2010年8月22日星期日
2010年8月14日星期六
Flying dinosaurs with wingspans of ten to fifteen feet (eye witnesses say they can be much larger)
Bat-like wings, a beak full of razor sharp teeth, tearing claws, a long tail with a flanged end, is this night-flying reptile a figment of the imagination? Or does it provide living proof that dinosaurs still exist today in far-flung and obscure little corners of the world. Researchers have unearthed the pterosaur, 2010.
The Ropen (Demon-flyer) has terrified the people of Papua New Guinea for thousands of years, a monster of the skies that swoops down on its unsuspecting prey, often at night, and carries them off to its lair.
The world is full of tales of mythical beasts (the Loch Ness Monster, Bigfoot, the Yhetti) and expeditions costing millions of dollars have been carried out, often with the same result: little or no evidence, so the myth lives on.
Not so with the Ropen, or Dimorphodon Pterosaur, the flying reptile which is supposed to have died out 65 million years ago with the rest of the dinosaurs, because, according to American-based researcher Terrence Aym*, “Eyewitness reports – collected by determined exploration teams seeking strong evidence of the creatures – have led serious researchers to the conclusion that two distinct animals exist”.
Meet the Ropen and the smaller Duah, a relative. Eye-witness reports from teams of researchers go hand in hand with local folklore, telling of terrifying flying beasts with long beaks crammed with razor-sharp teeth, a long tail with a flange on the end and huge bat-like wings. Now, (see the original story from the link below) graphic real-time video evidence has been added, shot by intrepid researchers Jim Blume and David Woetzel, who have explored Papua New Guinea and several Pacific Isles.
Scouring the region for their prey, they encountered what they were looking for: flying dinosaurs with wingspans of ten to fifteen feet (eye witnesses say they can be much larger) and two different species which inhabit the dense forests and mountain regions of one of the remotest and least visited parts of the globe.
The Ropen (Demon-flyer) has terrified the people of Papua New Guinea for thousands of years, a monster of the skies that swoops down on its unsuspecting prey, often at night, and carries them off to its lair.
The world is full of tales of mythical beasts (the Loch Ness Monster, Bigfoot, the Yhetti) and expeditions costing millions of dollars have been carried out, often with the same result: little or no evidence, so the myth lives on.
Not so with the Ropen, or Dimorphodon Pterosaur, the flying reptile which is supposed to have died out 65 million years ago with the rest of the dinosaurs, because, according to American-based researcher Terrence Aym*, “Eyewitness reports – collected by determined exploration teams seeking strong evidence of the creatures – have led serious researchers to the conclusion that two distinct animals exist”.
Meet the Ropen and the smaller Duah, a relative. Eye-witness reports from teams of researchers go hand in hand with local folklore, telling of terrifying flying beasts with long beaks crammed with razor-sharp teeth, a long tail with a flange on the end and huge bat-like wings. Now, (see the original story from the link below) graphic real-time video evidence has been added, shot by intrepid researchers Jim Blume and David Woetzel, who have explored Papua New Guinea and several Pacific Isles.
Scouring the region for their prey, they encountered what they were looking for: flying dinosaurs with wingspans of ten to fifteen feet (eye witnesses say they can be much larger) and two different species which inhabit the dense forests and mountain regions of one of the remotest and least visited parts of the globe.
This challenges the widely held view that this kind of processing in the brain requires large numbers of neurons working together
This challenges the widely held view that this kind of processing in the brain requires large numbers of neurons working together, as well as demonstrating how the basic components of the brain are exceptionally powerful computing devices in their own right.
First author Tiago Branco said: "In everyday life, we constantly need to use information about sequences of events in order to understand the world around us. For example, language, a collection of different sequences of similar letters or sounds assembled into sentences, is only given meaning by the order in which these sounds or letters are assembled.
"The brain is remarkably good at processing sequences of information from the outside world. For example, modern computers will still struggle to decode a rapidly spoken sequence of words that a 5 year-old child will have no trouble understanding. How the brain does so well at distinguishing one sequence of events from another is not well understood but, until now, the general belief has been that this job is done by large numbers of neurons working in concert with each other."
Using a mouse model, the researchers studied neurons in areas of the brain which are responsible for processing sensory input from the eyes and the face. To probe how these neurons respond to variation in the order of a number of inputs, they used a laser to activate inputs on the dendrites in precisely defined patterns and recorded the resulting electrical responses of the neurons.
Surprisingly, they found that each sequence produced a different response, even when it was delivered to a single dendrite. Furthermore, using theoretical modelling, they were able to show that the likelihood that two sequences can be distinguished from each other is remarkably high.
Senior author Professor Michael Hausser commented: "This research indicates that single neurons are reliable decoders of temporal sequences of inputs, and that they can play a significant role in sorting and interpreting the enormous barrage of inputs received by the brain.
"This new property of neurons and dendrites adds an important new element to the "toolkit" for computation in the brain. This feature is likely to be widespread across many brain areas and indeed many different animal species, including humans."
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