Group
Here are excerpts from recent web articles with my comments are in square
brackets. I post these on other Lists I am on, so apologies if some of them
have already been posted here.
Steve
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http://dailynews.yahoo.com/h/nm/20001204/sc/fossils_find_dc_2.html ...
Yahoo! ... December 4 ... Scientists Find Fossils of Man's Earliest Ancestor
... NAIROBI, Kenya (Reuters) - ... scientists have unearthed fossilized
remains of mankind's earliest known ancestor that predate previous
discoveries by more than 1.5 million years ... They said the discovery of
"Millennium Man," as the creature has been nicknamed, could change the
way scientists think about evolution and the origin of species. The first
remains were discovered in the Tugen hills of Kenya's Baringo district ...
Since then the scientists have unearthed distinct body parts belonging to at
least five individuals, both male and female. "Not only is this find older than
any else previously known, it is also in a more advanced stage of
evolution," .... "It is at least six million years old, which means it is older
than the (previously oldest) remains found at Aramis in Ethiopia, which
were 4.5 million years old." "Lucy," the skeleton of Australopithicus
afarensis found in Ethiopia in 1974, is believed to have lived around 3.2
million years ago. An almost perfectly fossilized left femur shows the much
older Millennium Man already had strong back legs which enabled it to
walk upright -- giving it hominid characteristics which relate it directly to
man. A thick right humerus bone from the upper arm suggests it also had
treeclimbing skills, but probably not enough to "hang" from tree branches
or swing limb to limb. The length of the bones show the creature was about
the size of a modern chimpanzee .... But it is the teeth and jaw structure
which most clearly link Millennium Man to the modern human. It has small
canines and full molars -- similar dentition to modern man and suggesting a
diet of mainly fruit and vegetables with occasional opportunistic meat-
eating. ... Although no dating has been done on the remains just unearthed,
strata from where the fossils were recovered have been previously proven
... to show an age of six million years. ...The area is rich in calcium
carbonate and calcium phosphate that replace the organic material in bones
to form fossils in an environment sealed by lava or volcanic ash. Pickford
and Senut said they were confident the team would unearth even more
remains that could help form a near-perfect picture of Millennium Man. ...
See also: http://www.cnn.com/2000/NATURE/12/04/science.fossils.reut/
[If this is confirmed to be much older than Lucy and yet more bipedal, the
Australopithecines might be demoted as ancestral to humans? Also, at 6
mya, this would be very close to the putative chimp-hominid split, so this
would indicate a very rapid advance?]
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1036000/1036937.stm
BBC ... 23 November, 2000 ... Feathers fly over fossil reptile
Longisquama: Feathers or scales? A small, lizard-like creature that lived
220 million years ago is at the centre of renewed debate over whether it
had feathers and could fly. Canadian scientists have concluded that the
reptile had highly modified scales, rather than feathers, and therefore could
not have been the distant ancestor of birds. Earlier this year, a rival
scientific team said fossil remains of the animal, Longisquama insignis,
pointed to the presence of feathers. ... They argued that it was unlikely that
features as complex and specialised as feathers evolved more than once.
This theory challenges the convention that the first bird, Archaeopteryx,
arose 75 million years later, from small, meat-eating dinosaurs. Now,
palaeontologists ... have looked again at the fossils. They interpret what
appear to be impressions of feathers preserved in rock as the marks left by
long, thick scales. They wrote ... "We believe that the dorsal appendages of
Longisquama are highly modified scales, as suggested previously, rather
than feathers." They say Archaeopteryx remains the oldest known
forerunner of modern day birds. ... The Longisquama specimen was
discovered three decades ago in central Asia by a Russian palaeontologist
[Sharov] who specialised in insects. ... he described a row of long narrow
appendages down the animal's back, interpreting them as a frill of
extremely long scales. ... But in June, scientists ... came up with an
alternative theory. After examining every detail of the fossils, which include
most of the skeleton, they said they believed the unusual appendages
showed some of the most recognisable features of a modern-day feather.
Longisquama probably glided, they said, rather than flew, using its long
aerodynamic forelimbs for steering. The new analysis is unlikely to be the
final word in the debate. No-one has yet come up with a convincing
explanation for what the scale-like structures did. The Canadian team
believe Longisquama could have used its scales to frighten predators or to
attract a mate. Other experts say the appendages could have been a
"missing link" between scales and feathers. ... [It was hoped that
Longisquama would answer one of the valid points raised by the YECs:
"Why does no one ever find a fossil animal with half-scales turning
into feathers, or half forelimbs turning into wings? Such animals
must have lived in great numbers over long periods of time, but no
fossils of them have ever been found." (Morris H.M., "Scientific
Creationism," 1985, pp.85-86)
This lack of transitional *structures* (as opposed to transitional forms)
argues for rapid and directional major transformations of individual
structural features, rather than the slow, gradual natural selection of
numerous successive, slight, favourable, random variations envisaged by
Darwinism.]
http://dailynews.yahoo.com/h/nm/20001129/sc/life_dc_1.html ... Yahoo! ...
November 29 ... Scientists: Land Life Began 2.6 Billion Years Ago
LONDON (Reuters) - Life on land began more than 1.4 billion years earlier
than scientists had thought, geologists said ... Scientists have known that
microorganisms have lived in oceans for about 3.8 billion years, but they
weren't sure when early life forms made the transition to land. The oldest
proof of terrestrial life had been found in 1.2 billion-year-old fossils from
Arizona, but scientists in South Africa and the United States have now
discovered organic matter in 2.6 billion-year-old South African rocks.
"This places the development of terrestrial biomass more than 1.4 billion
years earlier than previously reported," Yumiko Watanabe ... said ....
Knowing when microorganisms made the transition from oceans to land is
important because it gives scientists new information about the presence of
oxygen that is needed to sustain life and the formation of the earth's
protective ozone shield. Hiroshi Ohmoto ... believes there are even earlier
samples of life on land. He and his colleagues are planning to scour sites in
Australia, Canada and elsewhere to find them. ... [Presumably because
water could shield from UV, the presence of life on land is evidence for an
ozone layer and hence an oxygen atmosphere? If so, this would seem to
render less plausible oxygen as a cause of the Cambrian Explosion ~ 600
myrs later?]
http://dailynews.yahoo.com/h/nm/20001201/sc/fossils_discovery_dc_1.html
... Yahoo! ... ... December 1 ... 'Living Fossils' Discovered Off South Africa
Coast ... PRETORIA (Reuters) - When Pieter Venter went on a
recreational deep dive off South Africa's northeast coast in October, he did
not expect to come across a living fossil. "I looked at it carefully and after
about six seconds I suddenly realized it was a coelacanth," .... A fish that
had been swimming in the seas for some 400 million years, the coelacanth
was believed to have been extinct for 70 million years until one was caught
by a trawler off South Africa in 1938 and identified by a museum curator.
... Venter's team found three coelacanths and filmed them at a depth of 115
meters (350 feet). ...The coelacanth -- known as "old four legs" because of
its extra fins -- inhabits deep water caves and canyons, far from the prying
eyes of most divers. .... "This discovery suggests that the coelacanth may
be far more widespread than was originally believed, perhaps anywhere
where you get these deep canyons and old reefs in tropical waters," .... The
only other known population -- which may be a distinct sub-species -- is on
the other side of the Indian Ocean, off Indonesia ... See also:
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1049000/1049818.stm
[More evidence of macrostasis. The Coelocanth is though not to have
changed in 450 myrs, yet presumably it has been subject to the same
genetic and environmental changes as its close relatives the Rhipidistians
which went on and gave rise to all land vertebrates including amphibians,
reptiles, mammals and birds! Darwinian evolution has no explanation. See
tagline for Dawkins' lame excuses.]
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1048000/1048280.stm
BBC ... 30 November, 2000 ... Lunar meteorites reveal life's troubles .. A
new study of Moon meteorites provides fresh evidence that the Earth and
its satellite underwent an intense period of cosmic bombardment just under
four billion years ago. An analysis of four of the 20 or so known lunar
meteorites suggests that the Moon's surface was melted by a torrent of
impacts. It is estimated that this lunar catastrophe would have lasted only
about 200,000 years but, in that time, nearly 2,000 large craters would
have been formed as well as many of the Moon's giant impact basins.
Scientists say that the Earth would have been bombarded to a far greater
extent and that the frequent impacts could have delayed the emergence of
life on the primitive world. ... But scientists know that these samples are
drawn from particular places on the lunar surface that do not necessarily
represent the Moon as a whole. ... . These would have been blasted off the
face of the satellite by large impacts and travelled through space for about a
million years before falling to Earth. About 20 lunar meteorites are known.
...Cohen and colleagues ... analysis of four lunar meteorites suggests that
the Moon underwent a particular phase of pummelling early in its history.
The ... samples were almost completely melted about 3.9 billion years ago.
... 750 million years after the Solar System was formed ... by four billion
years ago it had started to decline. So the new data suggests that there was
a brief period of resurgence. ... because the Earth is a bigger target than the
Moon our planet would have sustained at least 10 times the number of
punishing impacts. These would have melted the surface, vaporised any
oceans that were trying to form and filled the atmosphere with superhot
clouds of rock vapour. Any life that may have got started would have been
destroyed. Very little evidence of this past cataclysm remains on the Earth
... It is only by looking at rocks from the relatively unchanging Moon that
scientists have thrown new light on the common past of these space
companions. ... [There are traces of advanced photosynthesising bacteria ~
3.85 mya:
(http://www.uta.edu/geology/geol1425earth_system/images/gaia_chapter_10/Early_Life.htm),
and if the Earth's surface would have been melted and oceans vapourised
repeatedly up to ~3.9 bya, that leaves only 0.05 byrs (i.e. 50 million years)
for the Earth to cool down, life to get started and then get to the stage of
advanced photosynthesising bacteria! Also the million-year journey from
the moon makes panspermia less likely from Mars (see below) Maybe
Francis Crick was nearly right, when he wrote:
"An honest man, armed with all the knowledge available to us now,
could only state that in some sense, the origin life appears at the
moment to be almost a miracle, so many are the conditions which
would have had to have been satisfied to get it going." (Crick
F.H.C., "Life Itself," 1981, p.88)?]
http://dailynews.yahoo.com/h/nm/20001204/sc/space_mars_dc_3.html ...
Yahoo! ... December 4 ... Early Mars May Have Been Land of Lakes ...
PASADENA (Reuters) - Mars may have been a land of lakes in its earliest
period, with layers of Earth-like sedimentary rock resembling that found in
the Grand Canyon, NASA ... scientists said .... They added that the rocks
might harbor fossils of ancient Martian life if any existed. NASA's Mars
Global Surveyor spacecraft captured images ... of apparent sediments in
craters and chasms that look very much like Earth .... Although the data
received mixed reactions in peer reviews, it will probably alter the way
scientists regard Mars .... The red planet will no longer be likened to a
fossil like the Moon, but more "as a planet that may actually record in the
layers ... (actual) fossils (of biological matter or life)," .... The sedimentary
rock on Mars dates from the earliest span of Martian history, between 4.3
billion and 3.5 billion years ago. These sedimentary layers appear to be
made of fine-grained materials deposited in horizontal layers, much as
sedimentary rock is deposited on Earth ..."These images tell us that early
Mars ... may have been a lot more like Earth than many of us had been
thinking," ... Other forces can produce the appearance of sedimentary
rock, but the images show many uniformly thick layers, and this more than
likely means water was present .... "Some of the ... images of these
outcrops show hundreds and hundreds of identically thick layers, which is
almost impossible to have without water," Malin said. This latest evidence
of possible water on Mars in the past fuels interest in the planet, seen by
many as a virtual twin to Earth. Liquid water is seen as a prerequisite for
earthly life. "If there was life (on Mars) these are exactly the types of places
you would go to find remnants," .... "We feel there's no argument these
would be great candidates" for future exploration .... See also:
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1054000/1054621.stm &
http://www.cnn.com/2000/TECH/space/12/04/mars.ancient.lakes.02/index.html
[Interesting, but it sounds like not all the peer reviewers were convinced.
NASA has been criticised in the past for overstating its case in order to
preserve funding. This discovery sounds suspiciously timed to coincide
with an incoming Administration. I agree with Hugh Ross (see
http://www.reasons.org/reasons/meteor.html) that life could have been
created on Mars and transported to Earth (or vice-versa) by meteorite
ejecta. The Bible does not actually say where microbial life began. But
if it takes a million years for ejecta to get from the moon to Earth
(see previous), a distance of only ~ 384 thousand kms, it would presumably
take ~ 600 times as long to travel the 228 million kms from Mars to Earth,
and against the solar wind to boot.]
http://dailynews.yahoo.com/h/nm/20001110/sc/european_men_dc_1.html
... Yahoo! ... November 10 ... European Men Descend From 10
Forefathers - Study ... WASHINGTON (Reuters) - Virtually all European
men descend from 10 genetic forefathers who lived tens of thousands of
years ago in various parts of the continent, researchers reported ... They all
seem to have been descended from men who moved to Europe from the
Ural mountains of Central Asia and the Middle East in three successive
waves ... [they] ... studied the Y chromosomes of 1,007 men across Europe
and the Middle East. Only men have Y chromosomes and they are passed
down virtually unchanged from father to son. Mutations in the Y
chromosome can be used as a kind of molecular clock, and the researchers
found that 95 per cent of the men's genes could be traced to one of 10
categories. ... The genes match up nicely to what experts know about
European society. " ... three clusters of distinct geography and culture," ...
Basques and Western Europeans, ... Middle Eastern and the ... Eastern
European populations from Croatia, Ukraine, Hungary and Poland." ... The
oldest male lineage they found dates back to the Old Stone Age or
Paleolithic period, which ended 15,000 years ago. ... These people first
showed up in the archeological record as the Aurignacian people, who
were known for their rock art and fine tools. Some of the genes also show
up in Native American and Siberian people. "This observation suggests that
M173 is an ancient Eurasiatic marker that was brought in or arose in the
group of Homo sapiens (modern humans) who entered Europe and
diffused from east to west about 40,000 to 35,000 years ago, spreading the
Aurignac culture," ... Another marker, called M170, dates to about 22,000
years ago ...and is associated with the Gravettian culture. This group was
known for its Venus figurines, shell jewelry and for using mammoth bones
to build homes. The third group -- about 20 percent of the men -- seem to
date from more recent times, having come into Europe between 15,000 and
20,000 years ago ... These men were probably the first Neolithic farmers
who migrated from the Fertile Crescent in the Middle East ... [Interesting,
but it doesn't make clear if the dates came from the Y-chromosome
molecular clock or from dating archaeological artifacts.]
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"So, we have stasis. What are we to make of it? How do we explain it?
Some of us would say that the lineage leading to Latimeria [Coelacanth]
stood still because natural selection did not move it. In a sense it had no
'need' to evolve because these animals had found a successful way of life
deep in the sea where conditions did not change much. Perhaps they never
participated in any arms races. Their cousins that emerged onto the land
did evolve because natural selection, under a variety of hostile conditions
including arms races, forced them to. Other biologists, including some of
those that call themselves punctuationists, might say that the lineage
leading to modern Latimeria actively resisted change, in spite of what
natural selection pressures there might have been. Who is right? In the
particular case of Latimeria it is hard to know . ... Let us, to be fair, stop
thinking in terms of Latimeria in particular. It is a striking example but a
very extreme one ... It is conceivable that coelacanths stopped evolving
because they stopped mutating perhaps because they were protected from
cosmic rays at the bottom of the sea! - but nobody, as far as I know, has
seriously suggested this ... " (Dawkins R., "The Blind Watchmaker,"
[1986], Penguin: London, 1991, reprint, pp.246,247)
Stephen E. Jones | Ph. +61 8 9448 7439 | http://www.iinet.net.au/~sejones
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