[naturenews] from [nature.com]
[naturenews]
Published online 23 December 2009 | Nature | doi:10.1038/news.2009.1160
News
Fossil evidence of early reptiles' last meal
Insect remains found in the mouths of early vertebrate fossils.
Janelle Weaver
{{The jaws of two fossils may be harbouring evidence that early reptiles fed on insects.}
Biology Letters}
In the caves of a hilly Oklahoma ghost town, researchers have found what may be the first evidence of preserved insect remains in the mouths of fossilized vertebrates. The find is compelling evidence that early reptiles, the equivalent of modern-day lizards, fed on insects.
Sean Modesto, a biologist at Cape Breton University in Nova Scotia, Canada, and his colleagues found pieces of arthropod skeleton on the teeth inside two 280-million-year-old skulls of a species of reptile they have yet to fully describe. They report the discovery in the journal Biology Letters1.
One skull contained a cuticle with five segments that seemed to be part of an antenna, and the other had a long cuticle fragment that was narrow at one end and broader at the tip. This could have been part of a rear appendage.
"It is extremely uncommon to find the remains of organisms in the mouths of fossilized predators," says Matthew Vickaryous, who studies the anatomy of fossil vertebrates at the University of Guelph in Ontario, Canada. "To the best of my knowledge, this is a one of a kind find."
Lucky find
Modesto and his collaborators made this discovery entirely by chance. "You don't expect to see the last meal lodged in the teeth of fossils," Modesto says. "The modern equivalent is finding a popcorn kernel shell in the tooth of an ancient Mayan."
The two skulls come from an enigmatic group called parareptiles, which first appeared nearly 300 million years ago and for the most part became extinct by the end of the Permian period, with just a few species lingering into the age of dinosaurs.
{{What seem to be remains of an antenna and a rear appendage of insects have been found on the fossils' teeth.}
Biology Letters}
"To have pieces of both vertebrate and invertebrate preserved at the same time is very unusual," Vickaryous says. Vertebrate palaeontologists may overlook small pieces of invertebrate remains when excavating spectacular vertebrate fossils. Beyond the initial detection, preserving the remains requires careful recovery and preparation, he adds.
In younger specimens, researchers have found mollusc shell fragments in the gut of a fossil sea turtle2, preserved fish remains in a bird's stomach3, lizard and mammal skeletons in fossil dinosaur stomachs4 and dinosaur remains in a fossil mammal's stomach5. In fossil reptiles from the Permian, scientists have found plant material in the gut6 and reptile bones in the mouth7.
But little other evidence is available for the dietary habits of the vertebrates that lived during the Permian, says Conrad Labandeira, palaeoecologist at the National Museum of Natural History in Washington DC. "This paper may be more important in the long run than the original description of the fossil bones."
Insectivorous evidence
Roy Beckemeyer, palaeoentomologist at the University of Kansas Natural History Museum in Lawrence, has studied Permian insect fossils in Oklahoma. He evaluated photographs of the finds and verified that the fragments were from an arthropod. "We know of roughly 200 species of insects in this area during that time," Beckemeyer says. "There's a very good chance that these reptiles were insectivorous."
Scientists had long suspected that early reptiles were insectivorous because of the shape of their teeth, which are sharp and curve inward, making them ideal for piercing insect skeletons and holding struggling prey in place. But that evidence is indirect because it relies on comparisons between extinct and living animals.
"It's pretty much smoking-gun type of evidence when you actually have the organism in the part of the anatomy responsible for feeding," Labandeira says. "It's very compelling evidence that closes the case."
References
1. Modesto, S. P. , Scott, D. M. & Reisz, R. R. Biol. Lett. 5, 838-840 (2009).
2. Kear, B. P. Biol. Lett. 2, 113-115 (2006).
3. Mayr, G. J. Ornithol. 145, 281-286 (2004).
4. Currie, P. J. & Chen, P.-J. Can. J. Earth Sci. 38, 1705-1727 (2001).
5. Hu, Y. , Meng, J. , Wang, Y. & Li, C. Nature 433, 149-152 (2005).
6. Karlsruhe, W. M. & Sues, H.-D. Paläontol. Zeitschr. 67, 169-176 (1993).
7. Eaton, T. H. Jr American Museum Novitates No. 2169 (1964).
[naturenews]
Published online 23 December 2009 | Nature 462, 962-963 (2009) | doi:10.1038/462962a
News
News 2009
The year in which …
Lizzie Buchen
H1N1 swept the planet
The first influenza pandemic in 40 years propelled the globe onto a roller coaster of panic and complacency. In March, a new H1N1 virus — a mongrel containing genes from swine, bird and human flu viruses — emerged in North America and spread rapidly, sparking fears of a severe pandemic. The new virus was particularly dangerous for younger adults and those with underlying diseases, but most patients had mild symptoms. The low severity cut the world some slack, as a vaccine took months to produce and some manufacturers fell behind schedule; the United States, Australia and Europe didn't start vaccination programmes until October, and poorer nations months after that, if at all. As of mid-December the flu was continuing to intensify across central and eastern Europe and parts of Asia, but its second wave had peaked in North America and parts of Europe. More than 10,580 people have died.
The LHC broke a world record
The high-energy physics crown has passed from the United States to Europe. On 30 November the Large Hadron Collider (LHC) near Geneva, Switzerland, became the highest-energy accelerator in the world, breaking the record long held by the Tevatron at Fermilab in Batavia, Illinois. Europe's proton-pummelling behemoth had spent most of the year in recovery after an electrical failure during its first run in September 2008 caused massive damage. By December 2009, head-on collisions at the LHC had reached 2.36 teraelectronvolts; physicists plan to begin science at this energy level in 2010, with the hope of finding evidence of the long-sought Higgs boson and dark matter.
Climate e-mails were hacked
In what climate-change sceptics are calling the scandal of the decade — and many climate scientists are calling a meaningless nuisance — more than 1,000 e-mails between top researchers were hacked from the Climatic Research Unit (CRU) at the University of East Anglia, UK, just weeks before the Copenhagen climate summit began. Some of the e-mails revealed frustration with data and a cavalier attitude towards sceptics, but they did not discredit the solid body of evidence showing that the world is getting warmer, probably at the hands of humans. The e-mails did, however, embolden sceptics, who interpreted them as evidence of a global conspiracy. CRU director Phil Jones, who composed most of the more controversial e-mails, has stepped aside while an independent panel investigates.
The Moon was found to be damp
A decades-long debate has been resolved: water ice can accumulate in frigid craters on the Moon. On 9 October the rocket booster of NASA's Lunar Crater Observation and Sensing Satellite (LCROSS) slammed into a lunar crater that receives no sunlight, kicking up a plume of dust that was disappointing to spectators but exciting for scientists. Just before LCROSS crashed, its instruments detected water in the dust, suggesting that vapour had frozen into the crater floor. Other spectra hinted at other molecules, such as carbon dioxide, mercury and methane. Researchers hope to explore the ice for clues about the Solar System's history.
Obama boosted US science
"We will restore science to its rightful place," said US President Barack Obama in his inaugural address in January. On 9 March, Obama signed a memo supporting scientific integrity in federal decision-making and an executive order lifting the prior administration's limits on human embryonic stem-cell research. The latter move greatly expanded the number of cell lines eligible for federal funding for research, and by mid-December, 40 such lines had been approved. Obama has also appointed top scientists to key positions, including physicist Steven Chu as Secretary of Energy (see page 978), physicist and climate expert John Holdren as science adviser and marine ecologist Jane Lubchenco as administrator of the National Oceanic and Atmospheric Administration.
CONTINUED ON newsbbc4
[naturenews]
Published online 23 December 2009 | Nature | doi:10.1038/news.2009.1160
News
Fossil evidence of early reptiles' last meal
Insect remains found in the mouths of early vertebrate fossils.
Janelle Weaver
{{The jaws of two fossils may be harbouring evidence that early reptiles fed on insects.}
Biology Letters}
In the caves of a hilly Oklahoma ghost town, researchers have found what may be the first evidence of preserved insect remains in the mouths of fossilized vertebrates. The find is compelling evidence that early reptiles, the equivalent of modern-day lizards, fed on insects.
Sean Modesto, a biologist at Cape Breton University in Nova Scotia, Canada, and his colleagues found pieces of arthropod skeleton on the teeth inside two 280-million-year-old skulls of a species of reptile they have yet to fully describe. They report the discovery in the journal Biology Letters1.
One skull contained a cuticle with five segments that seemed to be part of an antenna, and the other had a long cuticle fragment that was narrow at one end and broader at the tip. This could have been part of a rear appendage.
"It is extremely uncommon to find the remains of organisms in the mouths of fossilized predators," says Matthew Vickaryous, who studies the anatomy of fossil vertebrates at the University of Guelph in Ontario, Canada. "To the best of my knowledge, this is a one of a kind find."
Lucky find
Modesto and his collaborators made this discovery entirely by chance. "You don't expect to see the last meal lodged in the teeth of fossils," Modesto says. "The modern equivalent is finding a popcorn kernel shell in the tooth of an ancient Mayan."
The two skulls come from an enigmatic group called parareptiles, which first appeared nearly 300 million years ago and for the most part became extinct by the end of the Permian period, with just a few species lingering into the age of dinosaurs.
{{What seem to be remains of an antenna and a rear appendage of insects have been found on the fossils' teeth.}
Biology Letters}
"To have pieces of both vertebrate and invertebrate preserved at the same time is very unusual," Vickaryous says. Vertebrate palaeontologists may overlook small pieces of invertebrate remains when excavating spectacular vertebrate fossils. Beyond the initial detection, preserving the remains requires careful recovery and preparation, he adds.
In younger specimens, researchers have found mollusc shell fragments in the gut of a fossil sea turtle2, preserved fish remains in a bird's stomach3, lizard and mammal skeletons in fossil dinosaur stomachs4 and dinosaur remains in a fossil mammal's stomach5. In fossil reptiles from the Permian, scientists have found plant material in the gut6 and reptile bones in the mouth7.
But little other evidence is available for the dietary habits of the vertebrates that lived during the Permian, says Conrad Labandeira, palaeoecologist at the National Museum of Natural History in Washington DC. "This paper may be more important in the long run than the original description of the fossil bones."
Insectivorous evidence
Roy Beckemeyer, palaeoentomologist at the University of Kansas Natural History Museum in Lawrence, has studied Permian insect fossils in Oklahoma. He evaluated photographs of the finds and verified that the fragments were from an arthropod. "We know of roughly 200 species of insects in this area during that time," Beckemeyer says. "There's a very good chance that these reptiles were insectivorous."
Scientists had long suspected that early reptiles were insectivorous because of the shape of their teeth, which are sharp and curve inward, making them ideal for piercing insect skeletons and holding struggling prey in place. But that evidence is indirect because it relies on comparisons between extinct and living animals.
"It's pretty much smoking-gun type of evidence when you actually have the organism in the part of the anatomy responsible for feeding," Labandeira says. "It's very compelling evidence that closes the case."
References
1. Modesto, S. P. , Scott, D. M. & Reisz, R. R. Biol. Lett. 5, 838-840 (2009).
2. Kear, B. P. Biol. Lett. 2, 113-115 (2006).
3. Mayr, G. J. Ornithol. 145, 281-286 (2004).
4. Currie, P. J. & Chen, P.-J. Can. J. Earth Sci. 38, 1705-1727 (2001).
5. Hu, Y. , Meng, J. , Wang, Y. & Li, C. Nature 433, 149-152 (2005).
6. Karlsruhe, W. M. & Sues, H.-D. Paläontol. Zeitschr. 67, 169-176 (1993).
7. Eaton, T. H. Jr American Museum Novitates No. 2169 (1964).
[naturenews]
Published online 23 December 2009 | Nature 462, 962-963 (2009) | doi:10.1038/462962a
News
News 2009
The year in which …
Lizzie Buchen
H1N1 swept the planet
The first influenza pandemic in 40 years propelled the globe onto a roller coaster of panic and complacency. In March, a new H1N1 virus — a mongrel containing genes from swine, bird and human flu viruses — emerged in North America and spread rapidly, sparking fears of a severe pandemic. The new virus was particularly dangerous for younger adults and those with underlying diseases, but most patients had mild symptoms. The low severity cut the world some slack, as a vaccine took months to produce and some manufacturers fell behind schedule; the United States, Australia and Europe didn't start vaccination programmes until October, and poorer nations months after that, if at all. As of mid-December the flu was continuing to intensify across central and eastern Europe and parts of Asia, but its second wave had peaked in North America and parts of Europe. More than 10,580 people have died.
The LHC broke a world record
The high-energy physics crown has passed from the United States to Europe. On 30 November the Large Hadron Collider (LHC) near Geneva, Switzerland, became the highest-energy accelerator in the world, breaking the record long held by the Tevatron at Fermilab in Batavia, Illinois. Europe's proton-pummelling behemoth had spent most of the year in recovery after an electrical failure during its first run in September 2008 caused massive damage. By December 2009, head-on collisions at the LHC had reached 2.36 teraelectronvolts; physicists plan to begin science at this energy level in 2010, with the hope of finding evidence of the long-sought Higgs boson and dark matter.
Climate e-mails were hacked
In what climate-change sceptics are calling the scandal of the decade — and many climate scientists are calling a meaningless nuisance — more than 1,000 e-mails between top researchers were hacked from the Climatic Research Unit (CRU) at the University of East Anglia, UK, just weeks before the Copenhagen climate summit began. Some of the e-mails revealed frustration with data and a cavalier attitude towards sceptics, but they did not discredit the solid body of evidence showing that the world is getting warmer, probably at the hands of humans. The e-mails did, however, embolden sceptics, who interpreted them as evidence of a global conspiracy. CRU director Phil Jones, who composed most of the more controversial e-mails, has stepped aside while an independent panel investigates.
The Moon was found to be damp
A decades-long debate has been resolved: water ice can accumulate in frigid craters on the Moon. On 9 October the rocket booster of NASA's Lunar Crater Observation and Sensing Satellite (LCROSS) slammed into a lunar crater that receives no sunlight, kicking up a plume of dust that was disappointing to spectators but exciting for scientists. Just before LCROSS crashed, its instruments detected water in the dust, suggesting that vapour had frozen into the crater floor. Other spectra hinted at other molecules, such as carbon dioxide, mercury and methane. Researchers hope to explore the ice for clues about the Solar System's history.
Obama boosted US science
"We will restore science to its rightful place," said US President Barack Obama in his inaugural address in January. On 9 March, Obama signed a memo supporting scientific integrity in federal decision-making and an executive order lifting the prior administration's limits on human embryonic stem-cell research. The latter move greatly expanded the number of cell lines eligible for federal funding for research, and by mid-December, 40 such lines had been approved. Obama has also appointed top scientists to key positions, including physicist Steven Chu as Secretary of Energy (see page 978), physicist and climate expert John Holdren as science adviser and marine ecologist Jane Lubchenco as administrator of the National Oceanic and Atmospheric Administration.
CONTINUED ON newsbbc4
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