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COSMIC IMPACTS PUNCTUATED HUMAN EVOLUTION

Liverpool John Moores University
Press Office
Janet Martin
0151 2313583
j.martin@livjm.ac.uk

Press Release
17 April 2001

The theory of gradual and uninterrupted human evolution has been called into
question after two researchers found that human evolution has been
repeatedly punctuated by large-scale cosmic catastrophes.

One of the biggest problems that has puzzled researchers for generations is
the question why almost all hominids, i.e. the 14 known species of human
ancestors, have become extinct during the last 5 million years. Ever since
Charles Darwin, the predominant explanation has been that our
ancestors were slowly and gradually replaced by more advanced species due to
their inferior genes and their failure of adaptation, and that modern humans
survived due to their superior "fitness".

In recent years, however, researchers have become aware that the fossil
record does not show gradual but rather abrupt change. Neither the causes
for the sudden gaps in the fossil record nor the underlying dynamics of
hominid extinctions have been determined yet.

Dr Benny Peiser, a social anthropologist at Liverpool John Moores University
and Michael Paine, an impact researcher from the Planetary Society in
Australia, have come up with new findings that may help to solve this
puzzle. Peiser and Paine have calculated that the most likely cause of
hominid extinctions may be associated with the more than 20 globally
devastating catastrophes that occurred over the last 5 million years. Dr
Peiser presented the findings last Thursday at the Charterhouse Conference
2001 "Celebrating Britain's Achievements in Space".

It is these large-scale impacts that had a catastrophic and detrimental
affect on human evolution. A number of significant climatic downturns, well
documented in the paleo-environmental and climatological records are
directly associated with such major impact. Episodes of cometary or
asteroidal impacts punctuating human and societal evolution should thus be
looked upon as natural agencies determining evolutionary regressions,
extinctions and macro-mutations.

"The reason that Homo sapiens have survived in spite of these global
disasters has little to do with the traditional explanations given by
neo-Darwinists. It is sobering to realise that we are alive due to cosmic
luck rather than our genetic makeup," says Dr Peiser. "After all, the
populations of hominids and early modern humans were extremely small. Had
any of these impacts occurred in the proximity of these population groups,
we might also have gone the way of the dodo."

Planetary Society's Michael Paine agrees: "Just over 2 million years ago an
asteroid estimated to be 2km in diameter struck the Southern Ocean, south
west of Chile. Had it struck land the environmental consequences might have
been much worse. If the collision had occurred a few hours early southern
Africa might have been wiped out, along with our ancestors."

Large impacts not only cause severe climate disruption (mainly darkness and
cooling) but can also lead to the loss of the ozone layer (particularly with
ocean impacts that propel chlorine into the upper atmosphere), severe acid
rain and toxins. "Such environmental mega-catastrophes may not only wipe out
directly affected hominid species. What is more, the abrupt loss of the
ozone layer and the sudden release of toxins may even affect the DNA in some
unknown manner, thus triggering macro-mutations, including the sudden
reorganisation of entire genomes," Dr Peiser suggests.

Given the rather conservative impact estimates, "it is almost certain that,
for several years at least, creatures on Earth had to endure very severe
conditions. Although the physical Earth heals quickly from impacts its
inhabitants might not do so well and the course of evolution may well have
changed due to these and similar impact events," says Michael Paine.

-------

The findings are calculated on the basis of the generally accepted "impact
rate" (i.e. the rate of cosmic impacts calculated from terrestrial and lunar
impact craters together with the currently observable flux of asteroids and
comets in the solar system). A computer simulation of cosmic impacts over a
5 million year period was chosen to give an indication of the environmental
disruption that have occurred during the evolution of our species.

These consequences can be categorised into:

A. Local - devastation over a radius of tens of kilometres. No serious
regional or global consequences

B. Moderate regional - devastation over a radius of hundreds of kilometrees
(the size of a small country). Short term regional climatic problems.

C. Severe regional - devastation over a thousand kilometres (the size of a
large country). Severe regional climatic disruption. Mild short-term global
climatic disruption (year without Summer).

D. Moderate global - devastation over thousands of kilometres (continents).
Severe global climate disruption for several years. Global food chain
failures

E. Severe global - global firestorms (ballistic re-entry of impact debris).
extreme global climate disruption for decades to centuries. Extinctions.

For everything except the last category the effects on early human
populations depend proximity to the impact - a matter of luck. In addition
to climate disruption (mainly darkness and cooling), the larger impacts
could lead to global warming due to the greenhouse effect (water and carbon
dioxide), lose of the ozone layer (particularly with ocean impacts that
propel chlorine into the upper atmosphere), acid rain and toxins.

The simulation looked at the *worst* event in each of 5000 millennia. It
therefore gives an *underestimate* of the total number of impacts.

The program recognises 5 outcomes of an asteroid or comet colliding with the
Earth:

* The object skims the atmosphere and flies harmlessly back into space. This
happened in 2% of the millennia.

* The object explodes above land in an airburst similar to an atomic
explosion. This happened in 17% of the millennia.

* The object impacts the land and forms a crater. This happened in 11% of
the millennia.

* The object explodes in an airburst above an ocean. This was the most
frequent outcome, accounting for 41% of millennia. Fortunately, until
recently, most of these impacts would have been harmless to land dwelling
creatures.

* The object impacts the ocean, forming tsunami and, possibly, ejecting vast
quantities of water and salt into the atmosphere. This happened in 28% of
the millennia. (Larger impacts may also reach the ocean bottom and cause
similar effects to a land impact)

Over the period of the simulation some 57% of millennia suffered an impact
that would potentially have consequences for land-dwelling creatures. In
most cases they would only be affected in they were close to the impact
site. The situation is different now with significant human populations
living in low-lying coastal areas.

Size impactor (The letters refer to the typical environmental consequences.)

500 to 900m (C) - 108 events
1km to 1.5km (C/D) - 24 events
1.6km+ (D/E) - 13 events

Craters (The letters refer to the typical environmental consequences.)

Over the 5000 millennia a total of 552 craters were formed on land. Of
these:

* 477 were less than 5km in diameter (A)
* 64 were between 5 and 10km in diameter (B)
* 9 were between 10 and 20 km in diameter (C) and
* 2 were more than 20km (D).

There were also 6 ocean impacts that could be expected to produce moderate
to severe global climate disruption (D/E), particularly destruction of the
ozone layer. Three of these involved transient craters more than 50km in
diameter and would probably have reached the ocean floor.

Therefore during this simulation severe climate disruption occurred, on
average, every million years (2 land impacts and 3 ocean impacts).

The findings by Peiser and Paine are underpinned by a significant number of
large impact craters. So far, 32 impact craters have been discovered that
are younger than 5 million years. One is 52km in diameter, 3 are between 10
and 20 km, 1 is between 5 and 10km and 25 are less than 5km in diameter.
However, it should be noted that it takes very unusual conditions to
preserve craters of this size for more than a few hundred thousand years.

Background material can be found at
http://www4.tpg.com.au/users/tps-seti/spacegd.html

Contact:

Dr Benny Peiser
b.j.peiser@livjm.ac.uk
0151 231 4338 (office)
0151 428 7250 (home)
0771 459 0623 (mobile)

Michael Paine
mpaine@tpgi.com.au
+612 94514870

=======
DID COMETS WIPE OUT OUR ANCESTORS' RIVALS?

From The Daily Post, 17 April 2001

By Rob Brady
Daily Post Staff

Researchers at Liverpool John Moores University are challenging the
traditionally held theory of human evolution.

For years, scientists have been baffled about why virtually all of the 14
known species of pre-humans, called hominids, became extinct during the past
5m years, leaving only Homo sapiens to develop into modern man.

Ever since Charles Darwin published his theory of evolution in the 19th
century, it has been accepted that the answer lay in the survival of the
fittest. Homo sapiens was more able to adapt to global chances than other
hominids.

However, a team from JMU has come up with a new theory which calls this
conventional wisdom into question.

The university's social anthropologist, Dr Benny Peiser, and Michael Paine,
an impact researcher from the Planetary Society in Sydney, Australia,
believe that large-scale cosmic catastrophes hold the key. They suggest the
demise of the hominids could have been down to simply being in the wrong
place at the wrong time.

They argue that available fossil records do not show that the creatures were
gradually replaced by a more modern and adapted species. Instead, a string
of abrupt and devastating global incidents may have been responsible for
sealing their fate.

Dr Peiser argues that severe climatic changes brought about by the earth
being struck by comets and asteroids was a key component in the shaping of
human evolution.

He said: "The reason that Homo sapiens have survived in spite of these
global disasters has little to do with traditional explanations given by
neo-Darwinists. It is sobering to realise that we are alive because of
cosmic luck rather than our genetic make-up."

"After all, the populations of hominids and early modern humans were
extremely small. Had any of these impacts occurred in the proximity of these
groups, we might also have gone the way of the dodo."

Mr Paine said: "Just over two million years ago an asteroid estimated to be
two kilometres in diameter struck the Southern Ocean, south west of Chile.
Had it struck land, the environmental consequences might have been much
worse. If the collision had occurred on southern Africa, it might have wiped
it out along with our an ancestors."

Dr Peiser argues that big cosmic impacts not only cause severe disruption to
the earth's climate, including a significant drop in temperatures and long
periods of darkness, but may also have led to other environmental disasters,
such as the loss of the ozone layer, the formation of acid rain and other
toxic pollutants.

He added: "Such catastrophes may not only have wiped out directly hominid
species, the abrupt loss of the ozone layer and the sudden release of toxins
may even have affected the DNA in some unknown manner, thus triggering
macro-mutations."

Copyright 2001, Daily Post

=============
ASTEROIDS 'AFFECTED HUMAN EVOLUTION'

http://news.bbc.co.uk/hi/english/sci/tech/newsid_1272000/1272368.stm

By BBC News Online science editor Dr David Whitehouse

Impacts by asteroids may have affected the course of human evolution,
according to two researchers studying how often the Earth has been struck in
the past.

They say that rather than gradual and uninterrupted human evolution, the
ascent of mankind could have been influenced by frequent cosmic
catastrophes.

Their work, they say, explains one of the biggest problems that has puzzled
researchers for generations: why almost all human-like creatures or
hominids, have become extinct during the past five million years.

According to traditional theories of evolution, our early ancestors were
slowly and gradually replaced because they failed to compete with other
human species that had superior "fitness".

But according to Dr Benny Peiser, a social anthropologist at John Moores
University in Liverpool, UK, and Michael Paine, an impact researcher from
the Planetary Society in Australia, the most likely cause of hominid
extinctions may be more than 20 globally devastating catastrophes that
occurred over the last five million years.

"The reason that Homo sapiens has survived in spite of these global
disasters has little to do with the traditional explanations given by
Neo-Darwinists," Dr Peiser told BBC News Online.

"It is sobering to realise that we are alive due to cosmic luck rather than
our genetic make-up," he added.

"After all, the populations of hominids and early modern humans were
extremely small. Had any of these impacts occurred in the proximity of these
population groups, we might also have gone the way of the dodo."

Michael Paine of the Planetary Society agrees: "Just over two million years
ago an asteroid estimated to be 2 km (1.2 miles) in diameter struck the
Southern Ocean, south west of Chile. Had it struck land the environmental
consequences might have been much worse.

"If the collision had occurred a few hours earlier, southern Africa might
have been wiped out, along with our ancestors."

Simulation

The researchers performed a computer simulation of cosmic impacts over a
five million year period to give an indication of the environmental
disruption that may have occurred during the evolution of our species.

The simulation looked at the worst event in each of the preceeding 5,000
millennia.

They found that over the period of the simulation some 57% of millennia
suffered an impact that would potentially have had consequences for
land-dwelling creatures.

Copyright 2001, BBC



CCCMENU CCC for 2001

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