Reflectorites
Here are belated excerpts from web articles for the period 9 - 11 August 2000,
with my comments in square brackets.
Steve
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http://dailynews.yahoo.com/h/nm/20000811/sc/humans_stoneage_dc_1.html
Yahoo! ... August 11 ... Study Shows Out-Of-Africa Migration to Israel ...
WASHINGTON (Reuters) - Magnetic dating has showed that prehumans
living in what is now Israel exported the latest Stone Age technology out
of Africa much earlier than believed, ... Their study adds to evidence that
humans and their ancestors came out of Africa in successive waves, each
time bringing better and better technology with them. The site, at Gesher
Benot Ya'aqov in Israel's Dead Sea Rift, is 780,000 years old ... Some limb
bones of the hominids who lived there, all members of the homo erectus
species, were also found. ... The technique is based on regular and known
flips of the Earth's magnetic field. ... As it happened, this site was right on
one of those shifts. "If the site been a little bit older or a little bit younger it
wouldn't have helped," Feibel said. Because the tools at the site are so
advanced, it shows that homo erectus was bringing new culture out of
Africa and to Europe and Asia much earlier than had been believed. The
tools belong to a style known as Acheulean, which requires sophisticated
planning and technological ability. ... [It is interesting this interaction
between Africa and Israel. It might even be that the real centre *was*
Israel and the satellite was Africa!]
http://news.bbc.co.uk/hi/english/sci/tech/newsid_871000/871930.stm BBC
... 9 August, 2000 ... Ice Age star map discovered The star map gives
insight into our ancestors' minds ... A prehistoric map of the night sky has
been discovered on the walls of the famous painted caves at Lascaux in
central France. It is a map of the prehistoric cosmos ... The map, which is
thought to date back 16,500 years, shows three bright stars known today
as the Summer Triangle. A map of the Pleiades star cluster has also been
found among the Lascaux frescoes. And another pattern of stars, drawn
14,000 years ago, has been identified in a cave in Spain. According to ...
Rappenglueck ... the maps show that our ancestors were more
sophisticated than many believe. ... The Lascaux caves, with their
spectacular drawings of bulls, horses and antelope, were painted 16,500
years ago. The caves may have been a prehistoric planetarium where the
stars were first charted. Discovered in 1940, the walls show the artistic
talents of our distant ancestors. But the drawings may also demonstrate
their scientific knowledge as well. The caves could be a prehistoric
planetarium in which humanity first charted the stars. The sky map has
been found in a region of the Lascaux caves known as the Shaft of the
Dead Man. Painted on to the wall of the shaft is a bull, a strange bird-man
and a mysterious bird on a stick. ... According to Dr Rappenglueck, these
outlines form a map of the sky with the eyes of the bull, birdman and bird
representing the three prominent stars Vega, Deneb and Altair. The ancient
star map shows a bull, birdman and a bird on a stick. Together, these stars
are popularly known as the Summer Triangle and are among the brightest
objects that can be picked out high overhead during the middle months of
the northern summer. Around 17,000 years ago, this region of sky would
never have set below the horizon and would have been especially
prominent at the start of spring. "It is a map of the prehistoric cosmos," ....
"It was their sky, full of animals and spirit guides." Seven sisters But the
sky map is not the only evidence that prehistoric man took a keen interest
in the night sky. Nearer to the entrance of the Lascaux cave complex is a
magnificent painting of a bull. ... Hanging over its shoulder is what appears
to be a map of the Pleiades, the cluster of stars sometimes called the Seven
Sisters. Inside the bull painting, there are also indications of spots that may
be a representation of other stars found in that region of sky. Today, this
region forms part of the constellation of Taurus the bull, showing that
mankind's identification of this part of the sky stretches back thousands of
years. ... Dr Rappenglueck has also identified a star map painted on the
walls of a cave in Spain 14,000 years ago. The Cueva di El Castillo cave...
contains a region called the Frieze of Hands. At the end of this remarkable
section can be found a curved pattern of dots. "Nobody paid much
attention to it," .... "But, it is obviously a drawing of the constellation we
call the Northern Crown. It is remarkable." The archaeologists who have
looked at Dr Rappengleuck's conclusions have so far agreed that they are
reasonable and that he may have uncovered the earliest evidence of
humanity's interest in the stars. [More evidence of early man's
sophistication?]
http://news.bbc.co.uk/hi/english/sci/tech/newsid_874000/874264.stm BBC
...10 August, 2000 ... Scientists delve inside protein maker Part of the
ribosome, the protein-making "factory" ... Scientists have obtained the
most detailed images ever seen of the ribosome, the molecular "factory"
found in cells. Ribosomes are the large, complex structures that assemble
amino acids into proteins, the important molecules that build and maintain
living organism like ourselves.... they have obtained the atomic structure of
an important part of the ribosome showing details 24 billionths of a metre
in size. The images support the idea that a component of the ribosome
called RNA - the simpler chemical cousin of DNA - was one of the first
self- replicating molecules to develop on Earth. ... The RNA and protein
that make up a ribosome are woven together in an intricate structure that
"reads" copies of the cell's genetic code and turns that information into
useful molecules using a supply of raw chemical components. The section
of the ribosome that the researchers have mapped is the portion that
catalyses the reactions that join those raw chemical components together.
The scientists say their images prove this function beyond doubt. To
produce their 3D map, scientists bombarded ribosome crystals with X-
rays. As the X-rays pass through and bounce off the atoms in the crystals,
they produce a diffraction pattern that can then be analysed to determine
the precise, three-dimensional shape of the molecules under study. ... "Our
previous maps of the subunit gave us some hints at the structure, but not
until we achieved the new resolution could we resolve the atomic structure
of all 100,000 atoms that are well ordered in the crystal," Professor Steitz
said. "I think we were amazed at each stage at the overwhelming
complexity of the molecular folding in the ribosome." The research team ...
say the structure provides intriguing insights into how the ribosome might
originally have evolved - perhaps as a "machine" to make short proteins. ...
the latest high-resolution structure offers a pathway to get to a far deeper
understanding of how cells manufacture proteins. "We're certainly not done
with the scientific challenges presented by the ribosome," said Professor
Steitz. ... [Another example of irreducible complexity? A ribosome is
essential for translating DNA's RNA transcript from the language of
nucleic acid into the language of proteins. Yet it is a "molecular `factory'"
of "100,000 atoms" of "overwhelming complexity" that has been conserved
across the whole of biology. Proteins cannot be made without ribosomes
and ribosomes are themselves made of protein!]
http://news.bbc.co.uk/hi/english/sci/tech/newsid_873000/873836.stm BBC
... 10 August, 2000 ... 'Antimatter factory' starts work The Antiproton
Decelerator (AD2) slows particles to a "leisurely pace" Scientists at
Europe's biggest high-energy physics laboratory have built an "antimatter
factory" to study why the world is made of matter, not its mirror image.
The experiment at Cern, in Geneva, aims to produce antiatoms, and to
slow them down long enough to conduct experiments on them. It is hoped
the results will explain why the world is made of matter rather than
antimatter - which only occurs naturally in cosmic ray collisions. Scientists
have been puzzling for years over the disappearance of antimatter, as the
Big Bang should have created the same amount of matter and antimatter,
and in principle the two should have wiped each other out. ... The
experiment will be looking closely for any difference between antimatter
and matter to explain the asymmetry. ... Landua, said: "We are looking at
how the Universe would look if it was made out of antimatter. Would there
be the slightest difference between our Universe and the Universe of
antiatoms?" Even a minute difference could explain why the world is made
of matter, and why antimatter disappeared. The antimatter factory ...
consists of a circular concrete box containing a ring of high-tech magnets.
It slows antiprotons, the antimatter equivalent of the proton, down to ...
one tenth of the speed of light. After trapping the antiprotons, the scientists
mix them with positrons, the antimatter equivalent of the electron, to
produce antihydrogen. ... Cern succeeded in creating nine antihydrogen
atoms in 1996, but they disappeared almost instantly. "These antiprotons
are an unruly bunch," .... "They disappear the moment they touch matter.
This is the first time we'll be able to study in great precision the behaviour
of antihydrogen and poke around with it because now we have the
technology to hold the antihydrogen in place to study it. ... [The idea that
this universe of 125 billion galaxies is the tiny residue left over after matter
and matter annihilated each other sounds to me like the Red Queen's
believing "six impossible things before breakfast". But then Lewis Carroll
was a physicist too! :-)]
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"Where is the Evidence for Chemical Evolution? The Chemical Evolution
Theory requires that an oxygen-free atmosphere existed for a considerable
period of time on the early Earth. Geological evidence from the early
PreCambrian, however, suggests that such primitive and secondary
atmospheres did not exist for any appreciable length of time. Supporting
evidence for this comes from studies of the ultraviolet photolysis of
methane to give polymeric materials. These studies suggest that under
primitive-Earth conditions the temperature around the Earth might have
been so high that methane would have disappeared. It would have broken
down into high-molecular-mass carbon polymer-deposited on the Earth's
surface, and hydrogen-escaping instantaneously into space. So an oxygen-
free atmosphere on primitive Earth, if it existed, would probably have
broken down in too short a time for a living system or chemicals of life to
have formed in it." (Brooks J., "Origins of Life," Lion: Tring, Hertfordshire
UK, 1985, pp.117-118)
Stephen E. Jones | sejones@iinet.net.au | http://www.iinet.net.au/~sejones
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