Ancient Animals (New scientific discoveries)
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star_munir
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Ancient Animals (New scientific discoveries)
Biggest dinosaurs were in Antarctica
Washington, December 11: Researchers have discovered a new genus and species of dinosaur in Antarctica, which they say belongs to the Early Jurassic period.
They call this massive plant-eating primitive sauropodomorph Glacialisaurus hammeri, who lived about 190 million years ago.
The determination of the new dinosaur find is based on partial foot, leg and ankle bones found on Mt. Kirkpatrick near the Beardmore Glacier in Antarctica at an elevation of more than 13,000 feet.
“The fossils were painstakingly removed from the ice and rock using jackhammers, rock saws and chisels under extremely difficult conditions over the course of two field seasons,” said Nathan Smith, a graduate student at The Field Museum.
“They are important because they help to establish that primitive sauropodomorph dinosaurs were more broadly distributed than previously thought, and that they coexisted with their cousins, the true sauropods,” he added.
A report about the find, published in the Acta Palaeontologica Poloncica, suggests that sauropodomorph dinosaurs were the largest animals to ever walk the earth.
The report further states that they were long-necked herbivores and included Diplodocus and Apatosaurus. Their sister group is the theropods, which include Tyrannosaurus, Velociraptor, and modern birds.
Glacialisaurus hammeri, named after Professor William Hammer of Augustana College who led the two field trips to Antarctica that uncovered the fossils, was about 20 to 25 feet long and weighed about four to six tons.
Glacialisaurus belongs to the sauropodomorph family Massopsondylidae, which may represent a secondary radiation of basal sauropodomorphs during the Early Jurassic.
The new discovery, according to the report, shows that sauropodomorphs were widely distributed in the Early Jurassic. It also shows that these dinosaurs not only existed in China, South Africa, South America and North America but in Antarctica also.
“This was probably due to the fact that major connections between the continents still existed at that time, and because climates were more equitable across latitudes than they are today,” Smith said.
Bureau Report
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star_munir
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Ancient sea scorpion was bigger than man
London, Nov 22: Scientists have found the fossilised claw of a 2.5-metre (8-foot) sea scorpion, a nightmarish creature living before the age of dinosaurs.
The discovery of the 390-million-year-old specimen in a German quarry suggests prehistoric spiders, insects and crabs were much larger than previously thought, researchers at Britain's Bristol University said on early Thursday.
"This is an amazing discovery," said university researcher Simon Braddy.
"We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches, and jumbo dragonflies but we never realised, until now, just how big some of these ancient creepy-crawlies were."
The find was described by Braddy and colleagues in the journal Biology Letters.
The claw of the sea scorpion Jaekelopterus rhenaniae measured 46 centimetres (18 inches) long, indicating the creature was half a metre longer than previous estimates of the ancient arthropods.
Just why prehistoric arthropods -- creatures with external skeletons and segmented bodies -- grew so large is unclear. Some scientists believe they may have become giants because of the higher levels of oxygen in the atmosphere in the past.
Another theory is that they evolved in an "arms race" alongside their likely prey, the early armoured fish.
Bureau Report
London, Nov 22: Scientists have found the fossilised claw of a 2.5-metre (8-foot) sea scorpion, a nightmarish creature living before the age of dinosaurs.
The discovery of the 390-million-year-old specimen in a German quarry suggests prehistoric spiders, insects and crabs were much larger than previously thought, researchers at Britain's Bristol University said on early Thursday.
"This is an amazing discovery," said university researcher Simon Braddy.
"We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches, and jumbo dragonflies but we never realised, until now, just how big some of these ancient creepy-crawlies were."
The find was described by Braddy and colleagues in the journal Biology Letters.
The claw of the sea scorpion Jaekelopterus rhenaniae measured 46 centimetres (18 inches) long, indicating the creature was half a metre longer than previous estimates of the ancient arthropods.
Just why prehistoric arthropods -- creatures with external skeletons and segmented bodies -- grew so large is unclear. Some scientists believe they may have become giants because of the higher levels of oxygen in the atmosphere in the past.
Another theory is that they evolved in an "arms race" alongside their likely prey, the early armoured fish.
Bureau Report
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star_munir
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Oldest living tree in Sweden
Stockholm, April 18: The world`s oldest living tree on record is a nearly 10,000 year-old spruce that has been discovered in Central Sweden, Umeaa University said.
Researchers had discovered a spruce with genetic material dating back 9,550 years in the Fulu Mountain in Dalarna, according to Leif Kullmann, a professor of physical geography at the University in Northwestern Sweden.
That would mean it had taken root in roughly the year 7,542 BC.
"It was a big surprise because we thought until (now) that this kind of spruce grew much later in those regions," he said.
Scientists had previously believed the world`s oldest trees were 4,000 to 5,000 year-old pine trees found in North America.
The new record-breaking tree was discovered in Dalarna in 2004 when Swedish researchers were carrying out a census of tree species in the region, Kullman said.
The tree`s genetic material age had been calculated using carbon dating at a laboratory in Miami, Florida.
Spruces, which according to Kullmann offer rich insight into climate change, had long been regarded as relatively newcomers in the Swedish mountain region.
The discovery of the ancient tree had therefore led to "a big change in our way of thinking," he said.
Bureau Report
Stockholm, April 18: The world`s oldest living tree on record is a nearly 10,000 year-old spruce that has been discovered in Central Sweden, Umeaa University said.
Researchers had discovered a spruce with genetic material dating back 9,550 years in the Fulu Mountain in Dalarna, according to Leif Kullmann, a professor of physical geography at the University in Northwestern Sweden.
That would mean it had taken root in roughly the year 7,542 BC.
"It was a big surprise because we thought until (now) that this kind of spruce grew much later in those regions," he said.
Scientists had previously believed the world`s oldest trees were 4,000 to 5,000 year-old pine trees found in North America.
The new record-breaking tree was discovered in Dalarna in 2004 when Swedish researchers were carrying out a census of tree species in the region, Kullman said.
The tree`s genetic material age had been calculated using carbon dating at a laboratory in Miami, Florida.
Spruces, which according to Kullmann offer rich insight into climate change, had long been regarded as relatively newcomers in the Swedish mountain region.
The discovery of the ancient tree had therefore led to "a big change in our way of thinking," he said.
Bureau Report
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star_munir
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Britain was a ‘Jurassic Park’
London, April 14: Britain was one of the world's original Jurassic Parks about 140 million years ago, researchers have claimed.
Researchers have identified 108 species found since the first discovery was named in 1824 and believe that the variety of creatures make Britain an important area for dinosaur remains.
"We're probably in the top five places in the world for concentrations of dinosaurs," said Darren Naish, a vertebrate paleontologist at Portsmouth university and one of the researchers who carried out the study.
"We've got large numbers of middle Jurassic and early cretaceous period species, including long-necked dinosaurs and predators such as spinosaurs and velociraptors."
The review, which has taken three years and is published in the journal of the geological society, documents every known species and genus of dinosaur known to have lived in Britain from 200 million to 65 million years ago.
The scientists admit that the number of species found may partly be explained by the long-standing popularity of dinosaur fossil hunting.
"People in Britain have been finding dinosaur fossils for longer than anywhere else but we have an exceptionally large number here," Naish said.
In the years since 1819, experts have excavated everything from jaw bones to dinosaur egg shells at sites ranging from the Scottish highlands and islands to the south coast of England. The most productive areas include Oxfordshire, the southern coast of the Isle of Wight, Dorset and the shore near Bristol.
The most complete remains include a scelidosaurus found in 1860 in the black ven cliffs near Lyme Regis, Dorset, on what has come to be known as the "Jurassic Coast".
According to the report, Britain's indigenous species include stegosaurus, which had distinctive armour plates, as well as predatory theropods and vegetarian sauropods.
Mike Benton, professor of vertebrate palacontology at Bristol University, was cautious about singling out Britain as an exceptional dinosaur location. "The UK has produced the oldest fossils of a few dinosaur groups. But who knows what might come out of China or Africa in the next decades?"
London, April 14: Britain was one of the world's original Jurassic Parks about 140 million years ago, researchers have claimed.
Researchers have identified 108 species found since the first discovery was named in 1824 and believe that the variety of creatures make Britain an important area for dinosaur remains.
"We're probably in the top five places in the world for concentrations of dinosaurs," said Darren Naish, a vertebrate paleontologist at Portsmouth university and one of the researchers who carried out the study.
"We've got large numbers of middle Jurassic and early cretaceous period species, including long-necked dinosaurs and predators such as spinosaurs and velociraptors."
The review, which has taken three years and is published in the journal of the geological society, documents every known species and genus of dinosaur known to have lived in Britain from 200 million to 65 million years ago.
The scientists admit that the number of species found may partly be explained by the long-standing popularity of dinosaur fossil hunting.
"People in Britain have been finding dinosaur fossils for longer than anywhere else but we have an exceptionally large number here," Naish said.
In the years since 1819, experts have excavated everything from jaw bones to dinosaur egg shells at sites ranging from the Scottish highlands and islands to the south coast of England. The most productive areas include Oxfordshire, the southern coast of the Isle of Wight, Dorset and the shore near Bristol.
The most complete remains include a scelidosaurus found in 1860 in the black ven cliffs near Lyme Regis, Dorset, on what has come to be known as the "Jurassic Coast".
According to the report, Britain's indigenous species include stegosaurus, which had distinctive armour plates, as well as predatory theropods and vegetarian sauropods.
Mike Benton, professor of vertebrate palacontology at Bristol University, was cautious about singling out Britain as an exceptional dinosaur location. "The UK has produced the oldest fossils of a few dinosaur groups. But who knows what might come out of China or Africa in the next decades?"
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star_munir
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Meteorite that killed dinosaurs
Washington, April 14: The meteorite linked to the mass extinction of dinosaurs and other life forms 65 million years ago was four to six kilometres in diameter.
That's the conclusion of a team of Hawaii University researchers who have evolved a mechanism to measure the size of meteorites that have rammed into earth over millennia.
Francois Paquay and his team used isotopes of the rare element osmium in sediments at the bottom of the ocean to estimate the meteorite sizes and also the frequency with which they hit earth.
Paquay's team included Tarun Dalai from the Indian Institute of Technology (IIT) at Kharagpur.
Paquay analysed samples from two meteorite-hit sites and measured osmium isotope levels during the late Eocene period, a time during which large meteorite impacts are known to have occurred.
'The record in marine sediments allowed us to discover how osmium changes in the ocean during and after an impact,' said Paquay.
'The vaporization of meteorites carries a pulse of this rare element into the area where they landed,' said Rodey Batiza of the National Science Foundation (NSF), which funded the research.
'The osmium mixes throughout the ocean quickly. Records of these impact-induced changes in ocean chemistry are then preserved in deep-sea sediments,' he added. Under the assumption that all the osmium carried by meteorites is dissolved in seawater, the geologists were able to use their method to estimate the K-T meteorite that wiped out the dinosaurs was four to six kilometres in diameter.
The scientists expect that this new approach to estimating impact size will become an important complement to a better-known method based on iridium.
Paquay, Dalai and other researchers have published their findings in the latest issue of the journal Science.
Washington, April 14: The meteorite linked to the mass extinction of dinosaurs and other life forms 65 million years ago was four to six kilometres in diameter.
That's the conclusion of a team of Hawaii University researchers who have evolved a mechanism to measure the size of meteorites that have rammed into earth over millennia.
Francois Paquay and his team used isotopes of the rare element osmium in sediments at the bottom of the ocean to estimate the meteorite sizes and also the frequency with which they hit earth.
Paquay's team included Tarun Dalai from the Indian Institute of Technology (IIT) at Kharagpur.
Paquay analysed samples from two meteorite-hit sites and measured osmium isotope levels during the late Eocene period, a time during which large meteorite impacts are known to have occurred.
'The record in marine sediments allowed us to discover how osmium changes in the ocean during and after an impact,' said Paquay.
'The vaporization of meteorites carries a pulse of this rare element into the area where they landed,' said Rodey Batiza of the National Science Foundation (NSF), which funded the research.
'The osmium mixes throughout the ocean quickly. Records of these impact-induced changes in ocean chemistry are then preserved in deep-sea sediments,' he added. Under the assumption that all the osmium carried by meteorites is dissolved in seawater, the geologists were able to use their method to estimate the K-T meteorite that wiped out the dinosaurs was four to six kilometres in diameter.
The scientists expect that this new approach to estimating impact size will become an important complement to a better-known method based on iridium.
Paquay, Dalai and other researchers have published their findings in the latest issue of the journal Science.
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star_munir
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Earth`s 1st animal was complex
New York, April 12: The first animal on Earth, a mysterious creature whose characteristics can only be inferred from fossils, was probably more complex than earlier thought, a new study has revealed.
Using high-powered technologies, researchers in the United States have defined the earliest splits at the base of the animal tree of life - a hierarchical representation of the evolutionary relationships between species, introduced by Charles Darwin.
According to the study, the comb jelly split off from other animals and diverged onto its own evolutionary path before the sponge, a finding that challenges the traditional view of the base of the tree of life. The comb jelly had achieved seniority over simpler sponge.
"This was a complete shocker. So shocking that we initially thought something had gone very wrong. The presence of the relatively complex comb jelly at the base of the tree of life suggests that the first animal was probably more complex than believed," lead researcher Casey Dunn said.
Bureau Report
New York, April 12: The first animal on Earth, a mysterious creature whose characteristics can only be inferred from fossils, was probably more complex than earlier thought, a new study has revealed.
Using high-powered technologies, researchers in the United States have defined the earliest splits at the base of the animal tree of life - a hierarchical representation of the evolutionary relationships between species, introduced by Charles Darwin.
According to the study, the comb jelly split off from other animals and diverged onto its own evolutionary path before the sponge, a finding that challenges the traditional view of the base of the tree of life. The comb jelly had achieved seniority over simpler sponge.
"This was a complete shocker. So shocking that we initially thought something had gone very wrong. The presence of the relatively complex comb jelly at the base of the tree of life suggests that the first animal was probably more complex than believed," lead researcher Casey Dunn said.
Bureau Report
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star_munir
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Was early elephant an amphibian?
Washington, April 22: Scientists studying two very ancient elephants surmised that they were probably semi-aquatic mammals, eating freshwater plants.
“Molecular data from modern elephants share a common ancestry with the sirenians - aquatic sea cows and dugongs,” said Alexander Liu of Oxford University, co-author of the report.
“Elephants may have an ancestor which was amphibious in its mode of life and we wanted to know if Moeritherium or Barytherium (existing 37 million years ago) was this semi-aquatic ancient relative.”
“Unfortunately only fragments of the skeletons of these early elephants survive, so instead of looking at their bones we looked at the chemical composition of their teeth to determine what they ate and how they lived,” he added.
Alex Liu, with colleagues Erik Seiffert from Stony Brook University (US) and Elwyn Simons from the Duke Lemur Center (US), analysed the oxygen and carbon isotope ratios within tooth enamel from both extinct species.
While carbon isotopes can give clues as to an animal’s diet, oxygen isotopes found in teeth come from local water sources - and variations in the ratios of these isotopes can indicate the type of environment the animal lived in.
They compared the ratios of these isotopes to terrestrial animals from the same period and these results - when combined with results from studies of embryology, molecular data, and sedimentology - lead them to believe that Moeritherium was semi-aquatic.
Liu said: “We now have substantial evidence to suggest that modern elephants do have ancient relatives which lived primarily in water.”
These findings were published online in PNAS.
Bureau Report
Washington, April 22: Scientists studying two very ancient elephants surmised that they were probably semi-aquatic mammals, eating freshwater plants.
“Molecular data from modern elephants share a common ancestry with the sirenians - aquatic sea cows and dugongs,” said Alexander Liu of Oxford University, co-author of the report.
“Elephants may have an ancestor which was amphibious in its mode of life and we wanted to know if Moeritherium or Barytherium (existing 37 million years ago) was this semi-aquatic ancient relative.”
“Unfortunately only fragments of the skeletons of these early elephants survive, so instead of looking at their bones we looked at the chemical composition of their teeth to determine what they ate and how they lived,” he added.
Alex Liu, with colleagues Erik Seiffert from Stony Brook University (US) and Elwyn Simons from the Duke Lemur Center (US), analysed the oxygen and carbon isotope ratios within tooth enamel from both extinct species.
While carbon isotopes can give clues as to an animal’s diet, oxygen isotopes found in teeth come from local water sources - and variations in the ratios of these isotopes can indicate the type of environment the animal lived in.
They compared the ratios of these isotopes to terrestrial animals from the same period and these results - when combined with results from studies of embryology, molecular data, and sedimentology - lead them to believe that Moeritherium was semi-aquatic.
Liu said: “We now have substantial evidence to suggest that modern elephants do have ancient relatives which lived primarily in water.”
These findings were published online in PNAS.
Bureau Report
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NAZIM.KHERANI
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star_munir wrote: Oldest living tree in Sweden
Stockholm, April 18: The world`s oldest living tree on record is a nearly 10,000 year-old spruce that has been discovered in Central Sweden, Umeaa University said.
Researchers had discovered a spruce with genetic material dating back 9,550 years in the Fulu Mountain in Dalarna, according to Leif Kullmann, a professor of physical geography at the University in Northwestern Sweden.
That would mean it had taken root in roughly the year 7,542 BC.
"It was a big surprise because we thought until (now) that this kind of spruce grew much later in those regions," he said.
Scientists had previously believed the world`s oldest trees were 4,000 to 5,000 year-old pine trees found in North America.
The new record-breaking tree was discovered in Dalarna in 2004 when Swedish researchers were carrying out a census of tree species in the region, Kullman said.
The tree`s genetic material age had been calculated using carbon dating at a laboratory in Miami, Florida.
Spruces, which according to Kullmann offer rich insight into climate change, had long been regarded as relatively newcomers in the Swedish mountain region.
The discovery of the ancient tree had therefore led to "a big change in our way of thinking," he said.
Bureau Report