| Topic: |
Religions > Atheism |
| User: |
"Michelle Malkin" |
| Date: |
18 Oct 2007 07:44:12 PM |
| Object: |
Trip To Beach A Milestone In Human Evolution Study |
http://www.world-science.net/othernews/071017_humans-beach.htm
Trip to beach a milestone in human evolution: study
Oct. 17, 2007
World Science staff
One of the first things modern humans did when they evolved was head for
the beach-a setting that may have served as a crucible and driver of our
evolution, a new study suggests.
Its authors say they've found evidence of the earliest known people
with cultural trappings of the "modern" human species, such as use of
symbols and innovative tools, about 164,000 years ago.
Unlike their more primitive ancestors, this group lived near and
harvested the sea-probably pushed by a dry, frigid climate to try this
as a new survival gambit, according to the scientists.
"We believe that on the far southern shore of Africa there was a small
population of modern humans who struggled through this glacial
period using shellfish and advanced technologies," said
paleoanthropologist Curtis Marean of Arizona State
University in Tempe, Ariz., one of the researchers. "Symbolism was
important to their social relations."
The people, who dwelt in a large cave overlooking the Indian Ocean,
might have been "the progenitor population for all modern humans,"
added Marean. The findings appear in the Oct. 18 issue of the research
journal Nature.
Exactly when the modern human species emerged is debated. Some
research has also pointed to a long delay between the origin of
"modern" anatomy and, later, of "modern" behavior. A 2005 study, for
instance, found that modern anatomy arose by 195,000 years ago. But not
until about 100,000 years later do signs of modern behavior appear,
findings published last year suggested: this evidence consisted of beads
thought to attest to the use of symbols.
The new study, then, doesn't present the oldest evidence ever
advanced for "modern" anatomy. But it does claim by far the earliest
evidence of "modern" behavior, pushing back the estimate of its
origin by tens of thousands of years.
The work also could shed light on our species' migration out of its
African birthplace, as some theories hold that this journey followed
coastlines, scientists said. "Coastlines generally make great
migration routes," Marean remarked. "Knowing how to exploit the sea
for food meant these early humans could now use coastlines as productive
home ranges and move long distances."
The newly identified, ancient coast dwellers used a bright red coloring
and "expanded their diet to include shellfish and other marine
resources, perhaps as a response to harsh environmental
conditions," added Marean.
Most scholars agree based on genetic and fossil evidence that modern
humans, Homo sapiens, evolved in Africa between 100,000 and 200,000
years ago. But archaeological sites from that time are rare in the
continent; and given its huge size, it's unclear just where the step to
modernity occurred.
"The world was in a glacial stage" for most of this time, and much of
Africa was dry or desert, Marean said. "There are only five or six
places in all of Africa where humans could have survived." Marean said
he looked for a "perfect site" to explore by studying ocean currents,
climate data, geological formations and other data. He settled on
the Cape of South Africa at Pinnacle Point as a spot for
investigation.
The results fulfilled all his hopes, he said.
One finding was "bladelets," less than a centimeter wide, that "could be
attached to the end of a stick to form a point for a spear, or lined up
like barbs on a dart," Marean said. This shows people "were already
using complex compound tools. And, we found evidence that they were
using pigments, especially red ochre, in ways that we believe were
symbolic." The team reported finding 57 pieces of this material, many
apparently ground for use as a coloring agent.
Archaeologists view symbolic behavior as a clue that language in
the modern sense may have been present, he added.
Dating the finds-which also included shellfish remains-was a
challenge, Marean said. This time period is beyond the range of the
most common dating technique, carbon dating. But two other
cutting-edge methods served to fill the gap, he added. One, known as
luminescence dating, involved gauging when individual sand grains
were last exposed to light; thousands of grains were measured.
The discoveries change our picture of early modern human evolution
in several ways, Marean added. "Generally speaking, coastal areas
were of no use to early humans-unless they knew how to use the sea as a
food source," he said. "For millions of years, our earliest
hunter-gatherer relatives only ate terrestrial plants and animals.
Shellfish was one of the last additions to the human diet before
domesticated plants and animals were introduced." The previously
earliest evidence for human use of marine resources and coastal
habitats dates to about 125,000 years ago, he said.
In a commentary published with the study, two scientists not involved
with it wrote that it provides "strong evidence" for its claim of early
modern human behavior at Pinnacle Point, whose area is now dotted
with golf resorts. "The site provides a rare glimpse into human
adaptation to coastal conditions," added the writers, Sally
McBrearty of the University of Connecticut and Chris Stringer of
London's Natural History Museum.
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| User: "johac" |
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| Title: Re: Trip To Beach A Milestone In Human Evolution Study |
19 Oct 2007 01:56:03 AM |
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In article <XOSdnU7p9ZpHYIranZ2dnUVZ_j2dnZ2d@comcast.com>,
"Michelle Malkin" <hypatiab7@comcast.net> wrote:
http://www.world-science.net/othernews/071017_humans-beach.htm
Trip to beach a milestone in human evolution: study
Oct. 17, 2007
World Science staff
One of the first things modern humans did when they evolved was head for
the beach-a setting that may have served as a crucible and driver of our
evolution, a new study suggests.
Its authors say they've found evidence of the earliest known people
with cultural trappings of the "modern" human species, such as use of
symbols and innovative tools, about 164,000 years ago.
Nice article, but what's with the hyphens?
--
John #1782
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| User: "Michael Gray" |
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| Title: Re: Trip To Beach A Milestone In Human Evolution Study |
19 Oct 2007 07:39:15 AM |
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On Thu, 18 Oct 2007 20:44:12 -0400, "Michelle Malkin"
<hypatiab7@comcast.net> wrote:
http://www.world-science.net/othernews/071017_humans-beach.htm
Trip to beach a milestone in human evolution: study
Oct. 17, 2007
World Science staff
:
I should like to read this, but is almost indecipherable.
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| User: "Al Klein" |
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| Title: Re: Trip To Beach A Milestone In Human Evolution Study |
19 Oct 2007 09:56:26 AM |
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On Fri, 19 Oct 2007 22:09:15 +0930, Michael Gray
<mikegray@newsguy.com> wrote:
On Thu, 18 Oct 2007 20:44:12 -0400, "Michelle Malkin"
<hypatiab7@comcast.net> wrote:
http://www.world-science.net/othernews/071017_humans-beach.htm
Trip to beach a milestone in human evolution: study
Oct. 17, 2007
World Science staff
I should like to read this, but is almost indecipherable.
Notepad and a single global replace fixes that.
--
Al at Webdingers dot com
"I've never had a problem with pollution. If God didn't want smoke in the air,
he wouldn't have told us to burn witches."
- Stephen Colbert
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