Morgan, cosmic crashes & AAT

Bob Kobres (
Wed, 21 Dec 1994 14:44:14

I'm glad to see that Elaine Morgan is contributing to this group. I
doubt that anyone out there is as up-to-speed on AAT as she...

Though I have been interested in Hardy's idea of an aquatic biased
ancestor to better account for some of our physiology I have a perhaps
more flammable point to champion: The importance of factoring impact
events into our evolutionary picture.

Cosmic collisions energetic enough to disrupt a mature or slow changing
ecosystem are not that uncommon (1000 MT/10000 yrs minor disturbance of
food-chain, ozone level, may only affect region or hemisphere; 10000 MT/
100000 yrs major disruption of food-chain, ozone level, will probably
have global effects) and are likely to be bunched in time rather than
arriving at the "average" rates expressed above.

When events over 1000 mega-tons occur it is apt to become prime-time for
evolution. Competitors who were getting too big for their britches might
suddenly find size of appetite a distinct disadvantage, predator/prey
ratios can get way out of balance, enhanced ultra-violet allowed by an
ozone layer depleted by impact generated oxides of nitrogen can cause
vision and other problems associated with exposure to high energy radiation,
micro-organisms can have a field-day with roving hosts entering formerly
untrod areas in search of sustenance, etc. With regard to what would
actually happen for any given event the ifs are many and the facts are few
but the phenomenon of cosmic impact is natural and has yet to be properly
incorporated into our attempt to understand the evolutionary course of

I have a "discussion" I wrote some years back available on my home page
<> that explores why this
aspect of Earth history was under-rated (look under "research").

It is certainly possible that we stem from a line of primates which became
efficient in exploiting the resources of lakes and rivers during the last
protracted period of Mediterranean basin desiccation. Perhaps the grumpy
comet/sky-god of five million years ago said, as it delivered a suitable
missile to flash/splash-flood the low-land, "Let's see how long them scrawny
little swamp-things can tread water". Talk about selective pressure....
Fat and Wind won; the rest became sediment. :-)