The barbules interlock like velcro to hold each feather together, making it more useful for flight, among other things. But when a team of researchers scanned the chunk of amber containing the juvenile dinosaur's tail, they saw something different. "In this specimen, we're seeing barbs that are looking like they're branching off of each other" rather than a rachis, says study co-author Ryan McKellar, curator of invertebrate paleontology at the Royal Saskatchewan Museum, in an interview with the Monitor. And the barbules don't seem to zip together like they do in the flight feathers of modern birds. This would situate this dinosaur's feathers in a unique spot in feather development. In the 1990s Richard Prum, an evolutionary ornithologist at Yale University who was not involved in the new study, came up with a model of feather development by studying modern birds. He found that feathers start as a simple, hollow filament, called stage 1. Stage 2 is a tuft of several filaments, or barbs. Stage 3 is broken up into stage 3a and stage 3b, separate versions which later merge to become stage 3a+b. In stage 3a, a central rachis has formed with barbs coming off it in a series, but no barbules. Stage 3b sees barbules, but no rachis. Stage 3a+b sees feathers with a rachis, barbs, and barbules, but the barbules don't interlace. Stages 4 and 5 see the complexity of the barbules increasingly becoming like the feathers seen on birds today. "The morphology that the authors are presenting provides a glimpse into something that fits overall into the developmentally based models for feather evolution," says Stony Brook's Professor Turner, who was not involved in the research. It is "a new data point that will, over time, help us refine the model." Dr. McKellar and his colleagues assert that the amber-encased dinosaur feathers are a sort of hybrid between stage 3a and stage 3b, but not quite stage 3a+b because the central shaft has barbules coming off it more like a barb than a fully developed rachis. But Dr. Prum disagrees. "To me, this is absolutely stage 3a+b," he tells the Monitor. "Maybe the fact that it does have barbules on its rachis may indicate that its rachis identity has not proceeded to that strong stage, but I don't see it as separate." As such, Prum says the dinosaur's feathers are consistent with his model of feather evolution. That the dinosaur was a juvenile "introduces a little bit of uncertainty as to whether or not it might have had a different feather structure as an adult," McKellar admits. Birds today undergo molts as they grow, losing their baby feathers and replacing them with differently structured adult feathers. But, he says, "the feathers that we're seeing in this particular specimen match up better with adult contour feathers in modern birds than they do with the downy, first coat of feathers that most birds produce. So we think we're dealing with adult-like feathers." At one time, a specimen like this one would have been controversial, says Mark Norell, a paleontologist at the American Museum of Natural History who was not involved with this study. Scientists didn't always realize that birds are dinosaurs, so finding a dinosaur with feathers would have been a big surprise. But now it's an understood relationship among the vast majority of scientists that "birds are a kind of dinosaur and dinosaurs other than birds have feathers," Dr. Norell tells the Monitor. It's so unsurprising to find a dinosaur with feathers now, he says, "It's like predicting that a fossil mammal would have hair." Still, McKellar and his colleagues checked to be sure that this specimen was not actually an early bird. "Modern birds and their close relatives have something called a pygostyle, which is a fused series of tail vertebrae where they form a rod that supports the tail plumage," he explains. "And we're not seeing this in this particular specimen. We've got a flexible, whip-like tail instead of one of these big, sort of plowshare-shaped tails that we see in modern birds." The dinosaur's tail was probably used only for signaling or display of some sort, McKellar says, and wouldn't have been useful for flight or much else. The team's scans of the specimen revealed that the feathers on the topside of the tail were a chestnut brown color, while the underside of the tail was paler or perhaps white in color, somewhat like a white-tailed deer, he says. With just a handful of vertebrae and feathers preserved, the scientists know little about the dinosaur itself. But they were able to determine that the little beast was a coelurosaur theropod, a type of two-legged dinosaur. Dinosaur-era feathers have been found encased in amber before. Some were attached to entire bird wings, but most of these preserved feathers were not associated with the flesh or bones of an animal, so scientists couldn't determine much about the beast that wore them. "It's stunning to see these beautifully formed feathers from a representative that is clearly a coelurosaur," Prum says. One other tantalizing clue the team found in the amber was the chemical signature of ferrous iron in the thin carbon film where the animal's soft tissues would have been. That form of iron comes from blood proteins, like hemoglobin and ferritin. "It's thought, based on other specimens in the vertebrate fossil record, that traces of this particular form of iron might be linked to decay products from things like blood or tissue left behind," McKellar says. So this could allow researchers to study the soft tissues that almost never survive a hundred million years. Any Jurassic Park fan's interest might be piqued by the mention of dinosaur blood in amber, as the premise of the tale hinges on replicating the beasts' DNA from just that. In the fictional story, scientists clone dinosaurs using DNA extracted from blood that was preserved for millions of years in the digestive system of mosquitos trapped in amber. And, with bits of an actual dinosaur itself preserved in amber, this non-fictitious specimen seems to get closer to that possibility than even that science-fiction scenario. But don't expect live dinosaurs anytime soon, McKellar says. Research has shown that DNA cannot last in the fossil record for nearly long enough to survive from the age of the dinosaurs. With a half-life of about 521 years, it would take less than 7 million years for an organisms' DNA to be completely destroyed. The non-avian dinosaurs died about 65 million years ago, so their DNA is long gone. And, McKellar points out, with all kinds of debris and insects also stuck in the tree resin, the DNA sampled from an amber specimen may be from another organism, or even the tree itself. So, as exciting as it would be to clone 99-million-year-old organisms, a tree doesn't quite have the same thrill-factor as a dinosaur.


News Article | December 8, 2016
Site: www.csmonitor.com

Tip of preserved tail section, showing carbon film at its surface exposure, and feathers arranged in keels down both sides of tail. It sounds like science fiction: a 99-million-year-old, feathery dinosaur tail encased in amber. But the specimen is real, and it is helping scientists envision how feathers evolved. "A lot of what we know about the evolution of feathers we've pieced together from two-dimensional data," Alan Turner, a paleontologist at Stony Brook University, tells The Christian Science Monitor. Most ancient feathers are preserved in compression fossils, formed in rock as preserved material is squished and flattened in the sediment. But feathers are not flat. So "having something three-dimensional like this is nice because the three-dimensional geometry is preserved." The amber specimen is described in a paper published Thursday in the journal Current Biology. A young, sparrow-sized dinosaur's tail likely brushed up against a tree sticky with resin some 99 million years ago. The middle section of the feathery tail was stuck. Over time, that resin hardened and turned into amber, perfectly preserving the dinosaur's tail and the feathers on it. Today, birds have feathers with a three-tiered branching structure. At the center of a long feather is the rachis, or central shaft. Smaller barbs stick out of the rachis and even smaller barbules emerge off of those barbs. The barbules interlock like velcro to hold each feather together, making it more useful for flight, among other things. But when a team of researchers scanned the chunk of amber containing the juvenile dinosaur's tail, they saw something different. "In this specimen, we're seeing barbs that are looking like they're branching off of each other" rather than a rachis, says study co-author Ryan McKellar, curator of invertebrate paleontology at the Royal Saskatchewan Museum, in an interview with the Monitor. And the barbules don't seem to zip together like they do in the flight feathers of modern birds. This would situate this dinosaur's feathers in a unique spot in feather development. In the 1990s Richard Prum, an evolutionary ornithologist at Yale University who was not involved in the new study, came up with a model of feather development by studying modern birds. He found that feathers start as a simple, hollow filament, called stage 1. Stage 2 is a tuft of several filaments, or barbs. Stage 3 is broken up into stage 3a and stage 3b, separate versions which later merge to become stage 3a+b. In stage 3a, a central rachis has formed with barbs coming off it in a series, but no barbules. Stage 3b sees barbules, but no rachis. Stage 3a+b sees feathers with a rachis, barbs, and barbules, but the barbules don't interlace. Stages 4 and 5 see the complexity of the barbules increasingly becoming like the feathers seen on birds today. "The morphology that the authors are presenting provides a glimpse into something that fits overall into the developmentally based models for feather evolution," says Stony Brook's Professor Turner, who was not involved in the research. It is "a new data point that will, over time, help us refine the model." Dr. McKellar and his colleagues assert that the amber-encased dinosaur feathers are a sort of hybrid between stage 3a and stage 3b, but not quite stage 3a+b because the central shaft has barbules coming off it more like a barb than a fully developed rachis. But Dr. Prum disagrees. "To me, this is absolutely stage 3a+b," he tells the Monitor. "Maybe the fact that it does have barbules on its rachis may indicate that its rachis identity has not proceeded to that strong stage, but I don't see it as separate." As such, Prum says the dinosaur's feathers are consistent with his model of feather evolution. That the dinosaur was a juvenile "introduces a little bit of uncertainty as to whether or not it might have had a different feather structure as an adult," McKellar admits. Birds today undergo molts as they grow, losing their baby feathers and replacing them with differently structured adult feathers. But, he says, "the feathers that we're seeing in this particular specimen match up better with adult contour feathers in modern birds than they do with the downy, first coat of feathers that most birds produce. So we think we're dealing with adult-like feathers." At one time, a specimen like this one would have been controversial, says Mark Norell, a paleontologist at the American Museum of Natural History who was not involved with this study. Scientists didn't always realize that birds are dinosaurs, so finding a dinosaur with feathers would have been a big surprise. But now it's an understood relationship among the vast majority of scientists that "birds are a kind of dinosaur and dinosaurs other than birds have feathers," Dr. Norell tells the Monitor. It's so unsurprising to find a dinosaur with feathers now, he says, "It's like predicting that a fossil mammal would have hair." Still, McKellar and his colleagues checked to be sure that this specimen was not actually an early bird. "Modern birds and their close relatives have something called a pygostyle, which is a fused series of tail vertebrae where they form a rod that supports the tail plumage," he explains. "And we're not seeing this in this particular specimen. We've got a flexible, whip-like tail instead of one of these big, sort of plowshare-shaped tails that we see in modern birds." The dinosaur's tail was probably used only for signaling or display of some sort, McKellar says, and wouldn't have been useful for flight or much else. The team's scans of the specimen revealed that the feathers on the topside of the tail were a chestnut brown color, while the underside of the tail was paler or perhaps white in color, somewhat like a white-tailed deer, he says. With just a handful of vertebrae and feathers preserved, the scientists know little about the dinosaur itself. But they were able to determine that the little beast was a coelurosaur theropod, a type of two-legged dinosaur. Dinosaur-era feathers have been found encased in amber before. Some were attached to entire bird wings, but most of these preserved feathers were not associated with the flesh or bones of an animal, so scientists couldn't determine much about the beast that wore them. "It's stunning to see these beautifully formed feathers from a representative that is clearly a coelurosaur," Prum says. One other tantalizing clue the team found in the amber was the chemical signature of ferrous iron in the thin carbon film where the animal's soft tissues would have been. That form of iron comes from blood proteins, like hemoglobin and ferritin. "It's thought, based on other specimens in the vertebrate fossil record, that traces of this particular form of iron might be linked to decay products from things like blood or tissue left behind," McKellar says. So this could allow researchers to study the soft tissues that almost never survive a hundred million years. Any Jurassic Park fan's interest might be piqued by the mention of dinosaur blood in amber, as the premise of the tale hinges on replicating the beasts' DNA from just that. In the fictional story, scientists clone dinosaurs using DNA extracted from blood that was preserved for millions of years in the digestive system of mosquitos trapped in amber. And, with bits of an actual dinosaur itself preserved in amber, this non-fictitious specimen seems to get closer to that possibility than even that science-fiction scenario. But don't expect live dinosaurs anytime soon, McKellar says. Research has shown that DNA cannot last in the fossil record for nearly long enough to survive from the age of the dinosaurs. With a half-life of about 521 years, it would take less than 7 million years for an organisms' DNA to be completely destroyed. The non-avian dinosaurs died about 65 million years ago, so their DNA is long gone. And, McKellar points out, with all kinds of debris and insects also stuck in the tree resin, the DNA sampled from an amber specimen may be from another organism, or even the tree itself. So, as exciting as it would be to clone 99-million-year-old organisms, a tree doesn't quite have the same thrill-factor as a dinosaur.


News Article | December 8, 2016
Site: www.csmonitor.com

Tip of preserved tail section, showing carbon film at its surface exposure, and feathers arranged in keels down both sides of tail. It sounds like science fiction: a 99-million-year-old, feathery dinosaur tail encased in amber. But the specimen is real, and it is helping scientists envision how feathers evolved. "A lot of what we know about the evolution of feathers we've pieced together from two-dimensional data," Alan Turner, a paleontologist at Stony Brook University, tells The Christian Science Monitor. Most ancient feathers are preserved in compression fossils, formed in rock as preserved material is squished and flattened in the sediment. But feathers are not flat. So "having something three-dimensional like this is nice because the three-dimensional geometry is preserved." The amber specimen is described in a paper published Thursday in the journal Current Biology. A young, sparrow-sized dinosaur's tail likely brushed up against a tree sticky with resin some 99 million years ago. The middle section of the feathery tail was stuck. Over time, that resin hardened and turned into amber, perfectly preserving the dinosaur's tail and the feathers on it. Today, birds have feathers with a three-tiered branching structure. At the center of a long feather is the rachis, or central shaft. Smaller barbs stick out of the rachis and even smaller barbules emerge off of those barbs. The barbules interlock like velcro to hold each feather together, making it more useful for flight, among other things. But when a team of researchers scanned the chunk of amber containing the juvenile dinosaur's tail, they saw something different. "In this specimen, we're seeing barbs that are looking like they're branching off of each other" rather than a rachis, says study co-author Ryan McKellar, curator of invertebrate paleontology at the Royal Saskatchewan Museum, in an interview with the Monitor. And the barbules don't seem to zip together like they do in the flight feathers of modern birds. This would situate this dinosaur's feathers in a unique spot in feather development. In the 1990s Richard Prum, an evolutionary ornithologist at Yale University who was not involved in the new study, came up with a model of feather development by studying modern birds. He found that feathers start as a simple, hollow filament, called stage 1. Stage 2 is a tuft of several filaments, or barbs. Stage 3 is broken up into stage 3a and stage 3b, separate versions which later merge to become stage 3a+b. In stage 3a, a central rachis has formed with barbs coming off it in a series, but no barbules. Stage 3b sees barbules, but no rachis. Stage 3a+b sees feathers with a rachis, barbs, and barbules, but the barbules don't interlace. Stages 4 and 5 see the complexity of the barbules increasingly becoming like the feathers seen on birds today. "The morphology that the authors are presenting provides a glimpse into something that fits overall into the developmentally based models for feather evolution," says Stony Brook's Professor Turner, who was not involved in the research. It is "a new data point that will, over time, help us refine the model." Dr. McKellar and his colleagues assert that the amber-encased dinosaur feathers are a sort of hybrid between stage 3a and stage 3b, but not quite stage 3a+b because the central shaft has barbules coming off it more like a barb than a fully developed rachis. But Dr. Prum disagrees. "To me, this is absolutely stage 3a+b," he tells the Monitor. "Maybe the fact that it does have barbules on its rachis may indicate that its rachis identity has not proceeded to that strong stage, but I don't see it as separate." As such, Prum says the dinosaur's feathers are consistent with his model of feather evolution. That the dinosaur was a juvenile "introduces a little bit of uncertainty as to whether or not it might have had a different feather structure as an adult," McKellar admits. Birds today undergo molts as they grow, losing their baby feathers and replacing them with differently structured adult feathers. But, he says, "the feathers that we're seeing in this particular specimen match up better with adult contour feathers in modern birds than they do with the downy, first coat of feathers that most birds produce. So we think we're dealing with adult-like feathers." At one time, a specimen like this one would have been controversial, says Mark Norell, a paleontologist at the American Museum of Natural History who was not involved with this study. Scientists didn't always realize that birds are dinosaurs, so finding a dinosaur with feathers would have been a big surprise. But now it's an understood relationship among the vast majority of scientists that "birds are a kind of dinosaur and dinosaurs other than birds have feathers," Dr. Norell tells the Monitor. It's so unsurprising to find a dinosaur with feathers now, he says, "It's like predicting that a fossil mammal would have hair." Still, McKellar and his colleagues checked to be sure that this specimen was not actually an early bird. "Modern birds and their close relatives have something called a pygostyle, which is a fused series of tail vertebrae where they form a rod that supports the tail plumage," he explains. "And we're not seeing this in this particular specimen. We've got a flexible, whip-like tail instead of one of these big, sort of plowshare-shaped tails that we see in modern birds." The dinosaur's tail was probably used only for signaling or display of some sort, McKellar says, and wouldn't have been useful for flight or much else. The team's scans of the specimen revealed that the feathers on the topside of the tail were a chestnut brown color, while the underside of the tail was paler or perhaps white in color, somewhat like a white-tailed deer, he says. With just a handful of vertebrae and feathers preserved, the scientists know little about the dinosaur itself. But they were able to determine that the little beast was a coelurosaur theropod, a type of two-legged dinosaur. Dinosaur-era feathers have been found encased in amber before. Some were attached to entire bird wings, but most of these preserved feathers were not associated with the flesh or bones of an animal, so scientists couldn't determine much about the beast that wore them. "It's stunning to see these beautifully formed feathers from a representative that is clearly a coelurosaur," Prum says. One other tantalizing clue the team found in the amber was the chemical signature of ferrous iron in the thin carbon film where the animal's soft tissues would have been. That form of iron comes from blood proteins, like hemoglobin and ferritin. "It's thought, based on other specimens in the vertebrate fossil record, that traces of this particular form of iron might be linked to decay products from things like blood or tissue left behind," McKellar says. So this could allow researchers to study the soft tissues that almost never survive a hundred million years. Any Jurassic Park fan's interest might be piqued by the mention of dinosaur blood in amber, as the premise of the tale hinges on replicating the beasts' DNA from just that. In the fictional story, scientists clone dinosaurs using DNA extracted from blood that was preserved for millions of years in the digestive system of mosquitos trapped in amber. And, with bits of an actual dinosaur itself preserved in amber, this non-fictitious specimen seems to get closer to that possibility than even that science-fiction scenario. But don't expect live dinosaurs anytime soon, McKellar says. Research has shown that DNA cannot last in the fossil record for nearly long enough to survive from the age of the dinosaurs. With a half-life of about 521 years, it would take less than 7 million years for an organisms' DNA to be completely destroyed. The non-avian dinosaurs died about 65 million years ago, so their DNA is long gone. And, McKellar points out, with all kinds of debris and insects also stuck in the tree resin, the DNA sampled from an amber specimen may be from another organism, or even the tree itself. So, as exciting as it would be to clone 99-million-year-old organisms, a tree doesn't quite have the same thrill-factor as a dinosaur.


News Article | December 8, 2016
Site: www.csmonitor.com

Tip of preserved tail section, showing carbon film at its surface exposure, and feathers arranged in keels down both sides of tail. It sounds like science fiction: a 99-million-year-old, feathery dinosaur tail encased in amber. But the specimen is real, and it is helping scientists envision how feathers evolved. "A lot of what we know about the evolution of feathers we've pieced together from two-dimensional data," Alan Turner, a paleontologist at Stony Brook University, tells The Christian Science Monitor. Most ancient feathers are preserved in compression fossils, formed in rock as preserved material is squished and flattened in the sediment. But feathers are not flat. So "having something three-dimensional like this is nice because the three-dimensional geometry is preserved." The amber specimen is described in a paper published Thursday in the journal Current Biology. A young, sparrow-sized dinosaur's tail likely brushed up against a tree sticky with resin some 99 million years ago. The middle section of the feathery tail was stuck. Over time, that resin hardened and turned into amber, perfectly preserving the dinosaur's tail and the feathers on it. Today, birds have feathers with a three-tiered branching structure. At the center of a long feather is the rachis, or central shaft. Smaller barbs stick out of the rachis and even smaller barbules emerge off of those barbs. The barbules interlock like velcro to hold each feather together, making it more useful for flight, among other things. But when a team of researchers scanned the chunk of amber containing the juvenile dinosaur's tail, they saw something different. "In this specimen, we're seeing barbs that are looking like they're branching off of each other" rather than a rachis, says study co-author Ryan McKellar, curator of invertebrate paleontology at the Royal Saskatchewan Museum, in an interview with the Monitor. And the barbules don't seem to zip together like they do in the flight feathers of modern birds. This would situate this dinosaur's feathers in a unique spot in feather development. In the 1990s Richard Prum, an evolutionary ornithologist at Yale University who was not involved in the new study, came up with a model of feather development by studying modern birds. He found that feathers start as a simple, hollow filament, called stage 1. Stage 2 is a tuft of several filaments, or barbs. Stage 3 is broken up into stage 3a and stage 3b, separate versions which later merge to become stage 3a+b. In stage 3a, a central rachis has formed with barbs coming off it in a series, but no barbules. Stage 3b sees barbules, but no rachis. Stage 3a+b sees feathers with a rachis, barbs, and barbules, but the barbules don't interlace. Stages 4 and 5 see the complexity of the barbules increasingly becoming like the feathers seen on birds today. "The morphology that the authors are presenting provides a glimpse into something that fits overall into the developmentally based models for feather evolution," says Stony Brook's Professor Turner, who was not involved in the research. It is "a new data point that will, over time, help us refine the model." Dr. McKellar and his colleagues assert that the amber-encased dinosaur feathers are a sort of hybrid between stage 3a and stage 3b, but not quite stage 3a+b because the central shaft has barbules coming off it more like a barb than a fully developed rachis. But Dr. Prum disagrees. "To me, this is absolutely stage 3a+b," he tells the Monitor. "Maybe the fact that it does have barbules on its rachis may indicate that its rachis identity has not proceeded to that strong stage, but I don't see it as separate." As such, Prum says the dinosaur's feathers are consistent with his model of feather evolution. That the dinosaur was a juvenile "introduces a little bit of uncertainty as to whether or not it might have had a different feather structure as an adult," McKellar admits. Birds today undergo molts as they grow, losing their baby feathers and replacing them with differently structured adult feathers. But, he says, "the feathers that we're seeing in this particular specimen match up better with adult contour feathers in modern birds than they do with the downy, first coat of feathers that most birds produce. So we think we're dealing with adult-like feathers." At one time, a specimen like this one would have been controversial, says Mark Norell, a paleontologist at the American Museum of Natural History who was not involved with this study. Scientists didn't always realize that birds are dinosaurs, so finding a dinosaur with feathers would have been a big surprise. But now it's an understood relationship among the vast majority of scientists that "birds are a kind of dinosaur and dinosaurs other than birds have feathers," Dr. Norell tells the Monitor. It's so unsurprising to find a dinosaur with feathers now, he says, "It's like predicting that a fossil mammal would have hair." Still, McKellar and his colleagues checked to be sure that this specimen was not actually an early bird. "Modern birds and their close relatives have something called a pygostyle, which is a fused series of tail vertebrae where they form a rod that supports the tail plumage," he explains. "And we're not seeing this in this particular specimen. We've got a flexible, whip-like tail instead of one of these big, sort of plowshare-shaped tails that we see in modern birds." The dinosaur's tail was probably used only for signaling or display of some sort, McKellar says, and wouldn't have been useful for flight or much else. The team's scans of the specimen revealed that the feathers on the topside of the tail were a chestnut brown color, while the underside of the tail was paler or perhaps white in color, somewhat like a white-tailed deer, he says. With just a handful of vertebrae and feathers preserved, the scientists know little about the dinosaur itself. But they were able to determine that the little beast was a coelurosaur theropod, a type of two-legged dinosaur. Dinosaur-era feathers have been found encased in amber before. Some were attached to entire bird wings, but most of these preserved feathers were not associated with the flesh or bones of an animal, so scientists couldn't determine much about the beast that wore them. "It's stunning to see these beautifully formed feathers from a representative that is clearly a coelurosaur," Prum says. One other tantalizing clue the team found in the amber was the chemical signature of ferrous iron in the thin carbon film where the animal's soft tissues would have been. That form of iron comes from blood proteins, like hemoglobin and ferritin. "It's thought, based on other specimens in the vertebrate fossil record, that traces of this particular form of iron might be linked to decay products from things like blood or tissue left behind," McKellar says. So this could allow researchers to study the soft tissues that almost never survive a hundred million years. Any Jurassic Park fan's interest might be piqued by the mention of dinosaur blood in amber, as the premise of the tale hinges on replicating the beasts' DNA from just that. In the fictional story, scientists clone dinosaurs using DNA extracted from blood that was preserved for millions of years in the digestive system of mosquitos trapped in amber. And, with bits of an actual dinosaur itself preserved in amber, this non-fictitious specimen seems to get closer to that possibility than even that science-fiction scenario. But don't expect live dinosaurs anytime soon, McKellar says. Research has shown that DNA cannot last in the fossil record for nearly long enough to survive from the age of the dinosaurs. With a half-life of about 521 years, it would take less than 7 million years for an organisms' DNA to be completely destroyed. The non-avian dinosaurs died about 65 million years ago, so their DNA is long gone. And, McKellar points out, with all kinds of debris and insects also stuck in the tree resin, the DNA sampled from an amber specimen may be from another organism, or even the tree itself. So, as exciting as it would be to clone 99-million-year-old organisms, a tree doesn't quite have the same thrill-factor as a dinosaur.


News Article | December 8, 2016
Site: www.rdmag.com

Researchers have discovered a dinosaur tail complete with its feathers trapped in a piece of amber. The finding reported in Current Biology on December 8 helps to fill in details of the dinosaurs' feather structure and evolution, which can't be determined from fossil evidence. While the feathers aren't the first to be found in amber, earlier specimens have been difficult to definitively link to their source animal, the researchers say. "The new material preserves a tail consisting of eight vertebrae from a juvenile; these are surrounded by feathers that are preserved in 3D and with microscopic detail," says Ryan McKellar of the Royal Saskatchewan Museum in Canada. "We can be sure of the source because the vertebrae are not fused into a rod or pygostyle as in modern birds and their closest relatives. Instead, the tail is long and flexible, with keels of feathers running down each side." In other words, the feathers definitely are those of a dinosaur not a prehistoric bird. The study's first author Lida Xing from the China University of Geosciences (Beijing) discovered the remarkable specimen at an amber market in Myitkyina, Myanmar in 2015. The amber piece was originally seen as some kind of plant inclusion and destined to become a curiosity or piece of jewelry, but Xing recognized its potential scientific importance and suggested that the Dexu Institute of Palaeontology buy the specimen. The researchers say that the specimen represents the feathered tail of a non-avialan theropod preserved in mid-Cretaceous amber about 99 million years ago. While it was initially difficult to make out the details of the amber inclusion, Xing and his colleagues relied on CT scanning and microscopic observations to get a closer look. The feathers suggest that the tail had a chestnut-brown upper surface and a pale or white underside. The specimen also offers insight into feather evolution. The feathers lack a well-developed central shaft or rachis. Their structure suggests that the two finest tiers of branching in modern feathers, known as barbs and barbules, arose before a rachis formed. The researchers also examined the chemistry of the tail inclusion where it was exposed at the surface of the amber. The analysis shows that the soft tissue layer around the bones retained traces of ferrous iron, a relic left over from hemoglobin that was also trapped in the sample. The findings show the value of amber as a supplement to the fossil record. "Amber pieces preserve tiny snapshots of ancient ecosystems, but they record microscopic details, three-dimensional arrangements, and labile tissues that are difficult to study in other settings," McKellar says. "This is a new source of information that is worth researching with intensity and protecting as a fossil resource." The researchers say they are now "eager to see how additional finds from this region will reshape our understanding of plumage and soft tissues in dinosaurs and other vertebrates."


News Article | December 9, 2016
Site: www.gizmag.com

There's only so much palaeontologists can learn about prehistoric animals from fossilized bones, so on rare occasions when ancient soft tissues turn up, it's worth taking note. Recent discoveries of preserved brains, cartilage and skin have provided some unique insights into how dinosaurs may have looked and sounded, and now a section of a dinosaur's tail, complete with feathers, has been found trapped in a piece of amber. The study's first author, Lida Xing, uncovered the relic, but not at a dig site – it turned up at an amber market in Myanmar in 2015. Originally thought to contain some kind of plant, Xing saved the important find from becoming a tacky piece of jewellery, and the Dexu Institute of Palaeontology snapped it up for study. Feathers have turned up in amber before, but this discovery is the first to be found connected to bone and other tissue, allowing the scientists to narrow the owner's species down to a dinosaur from the Coelurosaur family, a subgroup of therapods that includes modern-day birds as well as the mighty Tyrannosaurus Rex. "The new material preserves a tail consisting of eight vertebrae from a juvenile; these are surrounded by feathers that are preserved in 3D and with microscopic detail," says Ryan McKellar, of the Royal Saskatchewan Museum in Canada. "We can be sure of the source because the vertebrae are not fused into a rod or pygostyle as in modern birds and their closest relatives. Instead, the tail is long and flexible, with keels of feathers running down each side." The specimen hails from the mid-Cretaceous period around 99 million years ago, and judging by the color of the feathers, the animal (or at least its tail) would've been chestnut-brown on top, with a pale underside. Compared to those of modern animals, the feathers themselves are oddly-shaped with no well-defined shaft down the middle, hinting that in evolutionary terms, the finer branches at the tips of feathers, known as barbs and barbules, developed earlier than the central shaft. CT scans and microscopic observations helped the researchers peer through the murky amber, and by performing a chemical analysis of the soft tissue where the tail meets the surface of the material, the scientists found traces of ferrous iron, a compound from the animal's red blood cells. These kinds of discoveries can't be found in the fossil record alone. "Amber pieces preserve tiny snapshots of ancient ecosystems, but they record microscopic details, three-dimensional arrangements, and labile tissues that are difficult to study in other settings," says McKellar. "This is a new source of information that is worth researching with intensity and protecting as a fossil resource." The scientists are on the hunt for other potential finds in the region, in the hopes of furthering the study of dinosaur plumage and tissue.


News Article | December 9, 2016
Site: www.chromatographytechniques.com

Researchers have discovered a dinosaur tail complete with its feathers trapped in a piece of amber. The finding reported in Current Biology on December 8 helps to fill in details of the dinosaurs' feather structure and evolution, which can't be determined from fossil evidence. While the feathers aren't the first to be found in amber, earlier specimens have been difficult to definitively link to their source animal, the researchers say. "The new material preserves a tail consisting of eight vertebrae from a juvenile; these are surrounded by feathers that are preserved in 3D and with microscopic detail," says Ryan McKellar of the Royal Saskatchewan Museum in Canada. "We can be sure of the source because the vertebrae are not fused into a rod or pygostyle as in modern birds and their closest relatives. Instead, the tail is long and flexible, with keels of feathers running down each side." In other words, the feathers definitely are those of a dinosaur not a prehistoric bird. The study's first author Lida Xing from the China University of Geosciences (Beijing) discovered the remarkable specimen at an amber market in Myitkyina, Myanmar in 2015. The amber piece was originally seen as some kind of plant inclusion and destined to become a curiosity or piece of jewelry, but Xing recognized its potential scientific importance and suggested that the Dexu Institute of Palaeontology buy the specimen. The researchers say that the specimen represents the feathered tail of a non-avialan theropod preserved in mid-Cretaceous amber about 99 million years ago. While it was initially difficult to make out the details of the amber inclusion, Xing and his colleagues relied on CT scanning and microscopic observations to get a closer look. The feathers suggest that the tail had a chestnut-brown upper surface and a pale or white underside. The specimen also offers insight into feather evolution. The feathers lack a well-developed central shaft or rachis. Their structure suggests that the two finest tiers of branching in modern feathers, known as barbs and barbules, arose before a rachis formed. The researchers also examined the chemistry of the tail inclusion where it was exposed at the surface of the amber. The analysis shows that the soft tissue layer around the bones retained traces of ferrous iron, a relic left over from hemoglobin that was also trapped in the sample. The findings show the value of amber as a supplement to the fossil record. "Amber pieces preserve tiny snapshots of ancient ecosystems, but they record microscopic details, three-dimensional arrangements, and labile tissues that are difficult to study in other settings," McKellar says. "This is a new source of information that is worth researching with intensity and protecting as a fossil resource." The researchers say they are now "eager to see how additional finds from this region will reshape our understanding of plumage and soft tissues in dinosaurs and other vertebrates."


News Article | December 8, 2016
Site: motherboard.vice.com

For Lida Xing, a paleontologist based at the China University of Geosciences, scientific progress occasionally calls for some light espionage. This kind of situation arose last year, after he made an astonishing discovery at an amber market in Myitkyina, Myanmar. Suspended within a snowglobe-sized chunk of fossilized tree resin, Xing recognized the partial remains of an exquisitely preserved feathered tail belonging to a small juvenile coelurosaur, a type of bird-like dinosaur. The fossil dates 99 million years back to the middle Cretaceous period, when temperatures were warm, sea levels were high, and dinosaurs walked among the earliest flowering plants. Its discovery at the market was a stroke of "great luck," Xing told me over email. "I often visit amber markets," he said. "But this is the only dinosaur amber I've ever seen." So, where does the paleontological reconnaissance come in? Burmese amber markets happen to be fed by amber mines in Hukawng Valley, located in the Kachin State of northern Myanmar. This region is currently under the control of the insurgent Kachin Independence Army, which has a long history of conflict with the Burmese government. "Resellers buy scraps from amber miners and sell them on the markets," Xing explained. "The mines are extremely dangerous, so foreigners can hardly get there." Xing decided to go undercover. "I disguised myself as a Burmese man with a face painted with Thanaka," he told me. (Thanaka is a popular cosmetic paste in Myanmar, yellowish-white in color, made from finely ground tree bark.) Stealthily camouflaged and armed with a fake ID, Xing snuck into the region. He met the prospector responsible for excavating the dinosaur tail, who guided Xing through the mines and showed him new geological samples. "We are very lucky," he said of the escapade. As for the dinosaur tail itself, Xing persuaded the Dexu Institute of Palaeontology in Chaozhou to purchase it, and has since headed up an international team of researchers to analyse the fossil with computerized tomography (CT) scanning techniques. The results, published Thursday in Current Biology, shed light on the evolution of feathers and reveal intimate details about this particular coelurosaur, including its coloration pattern, skeletal features, and even the hemoglobin molecules that ran through its blood, which left traces of iron oxide within the tail. Xing and his co-authors, including paleontologists Ryan McKellar of the Royal Saskatchewan Museum and Philip J. Currie of the University of Alberta, were able to identify the animal as coelurosaur by its flexible vertebral structure, which distinguishes it from the fused rod-like spines of avian dinosaurs that would have sported similar feathered plumages. The feather coloration pattern suggests that the young dinosaur had chestnut-brown dorsal feathers, while its underbelly was pale. Xing told me that the brown feathers may have acted as "protective coloration," helping the coelurosaur blend into the woodland environments in which it is presumed to have lived. Small coelurosaurs would likely have scuttled on the ground hunting insects in tropical forests, likely populated by trees similar to those of Kauri trees extant in New Zealand. That said, there is still a lot to learn about Myanmar's rich paleontological history. READ MORE: A Tour of the Ancient Life Still Trapped in Amber "The environment of the middle Cretaceous from northern Myanmar does not appear to be formally studied," Xing said. This gap in paleontological knowledge is caused both by the remote location of amber mines and fossil beds in the region, as well as the longstanding social and political unrest that makes much of Myanmar's north off-limits to outsiders. The fact that this gorgeous snapshot of the Cretaceous world wound up in a Burmese amber market seems like a great incentive for more paleontologists to scout out local vendors. Indeed, Xing and McKellar previously teamed up on a June 2016 study about an amber specimen containing spectacular Cretaceous bird wings, which was also sourced from these markets. Hopefully, these recent discoveries will spark efforts to collect more of these astonishing amber-encased time capsules, even if it requires top secret dinosaurian espionage. These fossils may not bring dinosaurs back to life, as in Jurassic Park, but they still offer valuable and vivid tableaus of long-dead ecosystems. Get six of our favorite Motherboard stories every day by signing up for our newsletter.


News Article | December 22, 2016
Site: news.yahoo.com

A chunk of amber - fossilized resin - spotted by a Chinese scientist in a market in Myitkyina, Myanmar, last year shows the tip of a preserved dinosaur tail section in this image released by the Royal Saskatchewan Museum in Canada on December 8, 2016. Courtesy R.C. McKellar/Royal Saskatchewan Museum (RSM)/Handout via REUTERS WASHINGTON (Reuters) - A modest little dinosaur that scampered across northwestern China 160 million years ago boasted a unique trait not seen in any other dinosaur or other prehistoric creature yet unearthed: it was born with teeth but became toothless by adulthood. Scientists on Thursday said fossils of 19 individuals of a dinosaur called Limusaurus, ranging in age from under a year to 10 years, showed that juveniles had small, sharp teeth but adults developed a toothless beak. This cluster of dinosaurs, found in Xinjiang Province, apparently became hopelessly trapped in a mud pit and died. Only rarely have scientists found fossils of a dinosaur species ranging from babies to adults, a sequence revealing various anatomical changes that unfold as an animal matures. Limusaurus was a lightly built two-legged dinosaur with short arms and long, slender legs. It may have had down-like feathers covering at least part of its body. The largest ones were about 6 feet long (under 2 meters). "It probably looked something like an emu with a long tail," said George Washington University paleontologist Joey Stiegler, one of the researchers in the study published in the journal Current Biology. Such tooth loss is called ontogenetic edentulism. Some animals alive today have it, including the egg-laying Australian mammal the platypus. The adult Limusaurus individuals also were found with stones called gastroliths that some plant-eating dinosaurs swallowed to grind up plant material in the stomach. The babies lacked these. The tooth loss and gastroliths indicate Limusaurus underwent a dramatic dietary change from birth to adulthood, starting life perhaps eating insects and small vertebrates before later turning to plants. Limusaurus is a member of the theropod dinosaur group within which birds evolved. George Washington University paleontologist James Clark said the findings suggest "species close to the origin of birds may have gone through a similar development, and tooth loss may have been gradual during the evolutionary origin of birds." "This is important in showing that growth and development in dinosaurs was more complex than previously suspected, and it provides a model for a stage that birds may have gone through in evolving their beak," Clark added. Birds, first appearing about 150 million years ago, evolved from small feathered dinosaurs. The earliest ones had teeth. Over tens of millions of years, many evolved toothless beaks like those in today's birds. The last birds with teeth died with the dinosaurs about 66 million years ago.


News Article | December 9, 2016
Site: news.yahoo.com

WASHINGTON (Reuters) - Some 99 million years ago, a juvenile dinosaur got its feathery tail stuck in tree resin, a death trap for the small creature. But its misfortune is now giving scientists unique insight into feathered dinosaurs that prospered during the Cretaceous Period. Researchers said on Thursday a chunk of amber - fossilized resin - spotted by a Chinese scientist in a market in Myitkyina, Myanmar, last year contained 1.4 inches (36 mm) of the tail of the dinosaur, complete with bones, flesh, skin and feathers. The dinosaur itself was no more than 6 inches (15 cm) long, about the size of a sparrow. "This is the first of its kind," said paleontologist Ryan McKellar of the Royal Saskatchewan Museum in Canada, one of the researchers involved in the study published in the journal Current Biology. "I'm blown away." The scientists suspect the tail belonged to a type of two-legged, bird-like dinosaur called a maniraptoran, one of several groups of dinosaurs that possessed feathers. Birds, which first appeared about 150 million years ago during the Jurassic Period, evolved from small, feathered dinosaurs. The researchers used sophisticated scanning and microscopic observations to study the tail. They determined it boasted a chestnut-brown upper surface, with a pale or white underside, a pattern known as countershading. "We're seeing feathers still attached to the tail, and we can see how they attach, the shapes that they have down to the micrometer scale, and things like pigment patterns within the feathers," McKellar said. The tail consisted of eight vertebrae, soft tissue and feathers exquisitely preserved in three dimensions. McKellar said getting its tail stuck in resin "would have been a game-ender for that particular animal. They don't drop their tails like some lizards." The tail's anatomy enabled the scientists to rule out that it belonged to a bird because it was long and flexible and lacked a pygostyle, fused vertebrae that in birds support the tail feathers. The discovery also sheds light on the evolution of feathers. The ones trapped in the amber were more primitive than those of birds, lacking much of the central shaft seen in bird feathers. Amber has long been a boon to paleontologists. Numerous creatures have been found entombed in amber, including insects, lizards, amphibians, mammals and birds, as well as plants including flowers.

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