The smallest animal with a backbone known to science, a fish from the carp family, has been discovered in the peat swamps of Indonesia.
Mature females of the fish species Paedocypris progenetica reach just 7.9mm (3/10 in) in length, making them the smallest vertebrates yet identified by a tenth of a millimetre.
The previous size record for a vertebrate was held by the Indo-Pacific goby, another fish, at 8mm. Britain's smallest fish, and vertebrate, is the marine Guillet's goby, Lebetus guilleti, which measures 24mm.
The species was discovered in the highly acidic peat swamps of the Indonesian island of Sumatra by a team led by Ralf Britz, a zoologist at the Natural History Museum in London.
"This is one of the strangest fish that I've seen in my whole career," Dr Britz said.
"It's tiny, it lives in acid and it has these bizarre grasping fins. I hope that we'll have time to find out more about them before their habitat disappears completely."
The species is transparent and lives in dark tea-coloured swamp waters, which at pH3 are 100 times more acidic than rainwater. Although these swamps were once thought to harbour very few animals, recent research has shown that they are home to a highly diverse range of species that occur nowhere else.
The peat swamps were damaged by forest fires in 1997, and are also threatened by logging, urbanisation and agriculture. The scientists behind the discovery said that several populations of P. progenetica had already been lost.
"Many of the peat swamps we surveyed throughout South-East Asia no longer exist and their fauna is eradicated," Dr Britz said. "Populations of all the highly endemic miniature fishes of peat swamps have decreased or collapsed."
Details of the discovery are published today in the journal Proceedings of the Royal Society of London, Series B. The male fish grow to 8.6mm, and boast enlarged pelvic fins with exceptionally large muscles relative to the size of the rest of their bodies. The researchers believe that these may be used for grasping females during sex. The females are smaller still, reaching 7.9mm.
The smallest known mammal is Kitti's hog-nosed bat, Craseonycteris thonglongyai, from western Thailand, which measures between 2.9cm and 3.3cm long.
Friday, November 28, 2008
Tuesday, November 25, 2008
Study: T. Rex No Speedster
Tyrannosaurus rex, the mighty predator that lived about 85 million years ago, was probably just a plodder and not the quick-footed killer depicted in Hollywood blockbusters, scientists said on Wednesday. Far from chasing its prey at speeds of up to 45 mph, as some studies have suggested, the fearsome creatures may not have been able to run at all.
"These animals were no speed demons," John Hutchinson, of Stanford University in California, said in an interview.
The biologist who specializes in the evolution of movement said the science of how animals move shows that big creatures do not go fast. At about 40 feet long, up to 20 feet tall and weighing about 13,000 pounds, Tyrannosaurus rex was very big.
Hutchinson and Mariano Garcia, of Borg-Warner Automotive in Ithaca, New York, created a computer program to analyze animal motion and determine how fast large dinosaurs could move. Writing in the science journal Nature, they calculated that two-legged T. rex would have needed impossibly massive leg muscles to generate enough force to support its huge body at a very fast running pace.
"It has been known for a long time that as things get bigger, they don't move as fast relative to their size and in fact as they get really, really big, they can't run at all," said Garcia. "But until now, no one that I know of has tried to predict the cutoffs, which is what we are doing."
Because dinosaurs are extinct the scientists had very little to go on. Fossils of smaller dinosaurs indicate that they moved fast but there is no similar evidence for their bigger cousins. Hutchinson and Garcia incorporated the impact of posture, center of mass, leg weight, total weight and torque, the twisting force that muscles need to apply about the joints, into their program. They tested its accuracy by using data from living animals.
When they tested the model on a T. rex running about 45 mph their calculations showed it would have needed 43 percent of its body weight in each leg as supportive muscle.
"Our model shows that these really fast speeds of 50 mph and probably down to even 25 mph just don't hold up when you really scrutinize them and look at the physics," Hutchinson explained. "It doesn't make a lot of sense that these animals could go that fast. There's really no good evidence that they could."
To prove their point they scaled up a chicken to the size of T. rex and found the giant chicken probably would not have been able to stand.
"These animals were no speed demons," John Hutchinson, of Stanford University in California, said in an interview.
The biologist who specializes in the evolution of movement said the science of how animals move shows that big creatures do not go fast. At about 40 feet long, up to 20 feet tall and weighing about 13,000 pounds, Tyrannosaurus rex was very big.
Hutchinson and Mariano Garcia, of Borg-Warner Automotive in Ithaca, New York, created a computer program to analyze animal motion and determine how fast large dinosaurs could move. Writing in the science journal Nature, they calculated that two-legged T. rex would have needed impossibly massive leg muscles to generate enough force to support its huge body at a very fast running pace.
"It has been known for a long time that as things get bigger, they don't move as fast relative to their size and in fact as they get really, really big, they can't run at all," said Garcia. "But until now, no one that I know of has tried to predict the cutoffs, which is what we are doing."
Because dinosaurs are extinct the scientists had very little to go on. Fossils of smaller dinosaurs indicate that they moved fast but there is no similar evidence for their bigger cousins. Hutchinson and Garcia incorporated the impact of posture, center of mass, leg weight, total weight and torque, the twisting force that muscles need to apply about the joints, into their program. They tested its accuracy by using data from living animals.
When they tested the model on a T. rex running about 45 mph their calculations showed it would have needed 43 percent of its body weight in each leg as supportive muscle.
"Our model shows that these really fast speeds of 50 mph and probably down to even 25 mph just don't hold up when you really scrutinize them and look at the physics," Hutchinson explained. "It doesn't make a lot of sense that these animals could go that fast. There's really no good evidence that they could."
To prove their point they scaled up a chicken to the size of T. rex and found the giant chicken probably would not have been able to stand.
Friday, November 21, 2008
Poison, Nets Don’t Slow Non-Native Fish
SACRAMENTO, Calif. Jan. 13 - The fish are definitely winning the battle, despite being poisoned, shocked, netted, hooked, and most recently blown up with detonation cord.
Nothing state wildlife officials have tried has eradicated non-native northern pike from Lake Davis, where they were dumped sometime before 1994. Officials fear the voracious pike could further threaten the state's salmon population should they escape downstream from the northern Sierra Nevada lake.
The state has devoted full-time crews to catching predatory pike each of the last three years, only to see the population skyrocket. They caught 601 pike in 2000, 6,358 in 2001, and 17,635 by the time they put away their nets and electric prods last month.
"I can't say it was unexpected," said Steve Martarano, a spokesman for the California Department of Fish and Game. While there are more pike in the lake, he said, "we've gotten a lot better at knowing where the pike are."
Virtually all were less than a foot long and under a year old, too small to eat the larger trout in the lake.More than 50,000 catchable trout were dumped into the lake last year, with more stocking planned this year. That's kept drawing the anglers important to the area's tourist industry, officials say.。
But the pike are maturing quickly, fisheries experts found, estimating that fish hatched in 2001 may produce a generation nine to 14 times larger than their own."Those things spawn like crazy," Martarano said.
Department officials and residents start planning their next move at a public hearing Monday.That may include another attempt to partially drain and poison the lake, as the state tried in 1997. The pike survived, but the tactic poisoned the department's relationship with the community and cost the state $2 million, plus $9.2 million in reparations to residents.Now state officials say they won't act without community support.
Once the ice clears in late March or early April, they plan to blow up 10 acres at a time over the next two years, concentrating on shallow areas where baby pike grow into big toothy pike. Pressure from the underwater explosions is expected to kill nearby fish and amphibians of all kinds.
Nothing state wildlife officials have tried has eradicated non-native northern pike from Lake Davis, where they were dumped sometime before 1994. Officials fear the voracious pike could further threaten the state's salmon population should they escape downstream from the northern Sierra Nevada lake.
The state has devoted full-time crews to catching predatory pike each of the last three years, only to see the population skyrocket. They caught 601 pike in 2000, 6,358 in 2001, and 17,635 by the time they put away their nets and electric prods last month.
"I can't say it was unexpected," said Steve Martarano, a spokesman for the California Department of Fish and Game. While there are more pike in the lake, he said, "we've gotten a lot better at knowing where the pike are."
Virtually all were less than a foot long and under a year old, too small to eat the larger trout in the lake.More than 50,000 catchable trout were dumped into the lake last year, with more stocking planned this year. That's kept drawing the anglers important to the area's tourist industry, officials say.。
But the pike are maturing quickly, fisheries experts found, estimating that fish hatched in 2001 may produce a generation nine to 14 times larger than their own."Those things spawn like crazy," Martarano said.
Department officials and residents start planning their next move at a public hearing Monday.That may include another attempt to partially drain and poison the lake, as the state tried in 1997. The pike survived, but the tactic poisoned the department's relationship with the community and cost the state $2 million, plus $9.2 million in reparations to residents.Now state officials say they won't act without community support.
Once the ice clears in late March or early April, they plan to blow up 10 acres at a time over the next two years, concentrating on shallow areas where baby pike grow into big toothy pike. Pressure from the underwater explosions is expected to kill nearby fish and amphibians of all kinds.
Monday, November 17, 2008
Teacher Ants Show Students the Way to Food
Ants have a myriad of complex social behaviors despite possessing only teeny brains. Now new research suggests that teaching should be added to the list of ant accomplishments.
Nigel Franks and Tom Richardson of the University of Bristol in England studied so-called tandem running in Temnothorax albipennis ants, during which two ants run a course between nest and food with various stops and starts en route. The researchers found that the lead ant who knows the way to the food slows down as the follower familiarizes itself with the route and will not proceed until the follower taps it on the back. The two also maintain a variable but matching speed and distance over time.
"This behavior is beautifully simple," Richardson says. "If one experimentally removes the follower and taps the leader with a hair at a rate of two times per second or more, the leader will continue."
Biologists have a definition of a teacher in the world of animals: any individual who sacrifices some potential gain in order to educate a naïve counterpart. In a report published today in Nature Franks and Richardson argue that true teaching also requires feedback between the teacher and the student. The ant duos qualify on both counts. "The teacher provides information or guidance to the pupil at a rate suited to the pupil's abilities and the pupil signals to the teacher when parts of the 'lesson' have been assimilated and that the lesson may continue," Franks notes. "True teaching always involves feedback in both directions."
In the case of the ants, the teachers sacrificed their own speed, as evidenced by the observation that they reached the food source four times more quickly on their own than when they had a student in tow. But the students found food more than a minute faster with the help of teaching and then often themselves became teachers for other ants. Sometimes, however, knowledge of a food source needs to be communicated faster than one-on-one training can accomplish. In those situations, large ant groups often broadcast such information through pheromone trails or other means. But tandem running proves that teaching may develop even in organisms that lack large brains, providing help for pupils with the tiniest of intellects. --David Biello
Nigel Franks and Tom Richardson of the University of Bristol in England studied so-called tandem running in Temnothorax albipennis ants, during which two ants run a course between nest and food with various stops and starts en route. The researchers found that the lead ant who knows the way to the food slows down as the follower familiarizes itself with the route and will not proceed until the follower taps it on the back. The two also maintain a variable but matching speed and distance over time.
"This behavior is beautifully simple," Richardson says. "If one experimentally removes the follower and taps the leader with a hair at a rate of two times per second or more, the leader will continue."
Biologists have a definition of a teacher in the world of animals: any individual who sacrifices some potential gain in order to educate a naïve counterpart. In a report published today in Nature Franks and Richardson argue that true teaching also requires feedback between the teacher and the student. The ant duos qualify on both counts. "The teacher provides information or guidance to the pupil at a rate suited to the pupil's abilities and the pupil signals to the teacher when parts of the 'lesson' have been assimilated and that the lesson may continue," Franks notes. "True teaching always involves feedback in both directions."
In the case of the ants, the teachers sacrificed their own speed, as evidenced by the observation that they reached the food source four times more quickly on their own than when they had a student in tow. But the students found food more than a minute faster with the help of teaching and then often themselves became teachers for other ants. Sometimes, however, knowledge of a food source needs to be communicated faster than one-on-one training can accomplish. In those situations, large ant groups often broadcast such information through pheromone trails or other means. But tandem running proves that teaching may develop even in organisms that lack large brains, providing help for pupils with the tiniest of intellects. --David Biello
Friday, November 14, 2008
Take Your Pet to See Santa Claus!
Delivering toys around the globe overnight has got to be easier than getting four dogs to sit still for a photograph.
Ernest Leverette Sr. was nevertheless willing to give it a shot.
Leverette, dressed in full Santa Claus regalia, endured lashing tails and doggy kisses to pose for pictures with pets and raise money for the Pender County Humane Society.
For Leverette, it's a much better job than his career as a truck driver.
Humane society treasurer April Farr said the money will be a big help in paying the $2,500 weekly cost of operating the organization.
Leverette and photographer Dick Parrot managed to choreograph a moment's stillness by Emma Jean the basset hound, Oscar the Yorkshire terrier, Doogie the poodle and Clementine the English bulldog for the Kivlighan family.
Another pair were a bit more challenging. Patch quietly rested his forelegs on the arm of Santa's chair, but Alyssa Savonen's other dog, Annabelle, couldn't resist licking Leverette's face until Savonen warned her, "Do you want a spanking? Stop it!"
Pets Plus manager Moore said increasingly people are adding beds, toys and treats for their pets to their holiday shopping lists.
Moore herself is a supporter of animal charities. She adopted her dog Ripple last year from the Southport-Oak Island Animal Rescue.
Ernest Leverette Sr. was nevertheless willing to give it a shot.
Leverette, dressed in full Santa Claus regalia, endured lashing tails and doggy kisses to pose for pictures with pets and raise money for the Pender County Humane Society.
For Leverette, it's a much better job than his career as a truck driver.
Humane society treasurer April Farr said the money will be a big help in paying the $2,500 weekly cost of operating the organization.
Leverette and photographer Dick Parrot managed to choreograph a moment's stillness by Emma Jean the basset hound, Oscar the Yorkshire terrier, Doogie the poodle and Clementine the English bulldog for the Kivlighan family.
Another pair were a bit more challenging. Patch quietly rested his forelegs on the arm of Santa's chair, but Alyssa Savonen's other dog, Annabelle, couldn't resist licking Leverette's face until Savonen warned her, "Do you want a spanking? Stop it!"
Pets Plus manager Moore said increasingly people are adding beds, toys and treats for their pets to their holiday shopping lists.
Moore herself is a supporter of animal charities. She adopted her dog Ripple last year from the Southport-Oak Island Animal Rescue.
Thursday, November 6, 2008
Striped Surprise--British Shetland Pony Gives Birth to Zebra
The owners of Tilly the Shetland pony received a double shock when she gave birth. They didn't know she was pregnant - and they certainly weren't expecting a zebra.
Tilly's owners at Eden Ostrich World, a modest visitor attraction on a farm near Penrith in northwestern England, had been unaware of the pony's exotic past life at a wildlife park, where she shared a field with a male zebra.
"She was fairly fat when we received her and we thought that she was getting fatter," Ostrich World manager Karen Peet said.
"It really was a bit of a shock when we got up one morning and we saw the foal that was there."
The striped half-Shetland, half-zebra foal - dubbed a "zetland" or a "shebra" but as yet unnamed - has flourished since her birth a week ago, and Peet said visitors would be able to view her beginning Monday.
The farm plans to hold a competition to name the creature, which has black-and-tan stripes and a zebra's distinctive large head.
Veterinarians say such a foal is rare, but not unknown. British zoos have reported the birth of several "zeedonks" - offspring of a zebra and a donkey - over the years.
"Ponies and zebras very rarely share the same environment even in the wild. A meeting between the two is very rare in the natural environment," said Lesley Barwise-Munro, spokeswoman for the British Equine Veterinary Association.
"If the zebra is the father and the horse is the mother there is no reason why a normal fertilization and a pregnancy should not take place," she added. "But the offspring is unlikely to be fertile."
Tilly's owners at Eden Ostrich World, a modest visitor attraction on a farm near Penrith in northwestern England, had been unaware of the pony's exotic past life at a wildlife park, where she shared a field with a male zebra.
"She was fairly fat when we received her and we thought that she was getting fatter," Ostrich World manager Karen Peet said.
"It really was a bit of a shock when we got up one morning and we saw the foal that was there."
The striped half-Shetland, half-zebra foal - dubbed a "zetland" or a "shebra" but as yet unnamed - has flourished since her birth a week ago, and Peet said visitors would be able to view her beginning Monday.
The farm plans to hold a competition to name the creature, which has black-and-tan stripes and a zebra's distinctive large head.
Veterinarians say such a foal is rare, but not unknown. British zoos have reported the birth of several "zeedonks" - offspring of a zebra and a donkey - over the years.
"Ponies and zebras very rarely share the same environment even in the wild. A meeting between the two is very rare in the natural environment," said Lesley Barwise-Munro, spokeswoman for the British Equine Veterinary Association.
"If the zebra is the father and the horse is the mother there is no reason why a normal fertilization and a pregnancy should not take place," she added. "But the offspring is unlikely to be fertile."
Monday, November 3, 2008
Scientists Find World's Tiniest Vertebrate
The smallest animal with a backbone known to science, a fish from the carp family, has been discovered in the peat swamps of Indonesia.
Mature females of the fish species Paedocypris progenetica reach just 7.9mm (3/10 in) in length, making them the smallest vertebrates yet identified by a tenth of a millimetre.
The previous size record for a vertebrate was held by the Indo-Pacific goby, another fish, at 8mm. Britain's smallest fish, and vertebrate, is the marine Guillet's goby, Lebetus guilleti, which measures 24mm.
The species was discovered in the highly acidic peat swamps of the Indonesian island of Sumatra by a team led by Ralf Britz, a zoologist at the Natural History Museum in London.
"This is one of the strangest fish that I've seen in my whole career," Dr Britz said.
"It's tiny, it lives in acid and it has these bizarre grasping fins. I hope that we'll have time to find out more about them before their habitat disappears completely."
The species is transparent and lives in dark tea-coloured swamp waters, which at pH3 are 100 times more acidic than rainwater. Although these swamps were once thought to harbour very few animals, recent research has shown that they are home to a highly diverse range of species that occur nowhere else.
The peat swamps were damaged by forest fires in 1997, and are also threatened by logging, urbanisation and agriculture. The scientists behind the discovery said that several populations of P. progenetica had already been lost.
"Many of the peat swamps we surveyed throughout South-East Asia no longer exist and their fauna is eradicated," Dr Britz said. "Populations of all the highly endemic miniature fishes of peat swamps have decreased or collapsed."
Details of the discovery are published today in the journal Proceedings of the Royal Society of London, Series B. The male fish grow to 8.6mm, and boast enlarged pelvic fins with exceptionally large muscles relative to the size of the rest of their bodies. The researchers believe that these may be used for grasping females during sex. The females are smaller still, reaching 7.9mm.
The smallest known mammal is Kitti's hog-nosed bat, Craseonycteris thonglongyai, from western Thailand, which measures between 2.9cm and 3.3cm long.
Mature females of the fish species Paedocypris progenetica reach just 7.9mm (3/10 in) in length, making them the smallest vertebrates yet identified by a tenth of a millimetre.
The previous size record for a vertebrate was held by the Indo-Pacific goby, another fish, at 8mm. Britain's smallest fish, and vertebrate, is the marine Guillet's goby, Lebetus guilleti, which measures 24mm.
The species was discovered in the highly acidic peat swamps of the Indonesian island of Sumatra by a team led by Ralf Britz, a zoologist at the Natural History Museum in London.
"This is one of the strangest fish that I've seen in my whole career," Dr Britz said.
"It's tiny, it lives in acid and it has these bizarre grasping fins. I hope that we'll have time to find out more about them before their habitat disappears completely."
The species is transparent and lives in dark tea-coloured swamp waters, which at pH3 are 100 times more acidic than rainwater. Although these swamps were once thought to harbour very few animals, recent research has shown that they are home to a highly diverse range of species that occur nowhere else.
The peat swamps were damaged by forest fires in 1997, and are also threatened by logging, urbanisation and agriculture. The scientists behind the discovery said that several populations of P. progenetica had already been lost.
"Many of the peat swamps we surveyed throughout South-East Asia no longer exist and their fauna is eradicated," Dr Britz said. "Populations of all the highly endemic miniature fishes of peat swamps have decreased or collapsed."
Details of the discovery are published today in the journal Proceedings of the Royal Society of London, Series B. The male fish grow to 8.6mm, and boast enlarged pelvic fins with exceptionally large muscles relative to the size of the rest of their bodies. The researchers believe that these may be used for grasping females during sex. The females are smaller still, reaching 7.9mm.
The smallest known mammal is Kitti's hog-nosed bat, Craseonycteris thonglongyai, from western Thailand, which measures between 2.9cm and 3.3cm long.
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