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Pastimes : Let's Talk About Our Feelings!!! -- Ignore unavailable to you. Want to Upgrade?


To: J. C. Dithers who wrote (93631)1/13/2005 11:32:46 PM
From: average joe  Respond to of 108807
 
New species may have relatives in next villlage

John Vidal
Thursday January 13, 2005
The Guardian

A growing number of scientists are challenging the sensational discovery last year of a new species of one-metre-tall intelligent humans whose 13,000-year-old bones were said to have been found in an Indonesian cave.
According to some leading anthropologists in Australia, Indonesia and elsewhere, Homo floresiensis is not "one of the most important discoveries of the last 150 years" as was widely reported last October, but a pygmy version of modern Homo sapiens with a not uncommon brain disease.

Now a leading critic of the Homo floresiensis theory is to send researchers to a village near the cave where the bones were excavated to measure an extended family group whose males may be just a few inches taller than the skeleton.

The Guardian has travelled to the village and interviewed three male members of the family, the shortest of whom was 1 metre 25cm (4ft), compared with the estimated 1 metre of the skeleton.

Professor Teuku Jacob of Gadjah Mada University in Yogyakarta said he would compare the villagers' measurements with those of the bones.

"It is quite possible that there are pygmy people living in the area who are related to the people found in the cave."

The dispute over the bones is dividing evolutionists between those who believe modern humans came "out of Africa" and those who say that they evolved in many parts of the world. But it is now getting personal with both sides hurling insults at each other.

Prof Jacob, who has been accused by the Australian scientists who led the excavation of "kidnapping" the bones from Indonesia's centre of archaeology, said the Australian team had "rushed" their work and lacked expertise.

guardian.co.uk



To: J. C. Dithers who wrote (93631)1/13/2005 11:34:14 PM
From: average joe  Respond to of 108807
 
Celestial 'spring' pours out cosmic rays
13:44 13 January 2005

Chandra X-ray Observatory

A celestial "spring" of mysterious particles that slam into Earth from all directions may have been discovered by a US physicist.

The underlying source of the ultra-high-energy cosmic rays (UHECRs) remains one of the greatest puzzles in physics, but this new work suggests it arises in known phenomena rather than in exotic, hypothetical forms of matter.

Just 100 of these charged particles have been observed in the last decade. They appear to be mostly protons and atomic nuclei. Magnetic fields - with an unknown source - accelerate the particles to almost the speed of light. This makes UHECRs so energetic that some astronomers doubt that even the most extreme cosmic events, such as the explosive birth of a black hole, could account for their power.

They are also extremely rare, hitting any given square kilometre on Earth just once every century. And they come from all over the sky - deflected from their original paths by any magnetic fields they happen to encounter in space.

But this deflection is weaker for higher energy particles than lower energy particles which can travel in relatively straight lines. So astronomers had scanned the skies for "point sources" that spew out a number of these particles and up until now had found only a handful where two UHECRs have come from the same region.

Particle quintet
But Glennys Farrar, a physicist at New York University, New York City, US, has used a new analysis technique to identify five UHECRs appearing to originate from the same patch of sky. That quintet has just a one in 10,000 chance of being a fluke, Farrar says.

The particles were among 97 UHECRs observed with two experiments. A telescope in Utah, US, called HiRes, caught sight of the streaks of light produced by 40 such cosmic rays as they blazed into the atmosphere and generated a cascade of secondary particles. And an array of ground detectors in Japan, called AGASA, measured the secondary particles from 57 UHECRs.

The five cosmic rays in question arrived over a period of 10 years - an unsurprising time lag since any intervening magnetic fields could have had a variable accelerating effect on particles, Farrar explains. They came from a patch of sky about as large as a full Moon seen from Earth and from the direction of Ursa Major - also known as the Big Dipper or the Great Bear.

Galactic collisions
When Farrar searched celestial databases to find what objects lay along that line of sight, she found essentially nothing but empty space for quite some distance. But then, at 550 million light years from Earth, she discovered two crowded galaxy clusters - containing about 20 galaxies - crashing into each other.

That suggests the five cosmic rays were accelerated to high energies by the galactic collisions themselves or by some other phenomena within the galaxies. It also suggests the five UHECRs remained relatively close to each other in space because only weak magnetic fields - if any - exist in the void, allowing the particles to sail unencumbered straight through to Earth. "Magnetic structure [in the void] is something like a cloudy day, where there are little spots of blue sky," says Farrar.

She says the underlying source of the cosmic rays could be a long-lived process - such as a super-massive black hole slurping up surrounding matter - or magnetic shocks produced by the colliding galaxy clusters. Or it could be produced by a sudden, cataclysmic event like such as an explosion of matter and energy that signals the birth of some black holes, giving off a gamma-ray burst.

Farrar is scouring archival data for gamma-ray bursts in that part of the sky and hopes to get the Chandra X-ray Observatory to search for signs of feeding black holes. But the analysis, if confirmed, does seem to rule out the more outlandish possibilities for the birth of UHECRs, such as the decay of invisible, super-heavy matter left over from the big bang. Those speculative particles would not be electrically charged and remain unaffected by magnetic fields, so they would not cluster in space.

Farrar is presenting the work on Thursday at a meeting of the American Astronomical Society in San Diego, California.

newscientist.com



To: J. C. Dithers who wrote (93631)1/14/2005 2:28:57 AM
From: Grainne  Read Replies (1) | Respond to of 108807
 
This seems to be a fairly substantial site dealing with transitional fossils (and there are others).

It seems that there are a lot of them. I am not extremely knowledgeable about this subject; perhaps you could explain to me why this long list of fossils are not transitional?

talkorigins.org



To: J. C. Dithers who wrote (93631)1/14/2005 9:50:03 AM
From: epicure  Read Replies (1) | Respond to of 108807
 
What can one do?

You keep saying transitional fossils have not been found, when they have been. I give you links to show you they have been found, and you keep claiming they have not been. I thought excusing you by ignorance was pretty generous. It now begins to look willful, which is something else again.

"If you claim to have seen "transitional fossils" than I doubt you are clear on what the term means..."

I'm very sure you don't know what the term means. If you did, you would have understood that they already exist.

People who believe as you do will no doubt support you in your belief system. No one else will. I try not to argue religion with people anymore, since arguing belief based systems is pointless. It is clear that what you have going on is a belief based argument. It was my mistake to think you were arguing about science, or were interested in it.