NYDailyNews.com: Dinosaurs! An awe-inspiring look at the life of these gigantic creatures
The newest — and probably largest — New Yorker goes by the name of Mamenchisaurus,
and just as for many New Yorkers, moving to her new digs has been a battle.
Mamenchisaurus is the tractor-trailer-size star of "The World's Largest Dinosaurs," an exhibit opening at the American Museum of Natural History on Saturday.
The colossal creature, a female, took 100 people two years to create. She's an awesome example of long-necked, long-tailed sauropods.
But there's a reason for the show-stopping size.
"It's made in the way that those old invisible human models used to be," explains the exhibit's curator, Mark Norell. "One side of it appears as the way the animal would have looked in life. But on the other side, the skin is pulled back to reveal muscles, bones, organs and the mechanics of the inside of the animal and how it worked.
"We actually animate a lot of the internal organs by projecting on the outside of it, so that we can talk about the different layers of the anatomy and see things like the lungs work and heart beat and food passing through the animal," he adds. "So it's a very dynamic, lively sort of thing."
The hulking herbivore — that's right, sauropods got that big eating plants alone — is made out of polyurethane, synthetic material commonly used as a packing foam.
"We constructed it by sculpting a small version of it about 6 feet long," Norell says. "Then that was laser-scanned, and molds for the full-size model were then prototyped off of that."
The Mamenchisaurus stands 11 feet tall and stretches 60 feet long, but she isn't even half as big as some sauropods grew to be. That would be 150 feet long.
The latest technology is used to explain almost everything imaginable about the extinct creature — like how long it lived, how long it took to grow, how much food it ate, and how big its eggs and babies were.
"And not just those facts, but how we were able to figure this stuff out, is really the force behind the exhibit," says Norell. "It goes through the process of discovery and why we think we can calculate these numbers like the heart beating only a few times per minute."
A re-creation of another sauropod, the Argentinosaurus, will greet guests as they enter the exhibit. Or its neck and head — the size of a large garbage can — will, anyway.
"It will be peering at you through the forest," Norell reveals. "It's the largest [land] animal that we know of right now."
Not much is known about the Argen Museum exhibits, shows and walking tours are sprouting up around the boroughs this spring, and some are definitely more thrilling than others. From a BubbleMania show in Queens, to a display of daring designs by the late
Alexander McQueen, here are the most exciting of the bunch:
It's open this weekend through April 29 at the Coney Island Museum, 1208 Surf Ave., Brooklyn. Museum entrance costs just 99 cents, but the live acts will cost extra. For more info, visit spectacularium.org.tinosaurus. "The animal is so big that it's rather incompletely excavated," he adds. "It's about 150 feet long," the length of several school buses.
There are lots of interactive, hands-on aspects to the exhibit that let visitors do math experiments to figure things out about how these dinosaurs lived and even what color they might have been.
But there will also be actual sauropod fossils on display.
"We use them to illustrate certain points, like how their bones evolved to compensate for this great size," Norell explains. "We have quite a few real bones of things like a Barosaurus. We have a Diplodocus skull on display. They're not just for, 'Wow, this is a real fossil.' We use those to point to particular aspects of their anatomy and talk about some of the evolutionary and ecological attributes that these animals had."
While most exhibits have a hands-off policy, there will be some touch-me specimens. "Among those, we have the teeth of the Diplodocus, the teeth of the Camarasaurus and dinosaur egg shells which you can touch," says Norell.
The museum's permanent dinosaur exhibit, completed in 1996 and upgraded last year, is still its most-visited gallery. While the longstanding exhibit highlights the relationships among different dinosaurs, the new one focuses on the biology of a particular type.
"This is a very different kind of dinosaur show and one that allows you to really visualize these animals as living, breathing creatures," says Norell, "and not just as bones."
Alexander McQueen: Savage Beauty
The Costume Institute at the Metropolitan Museum of Art has organized about 100 examples of Alexander McQueen's work (l). They cover everything from the British designer's postgraduate collection of 1992 to his final runway presentation, which took place after his death last year. Some of his signature designs on display will be his bumster trouser, kimono jacket and origami frock coat. Also on view are his pieces that reflect the exaggerated silhouettes of the 1860s, 1880s, 1890s and 1950s.
The exhibit runs May 4-July 31, and the cost is included with admission
to the Met (1000 Fifth Ave., at 82nd St.). Adults $20, seniors (65 and over) $15, students $10, kids under 12 accompanied by an adult are free.
BubbleMania: Science, Art & Comedy! with Casey Carle
Every kid likes bubbles. But even adults enjoy the sudsy fun of the BubbleMania show. It's led by Casey Carle (l.), who went to Ringling Bros. Clown College and has worked as a bubble consultant for companies like Cirque du Soleil and Discovery Channel. During the 30-minute show, he'll form fog bubbles, funky foam, helium bubbles, vortex bubbles and bubbles that burst into flames. Carle even uses a huge Hoberman sphere to create bubbles. After the show, kids and their families can head to the permanent Bubble Table at the New York Hall of Science to make their own.
BubbleMania runs April 16-24 at the Hall of Science (47-01 111th St., Queens). Showtimes are at 1 & 2 p.m.; additional performances April 22 at 3 p.m. and April 24 at noon. BubbleMania is $4, plus admission dinomight!
An awe-inspiring new exhibit sizes up the life of the gigantic creatures to the Hall (nysci.org), which is $11 for adults and $8 for kids.
Monday, April 11, 2011
Thursday, April 7, 2011
As Dinosaurs Waned and Mammals Rose, the Lowly Louse Kept Pace
The New York Times: As Dinosaurs Waned and Mammals Rose, the Lowly Louse Kept Pace
Biologists have found a new way to peer back 130 million years in time, illuminating the catastrophic period in which the dinosaurs perished and birds and mammals arose.
The new approach rests on reconstructing the family tree of lice. Vincent S. Smith, a louse taxonomist at the Natural History Museum in London, has found that the tree stretches so far back in time that the host of the first louse would have been a dinosaur, probably one of the theropod dinosaurs that were the ancestors of birds.
Dr. Smith and his colleagues reconstructed the louse family tree by analyzing DNA from present-day louse species that parasitize birds and mammals. Most lice are specialists, feeding on a single species to whose fur or feathers their claws are adapted. The adaptation is so precise that when a louse’s host species evolves into a new one, the louse will diversify into different species, too.
The human head louse, for instance, evolved from the chimpanzee louse when the ancestors of humans and chimps split apart some five million years ago. The human pubic louse, on the other hand, is related to the gorilla louse, from which it parted company some 13 million years ago. Species of human lice thus mirror the splits in the tree of ape and human evolution.
In the same way, species of lice on living animals and birds reflect the splits in animal and bird ancestry back to the time that lice first arose. Family trees based on DNA can be given precise dates at all their branch points if a few datable fossils of the right age are available. But this is difficult to do with lice, for which almost no fossils are known. Dr. Smith was fortunate that two fossil lice discovered in the last few years — one of them 44 million and the other 100 million years old — provided the necessary anchors for his tree.
The assembled family tree shows that lice started to radiate into new species well before the end of the Cretaceous period, Dr. Smith and his colleagues report in the current issue of Biology Letters. The finding implies that their hosts, both mammals and birds, had also begun to flourish and speciate before the reign of the dinosaurs was over.
The new tree bears on a longstanding dispute about the rise of birds and mammals. One school holds that both groups proliferated early in the Cretaceous period, which began 145 million years ago, and that many lineages survived the cataclysm that brought the Cretaceous and the dinosaurs to a sudden end: the strike of a large asteroid 65 million years ago. The opposing view is that mammals and birds did not become successful and radiate into many different species until after the demise of the dinosaurs.
Unfortunately, the new finding will probably not settle the issue of whether birds and mammals speciated before or after the asteroid hit. “I would put this down as an entry in the debate,” Dr. Smith said. “The louse phylogeny adds one more piece of data to this puzzle. It says lice are old, predate the Cretaceous-Paleogene boundary, and must have been living on something.”
The issue is contentious because the fossil record suggests that placental mammals did not expand, in terms of the number of different species, until after 65 million years ago. A plausible reason is that all the dinosaurs had been killed off, except the line that evolved into birds, and the placental mammals speciated into the ecological niches that had been left vacant.
But biologists reconstructing the mammalian tree of evolution from the DNA of living species have come to a different conclusion. Their molecular clock data suggest a much earlier speciation, perhaps prompted by the breakup of the ancient supercontinent of Gondwana around 120 million years ago. In this view, placental mammals evolved into distinct species before the asteroid hit of 65 million years ago, and many would have survived the mass die-out that polished off the dinosaurs.
Michael Novacek, an expert in mammalian paleontology at the American Museum of Natural History in New York, said the louse tree was very interesting and showed that lice were diversifying during the Cretaceous. But the fossil record of placental mammals is reliable and does not record a speciation until later. “The fossil record continues to show that the origin of modern placental mammals postdates or is at the Cretaceous-Paleogene boundary,” he said. “So the contradiction between the fossils and molecular clocks remains.”
In his view, the hosts on which lice were speciating during the Cretaceous could have been a different branch of the mammalian family tree, all of whose species are extinct.
Dr. Smith said Dr. Novacek was correct in saying that there were nonplacental mammals around in the Cretaceous on which lice would doubtless have fed. But these nonplacental mammals, which included several lineages of marsupials, all became extinct, taking their parasites with them. These lice would not show up in his tree, Dr. Smith said, unless they had been able to transfer to the placental mammalian species, and most lice do not regularly switch hosts.
Dr. Smith believes that lice infested birds before mammals, in part because lice are so common on birds. Every bird family but one has lice, and there is a species of bird, the great tinamou, that harbors 18 different species of lice, perhaps because it has many different kinds of feathers, each offering a special niche. Given the ancient root of the louse family tree, it is likely that the first louse infested the feathered dinosaurs that were the birds’ ancestors, he concludes.
Biologists have found a new way to peer back 130 million years in time, illuminating the catastrophic period in which the dinosaurs perished and birds and mammals arose.
The new approach rests on reconstructing the family tree of lice. Vincent S. Smith, a louse taxonomist at the Natural History Museum in London, has found that the tree stretches so far back in time that the host of the first louse would have been a dinosaur, probably one of the theropod dinosaurs that were the ancestors of birds.
Dr. Smith and his colleagues reconstructed the louse family tree by analyzing DNA from present-day louse species that parasitize birds and mammals. Most lice are specialists, feeding on a single species to whose fur or feathers their claws are adapted. The adaptation is so precise that when a louse’s host species evolves into a new one, the louse will diversify into different species, too.
The human head louse, for instance, evolved from the chimpanzee louse when the ancestors of humans and chimps split apart some five million years ago. The human pubic louse, on the other hand, is related to the gorilla louse, from which it parted company some 13 million years ago. Species of human lice thus mirror the splits in the tree of ape and human evolution.
In the same way, species of lice on living animals and birds reflect the splits in animal and bird ancestry back to the time that lice first arose. Family trees based on DNA can be given precise dates at all their branch points if a few datable fossils of the right age are available. But this is difficult to do with lice, for which almost no fossils are known. Dr. Smith was fortunate that two fossil lice discovered in the last few years — one of them 44 million and the other 100 million years old — provided the necessary anchors for his tree.
The assembled family tree shows that lice started to radiate into new species well before the end of the Cretaceous period, Dr. Smith and his colleagues report in the current issue of Biology Letters. The finding implies that their hosts, both mammals and birds, had also begun to flourish and speciate before the reign of the dinosaurs was over.
The new tree bears on a longstanding dispute about the rise of birds and mammals. One school holds that both groups proliferated early in the Cretaceous period, which began 145 million years ago, and that many lineages survived the cataclysm that brought the Cretaceous and the dinosaurs to a sudden end: the strike of a large asteroid 65 million years ago. The opposing view is that mammals and birds did not become successful and radiate into many different species until after the demise of the dinosaurs.
Unfortunately, the new finding will probably not settle the issue of whether birds and mammals speciated before or after the asteroid hit. “I would put this down as an entry in the debate,” Dr. Smith said. “The louse phylogeny adds one more piece of data to this puzzle. It says lice are old, predate the Cretaceous-Paleogene boundary, and must have been living on something.”
The issue is contentious because the fossil record suggests that placental mammals did not expand, in terms of the number of different species, until after 65 million years ago. A plausible reason is that all the dinosaurs had been killed off, except the line that evolved into birds, and the placental mammals speciated into the ecological niches that had been left vacant.
But biologists reconstructing the mammalian tree of evolution from the DNA of living species have come to a different conclusion. Their molecular clock data suggest a much earlier speciation, perhaps prompted by the breakup of the ancient supercontinent of Gondwana around 120 million years ago. In this view, placental mammals evolved into distinct species before the asteroid hit of 65 million years ago, and many would have survived the mass die-out that polished off the dinosaurs.
Michael Novacek, an expert in mammalian paleontology at the American Museum of Natural History in New York, said the louse tree was very interesting and showed that lice were diversifying during the Cretaceous. But the fossil record of placental mammals is reliable and does not record a speciation until later. “The fossil record continues to show that the origin of modern placental mammals postdates or is at the Cretaceous-Paleogene boundary,” he said. “So the contradiction between the fossils and molecular clocks remains.”
In his view, the hosts on which lice were speciating during the Cretaceous could have been a different branch of the mammalian family tree, all of whose species are extinct.
Dr. Smith said Dr. Novacek was correct in saying that there were nonplacental mammals around in the Cretaceous on which lice would doubtless have fed. But these nonplacental mammals, which included several lineages of marsupials, all became extinct, taking their parasites with them. These lice would not show up in his tree, Dr. Smith said, unless they had been able to transfer to the placental mammalian species, and most lice do not regularly switch hosts.
Dr. Smith believes that lice infested birds before mammals, in part because lice are so common on birds. Every bird family but one has lice, and there is a species of bird, the great tinamou, that harbors 18 different species of lice, perhaps because it has many different kinds of feathers, each offering a special niche. Given the ancient root of the louse family tree, it is likely that the first louse infested the feathered dinosaurs that were the birds’ ancestors, he concludes.
Monday, March 7, 2011
Englishman hunts dinosaurs for hobby
SFGate: Englishman hunts dinosaurs for hobby
Last week, Mike Taylor identified a new dinosaur called Brontomerus mcintoshi, a sauropod with uncommonly large, powerful thighs.
It is the second dinosaur he has named in five years and his 13th paleontology publication.
That would be impressive, although not unusual, for a hardworking full-time paleontologist. But Mike Taylor is a 42-year-old British computer programmer who writes code for a living in a quaint English village called Ruardean.
Hunting for dinosaurs is merely a hobby, albeit one he pursues seriously.
One day 10 years ago, while reading a paleontology paper on a long plane trip, he had an epiphany.
"I thought, well, blimey, I could do better than that," he said. "And then I decided, why shouldn't I? What's stopping me?"
His childhood interest in dinosaurs was rekindled in 2000, and he got hold of classic books like "The Dinosaur Heresies," "The Complete Dinosaur" and the "Dinosaur Encyclopedia." He amassed a collection of paleontology journals and studied them with the intensity of a graduate student.
Taylor, whose numerous papers earned him a formal doctorate in paleontology in 2009 from the University of Portsmouth, is not alone in his love for dinosaurs. The public has long had a fascination for the magnificent creatures that lived millions of years ago, some dwarfing elephants in size.
"There are many dino fan boys out there," Taylor said. "And I was just another one of them."
His latest discovery, Brontomerus mcintoshi, is named after John McIntosh, one other such "fan boy."
McIntosh spent his career as a physics professor at Wesleyan. He spent his spare hours poring over bones in museums around the world. And when he retired 20 years ago, he devoted himself to the study of sauropods, the order of large, plant-eating dinosaurs that Taylor also favors.
Over the course of more than 30 years, McIntosh made major contributions to the field, writing many papers and several books. In 1979, he helped prove that paleontologists had mounted the wrong head on a sauropod named apatosaurus. "Even a minor paleontologist can make a major contribution," Taylor said.
Other scientific disciplines, like physics and genetics, require fancy equipment, large labs and major funding. Although paleontology has come to depend more and more on CT scans and even molecular analyses, it still has plenty of room for the time-honored pursuit of puzzling through bones and piecing them together.
"You just need a decent camera, a little time and money to travel to museums, some experience, a good eye," said Nicholas Longrich, a paleontologist at Yale. "It's still hard - not just anybody can do it - but the barrier to entry is a lot lower than for other fields."
Taylor has not participated in an excavation, instead choosing to study the scores of unnamed fossils that are collecting dust in the basements of museums. He takes pictures from many angles and makes detailed measurements that he studies.
"Given the limited time I have available for paleo, conferences and museum visits are more important," he said.
His first discovery, a bone belonging to an elephant-size herbivorous dinosaur called xenoposeidon, was excavated in the early 1890s. It was acquired by the Natural History Museum in London and remained unidentified until Taylor began studying it.
And the dinosaur he recently named was found at a site in Utah in 1995 and housed in the Sam Noble Oklahoma Museum of Natural History, unidentified.
"Our museums are chock-full of things that have never been studied, or explained at all," said Mathew Wedel, a paleontologist and anatomist at Western University of Health Sciences and Taylor's co-author on the Brontomerus paper.
He and Taylor became pen pals 10 years ago, when Taylor sent him an e-mail about one of his publications.
They then began brainstorming and sharing ideas. The two are now best friends and usually meet about once a year at paleontology conferences and museums to collaborate.
Last week, Mike Taylor identified a new dinosaur called Brontomerus mcintoshi, a sauropod with uncommonly large, powerful thighs.
It is the second dinosaur he has named in five years and his 13th paleontology publication.
That would be impressive, although not unusual, for a hardworking full-time paleontologist. But Mike Taylor is a 42-year-old British computer programmer who writes code for a living in a quaint English village called Ruardean.
Hunting for dinosaurs is merely a hobby, albeit one he pursues seriously.
One day 10 years ago, while reading a paleontology paper on a long plane trip, he had an epiphany.
"I thought, well, blimey, I could do better than that," he said. "And then I decided, why shouldn't I? What's stopping me?"
His childhood interest in dinosaurs was rekindled in 2000, and he got hold of classic books like "The Dinosaur Heresies," "The Complete Dinosaur" and the "Dinosaur Encyclopedia." He amassed a collection of paleontology journals and studied them with the intensity of a graduate student.
Taylor, whose numerous papers earned him a formal doctorate in paleontology in 2009 from the University of Portsmouth, is not alone in his love for dinosaurs. The public has long had a fascination for the magnificent creatures that lived millions of years ago, some dwarfing elephants in size.
"There are many dino fan boys out there," Taylor said. "And I was just another one of them."
His latest discovery, Brontomerus mcintoshi, is named after John McIntosh, one other such "fan boy."
McIntosh spent his career as a physics professor at Wesleyan. He spent his spare hours poring over bones in museums around the world. And when he retired 20 years ago, he devoted himself to the study of sauropods, the order of large, plant-eating dinosaurs that Taylor also favors.
Over the course of more than 30 years, McIntosh made major contributions to the field, writing many papers and several books. In 1979, he helped prove that paleontologists had mounted the wrong head on a sauropod named apatosaurus. "Even a minor paleontologist can make a major contribution," Taylor said.
Other scientific disciplines, like physics and genetics, require fancy equipment, large labs and major funding. Although paleontology has come to depend more and more on CT scans and even molecular analyses, it still has plenty of room for the time-honored pursuit of puzzling through bones and piecing them together.
"You just need a decent camera, a little time and money to travel to museums, some experience, a good eye," said Nicholas Longrich, a paleontologist at Yale. "It's still hard - not just anybody can do it - but the barrier to entry is a lot lower than for other fields."
Taylor has not participated in an excavation, instead choosing to study the scores of unnamed fossils that are collecting dust in the basements of museums. He takes pictures from many angles and makes detailed measurements that he studies.
"Given the limited time I have available for paleo, conferences and museum visits are more important," he said.
His first discovery, a bone belonging to an elephant-size herbivorous dinosaur called xenoposeidon, was excavated in the early 1890s. It was acquired by the Natural History Museum in London and remained unidentified until Taylor began studying it.
And the dinosaur he recently named was found at a site in Utah in 1995 and housed in the Sam Noble Oklahoma Museum of Natural History, unidentified.
"Our museums are chock-full of things that have never been studied, or explained at all," said Mathew Wedel, a paleontologist and anatomist at Western University of Health Sciences and Taylor's co-author on the Brontomerus paper.
He and Taylor became pen pals 10 years ago, when Taylor sent him an e-mail about one of his publications.
They then began brainstorming and sharing ideas. The two are now best friends and usually meet about once a year at paleontology conferences and museums to collaborate.
Could today's plants and animals go the way of dinosaurs? New study says yes
Medill Reports: Could today's plants and animals go the way of dinosaurs? New study says yes
by Michelle M. Schaefer
March 04, 2011
The Earth may be on the verge of a sixth mass extinction, a new study finds. That means more than 75 percent of the world’s creatures could disappear in as little as 300 years.
The cause for this Armageddon isn’t an asteroid, believed to have driven the dinosaurs to extinction 65 million years ago. Human land use and climate change are directly to blame, according to study researchers.
“What we discovered is both good news and bad news. We have not caused so much extinction that we should lose hope. But the bad news is that, if we don’t slow down the highly elevated rates of extinction today, we could be looking at the sixth mass extinction in as little as three to 22 centuries,” said Tony Barnosky, a paleontologist at the University of California, Berkley, who led the study. The findings were reported this week in the journal Nature online.
“The cause of this mass extinction is clearly us. And the way we’re doing that is by fragmenting habitats, by climate change that is largely human caused, by moving species around the Earth so that invasive species take over places where the endemic species of an area would normally live," said Barnosky. Add to that the growing population on the planet and the resources we consume, he said.
A mass extinction is characterized by a short period of time when the Earth loses more than three-quarters of its species. The Earth has experienced five mass extinctions over the last 540 million years, the most commonly known being the extinction of the dinosaurs and other species in the fifth mass extinction.
The other four mass extinctions all occurred before the dinosaurs became extinct. Creatures lost during these extinctions impacted invertebrate marine animals, similar to clams, snails, coral and relatives of starfish.
Barnosky said no group of organisms is safe from the current extinction. Some of the current animals on the endangered species list include rhinoceros, elephants, giant pandas, whales, dolphins, tigers, marine turtles and tree kangaroos.
“There are species in just about every category of plants and animals that you are familiar with, so mammals reptiles, amphibians, birds, fish, many different kinds of plants. It seems like no matter what kind of group of organisms we do this assessment on, we come up with numbers that threatened species are in the range of 20 percent to 50 percent,” he said.
David Jablonski, a paleontologist at the University of Chicago in Illinois, who was not involved with the study, explained that this is one of the first rigorous attempts to compare the current extinction to that of the fossil record.
Researchers completed a mathematical analysis of the existing data for the modern record of species and the fossil record to compare the current rate of extinction to past mass extinctions.
“That’s actually a very difficult thing to do. The fossil record involves courser time frames and it involves a different kind of spatial coverage and at the same time of course it shows much more extreme extinction then we have so far. So the question is: What would it look like? What would today’s patterns look like if we extended them through a block of geological time?” Jablonski said.
The study estimated that four billion species have evolved on Earth over the last 3.5 billion years and about 99 percent of them are extinct. This shows that extinction is actually a common occurrence.
“So far we haven’t hit the massive amount of loss that we’d see in the fossil record, which is a very fortunate thing for all of us. But, at the same time, we’re doing our darndest to push the biosphere over into that kind of extinction spasm and that’s bad news,” he said.
A natural disaster could easily cause another mass extinction. However, current elevated extinction levels are linked to human activity and that gives people a choice, Barnosky said. He said the good news is, if people change their habits and implement effective conservation methods, there’s still time to save potentially threatened species.
“We still have most of earth’s biodiversity left to save and that’s actually in our grasp to do that. We can avoid this sixth mass extinction,” said Barnosky.
by Michelle M. Schaefer
March 04, 2011
The Earth may be on the verge of a sixth mass extinction, a new study finds. That means more than 75 percent of the world’s creatures could disappear in as little as 300 years.
The cause for this Armageddon isn’t an asteroid, believed to have driven the dinosaurs to extinction 65 million years ago. Human land use and climate change are directly to blame, according to study researchers.
“What we discovered is both good news and bad news. We have not caused so much extinction that we should lose hope. But the bad news is that, if we don’t slow down the highly elevated rates of extinction today, we could be looking at the sixth mass extinction in as little as three to 22 centuries,” said Tony Barnosky, a paleontologist at the University of California, Berkley, who led the study. The findings were reported this week in the journal Nature online.
“The cause of this mass extinction is clearly us. And the way we’re doing that is by fragmenting habitats, by climate change that is largely human caused, by moving species around the Earth so that invasive species take over places where the endemic species of an area would normally live," said Barnosky. Add to that the growing population on the planet and the resources we consume, he said.
A mass extinction is characterized by a short period of time when the Earth loses more than three-quarters of its species. The Earth has experienced five mass extinctions over the last 540 million years, the most commonly known being the extinction of the dinosaurs and other species in the fifth mass extinction.
The other four mass extinctions all occurred before the dinosaurs became extinct. Creatures lost during these extinctions impacted invertebrate marine animals, similar to clams, snails, coral and relatives of starfish.
Barnosky said no group of organisms is safe from the current extinction. Some of the current animals on the endangered species list include rhinoceros, elephants, giant pandas, whales, dolphins, tigers, marine turtles and tree kangaroos.
“There are species in just about every category of plants and animals that you are familiar with, so mammals reptiles, amphibians, birds, fish, many different kinds of plants. It seems like no matter what kind of group of organisms we do this assessment on, we come up with numbers that threatened species are in the range of 20 percent to 50 percent,” he said.
David Jablonski, a paleontologist at the University of Chicago in Illinois, who was not involved with the study, explained that this is one of the first rigorous attempts to compare the current extinction to that of the fossil record.
Researchers completed a mathematical analysis of the existing data for the modern record of species and the fossil record to compare the current rate of extinction to past mass extinctions.
“That’s actually a very difficult thing to do. The fossil record involves courser time frames and it involves a different kind of spatial coverage and at the same time of course it shows much more extreme extinction then we have so far. So the question is: What would it look like? What would today’s patterns look like if we extended them through a block of geological time?” Jablonski said.
The study estimated that four billion species have evolved on Earth over the last 3.5 billion years and about 99 percent of them are extinct. This shows that extinction is actually a common occurrence.
“So far we haven’t hit the massive amount of loss that we’d see in the fossil record, which is a very fortunate thing for all of us. But, at the same time, we’re doing our darndest to push the biosphere over into that kind of extinction spasm and that’s bad news,” he said.
A natural disaster could easily cause another mass extinction. However, current elevated extinction levels are linked to human activity and that gives people a choice, Barnosky said. He said the good news is, if people change their habits and implement effective conservation methods, there’s still time to save potentially threatened species.
“We still have most of earth’s biodiversity left to save and that’s actually in our grasp to do that. We can avoid this sixth mass extinction,” said Barnosky.
Friday, March 4, 2011
REDLANDS: Learn how some dinosaurs got so big
The Press Enterprise (San Bernardino, CA): REDLANDS: Learn how some dinosaurs got so big
Ever wonder why dinosaurs were so big?
Guest speaker Matt Wedel, a paleontologist who has studied giant dinosaurs for the last 15 years, will answer that question and more in his lecture, "All-time Giants: How the Largest Dinosaurs Got So Big" at 7:30 p.m. March 23.
The lecture at the San Bernardino County Museum is free.
The immense size of some dinosaurs has been a source of popular fascination -- and a scientific puzzle -- since the earliest discoveries were made. In recent years, paleontologists have unearthed more fossils of record-breaking animals, and discovered some answers to the questions of how and why they got so big.
Wedel, an assistant professor in the Department of Anatomy at Western University of Health Sciences in Pomona, will explain why some dinosaurs stopped chewing their food, got pregnant as teenagers and abandoned their babies so they could go big.
Air-filled bones, buried eggs, elephant poop and sheep that eat seaweed all are part of the scientific quest to understand the world's largest land animals.
Joan Marcus / Special to The Press-Enterprise
Fascination of large dinosaurs has inspired shows like "Walking With Dinosaurs."
In addition to teaching, Wedel frequently appears in documentaries on the Discovery Channel, Animal Planet and the History Channel.
The program is part of a series of free guest lectures at the museum. Upcoming speakers are David Earle on "Mission Baskets," April 27, Mark Springer on "Tooth Loss and Molecular Cavities in Placental Mammals," May 25, and Anthony Metcalk on "Processes That Affect Genetic Diversity," June 22.
Ever wonder why dinosaurs were so big?
Guest speaker Matt Wedel, a paleontologist who has studied giant dinosaurs for the last 15 years, will answer that question and more in his lecture, "All-time Giants: How the Largest Dinosaurs Got So Big" at 7:30 p.m. March 23.
The lecture at the San Bernardino County Museum is free.
The immense size of some dinosaurs has been a source of popular fascination -- and a scientific puzzle -- since the earliest discoveries were made. In recent years, paleontologists have unearthed more fossils of record-breaking animals, and discovered some answers to the questions of how and why they got so big.
Wedel, an assistant professor in the Department of Anatomy at Western University of Health Sciences in Pomona, will explain why some dinosaurs stopped chewing their food, got pregnant as teenagers and abandoned their babies so they could go big.
Air-filled bones, buried eggs, elephant poop and sheep that eat seaweed all are part of the scientific quest to understand the world's largest land animals.
Joan Marcus / Special to The Press-Enterprise
Fascination of large dinosaurs has inspired shows like "Walking With Dinosaurs."
In addition to teaching, Wedel frequently appears in documentaries on the Discovery Channel, Animal Planet and the History Channel.
The program is part of a series of free guest lectures at the museum. Upcoming speakers are David Earle on "Mission Baskets," April 27, Mark Springer on "Tooth Loss and Molecular Cavities in Placental Mammals," May 25, and Anthony Metcalk on "Processes That Affect Genetic Diversity," June 22.
TED 2011: Hatching Dinosaurs, One Egg at a Time
Wired: TED 2011: Hatching Dinosaurs, One Egg at a Time
LONG BEACH, California — You know the scene in Jurassic Park. Sam Neil’s character Dr. Alan Grant and a group of naïve visitors enter the dinosaur island’s birthing lab just at the moment a large egg begins to wobble and crack. The determined creature inside pecks its way out of the shell, and suddenly a velociraptor is born – more than 70 million years after its species was supposed to have become extinct.
Only in the movies, right?
Not if you’re paleontologist Jack Horner, the inspiration for Neil’s character, who is on a mission to bring dinosaurs back – or at least the modern-day version of one.
Horner, curator of paleontology at the Museum of the Rockies and regent’s professor at Montana State University, has been working with researchers to produce a dino-chicken or chickensaurus — a chicken with prehistoric features such as a tail and hands. The research has been featured on 60 Minutes and elsewhere.
Chickens, and other birds, are descendants of dinosaurs and carry the dino DNA. In the embryo stage, chickens actually have a tail, which disappears before the bird hatches. Horner believes that if researchers can find the gene that turns off the tail — and turn it back on — they can hatch a chicken that resembles a dinosaur.
Horner will be speaking about his work at the Technology Entertainment and Design conference on Friday. He talked about his dino project with Wired.com in advance of his presentation.
Wired.com: Why did you choose a chicken for your experiment and not an ostrich or some other bird? Is there a reason a chicken is more suitable?
Jack Horner: They’re easier to come by. Ostriches cost a lot of money. That really is the only reason. And the generation time is quicker. A chicken grows up in a little less time than an ostrich. An ostrich takes a whole year. A chicken takes a few months. You’d probably be better off using a smaller bird, but there gets to be some logistical problems with them. You can go and get plenty of eggs of chickens, but it’s pretty hard to go and get plenty of eggs of robins.
LONG BEACH, California — You know the scene in Jurassic Park. Sam Neil’s character Dr. Alan Grant and a group of naïve visitors enter the dinosaur island’s birthing lab just at the moment a large egg begins to wobble and crack. The determined creature inside pecks its way out of the shell, and suddenly a velociraptor is born – more than 70 million years after its species was supposed to have become extinct.
Only in the movies, right?
Not if you’re paleontologist Jack Horner, the inspiration for Neil’s character, who is on a mission to bring dinosaurs back – or at least the modern-day version of one.
Horner, curator of paleontology at the Museum of the Rockies and regent’s professor at Montana State University, has been working with researchers to produce a dino-chicken or chickensaurus — a chicken with prehistoric features such as a tail and hands. The research has been featured on 60 Minutes and elsewhere.
Chickens, and other birds, are descendants of dinosaurs and carry the dino DNA. In the embryo stage, chickens actually have a tail, which disappears before the bird hatches. Horner believes that if researchers can find the gene that turns off the tail — and turn it back on — they can hatch a chicken that resembles a dinosaur.
Horner will be speaking about his work at the Technology Entertainment and Design conference on Friday. He talked about his dino project with Wired.com in advance of his presentation.
Wired.com: Why did you choose a chicken for your experiment and not an ostrich or some other bird? Is there a reason a chicken is more suitable?
Jack Horner: They’re easier to come by. Ostriches cost a lot of money. That really is the only reason. And the generation time is quicker. A chicken grows up in a little less time than an ostrich. An ostrich takes a whole year. A chicken takes a few months. You’d probably be better off using a smaller bird, but there gets to be some logistical problems with them. You can go and get plenty of eggs of chickens, but it’s pretty hard to go and get plenty of eggs of robins.
Tuesday, March 1, 2011
Dinosaur Bones Dating Back 72 Million Years Found in Mexico
Fox News Latino: Dinosaur Bones Dating Back 72 Million Years Found in Mexico
Paleontologists have found in the desert of Coahuila, a state in northern Mexico, fragments of vertebrae and long bones that could have belonged to a species of dinosaur that lived in the region 72 million years ago during the late Cretaceous period, officials said.
The fossils could come from species that once inhabited the area, such as the Hadrosauridae, or duck-billed dinosaur, the Ornitomimidae, a biped similar to the ostrich, and Tyrannosaurus, said the National Anthropology and History Institute, or INAH.
The bones were discovered by INAH paleontologists at the city of General Cepeda in the Coahuila desert, which is on the border with the United States.
The remains of prehistoric fauna were found in a paleontological deposit called Las Aguilas while tasks of cleaning and conservation of the site were being performed.
The fossils were fragments of vertebrae and long bones, probably femurs, which were found at several points on the site that covers some 53,750 sq. feet, said INAH-Coahuila Center paleontologist Felisa Aguilar, who is in charge of conservation and research at the deposit.
Related Links
New Species of Dinosaur Discovered in Argentina Some 207 footprints have been found in the area, left by dinosaurs that lived around 72 million years ago.
"It is not yet possible to provide details of the type of species these bones belonged to, since their state of fragmentation requires more detailed study," Aguilar said.
It's very probable the fossils belong to individuals of the duck-billed dinosaur, Ornitomimidae and Tyrannosaurus families, because "from the footprints at the site, we know that they lived there," Aguilar said.
Following this discovery, the paleontologists did a study of the area surrounding Las Aguilas and came up with another three places where dinosaurs had left their footprints.
"Those places are still hidden under vegetation and won't be opened to the public until they are registered so that their future conservation can be guaranteed," Agilar said.
Paleontological remains more than 70 million years old have been found on 90 percent of the site at General Cepeda, and on 5 percent of it have been discovered vestiges of the Pleistocene, a geological period dating from 2.5 million years to 10,000 years ago.
Paleontologists have found in the desert of Coahuila, a state in northern Mexico, fragments of vertebrae and long bones that could have belonged to a species of dinosaur that lived in the region 72 million years ago during the late Cretaceous period, officials said.
The fossils could come from species that once inhabited the area, such as the Hadrosauridae, or duck-billed dinosaur, the Ornitomimidae, a biped similar to the ostrich, and Tyrannosaurus, said the National Anthropology and History Institute, or INAH.
The bones were discovered by INAH paleontologists at the city of General Cepeda in the Coahuila desert, which is on the border with the United States.
The remains of prehistoric fauna were found in a paleontological deposit called Las Aguilas while tasks of cleaning and conservation of the site were being performed.
The fossils were fragments of vertebrae and long bones, probably femurs, which were found at several points on the site that covers some 53,750 sq. feet, said INAH-Coahuila Center paleontologist Felisa Aguilar, who is in charge of conservation and research at the deposit.
Related Links
New Species of Dinosaur Discovered in Argentina Some 207 footprints have been found in the area, left by dinosaurs that lived around 72 million years ago.
"It is not yet possible to provide details of the type of species these bones belonged to, since their state of fragmentation requires more detailed study," Aguilar said.
It's very probable the fossils belong to individuals of the duck-billed dinosaur, Ornitomimidae and Tyrannosaurus families, because "from the footprints at the site, we know that they lived there," Aguilar said.
Following this discovery, the paleontologists did a study of the area surrounding Las Aguilas and came up with another three places where dinosaurs had left their footprints.
"Those places are still hidden under vegetation and won't be opened to the public until they are registered so that their future conservation can be guaranteed," Agilar said.
Paleontological remains more than 70 million years old have been found on 90 percent of the site at General Cepeda, and on 5 percent of it have been discovered vestiges of the Pleistocene, a geological period dating from 2.5 million years to 10,000 years ago.
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