Hey, I'm sorry I didn't get around to this earlier. It's a busy week.
Originally posted by TheWayISeeIt
Reply to Byrd
Here is a link to another recent theory from my earlier threadwhich addresses some of
your concerns with the black mat and animal extinctions. This theory is taking into consderation fullernes and nano-diamonds being where they should
not, the lynch-pin holding the cometary theory together.
I confess I didn't read the thread. I had read some of it at the time you posted, but was on one of those very busy periods and decided to not
Marusek's idea doesn't impress me... and let me go into a bit of detail on why. In order for it to work...
* the impactor would have to have some sort of selection method where it kills off certain animals of a certain size (like the horses and camels) and
leaves other animals of the same size living in the same area (deer, moose) untouched.
* the entire human population of the continent would have had to NOT gone further inland on the American continent ... and would have had to stay
within a mile or two of the (then) shore.
* these shore-living humans would have eaten fish and clams and oysters and birds but ... would have had to run several miles into the interior of the
continent to put down shell mounds and campsites and then run back to a comfortable civilization (or tribal area) within a mile or two of the
* they would have to be so neurotically attached to the shore that they wouldn't move farther inland as the water slowly rose (the rate of rising was
irregular... and it rose between several inches to a foot in a year.)
* the impactor would have had to kill some species quickly and others very slowly. It would have to leave elephants alive in Africa while wiping them
out in America, and kill camels in North America but not South America (llamas) and kill horses in the Americas while leaving them alive elsewhere.
I did look at your link the cometary impact one.
as well as the
link. I'm not skeptical of meteors hitting
the Americas... in fact, there is Meteor Crater in Odessa where a fair sized one hit just about the end of the Ice Age. The crater, however, is only
a mile or so across and while it probably killed everything for miles around and tossed dust into the atmosphere, it wasn't anything along the lines
of the one that killed the dinosaurs.
Given that these things can travel in "packs" (as a comet breaks up), it wouldn't entirely surprise me that we'd find several meteor impacts that
are about the same age. It wouldn't surprise me that a single meteor impact hitting an area where the species were pretty specialized and were in
decline might wipe something out (like, say, one hitting Africa close to where the last of the cheetahs are living. They aren't very genetically
diverse and they're being pressured by civilization, so some ecological disaster could tip the balance and force them into extinction.)
But the rest of it doesn't match up. Mammoths and mastodons died out over a period of thousands of years. The last of the giant ground sloths and
giant armadillos were certainly around during the last of the ice age, but evidence shows they'd been in decline for awhile... and shows that the
habitat was changing (but not in the space of months. The change was over centuries.)
They're still arguing over the genetic results in modern Native Americans. I tend to go with this one that says three migrations rather than the
single migration ( www.genomeweb.com...
) simply because of the data of the language
families and language isolates. The languages show pretty clearly that certain tribes (language families) ended up in certain areas, with pockets of
older language families surrounded by migrants (I'm thinking particularly of the Chumash languages... one of the oldest language families on the
So that's in part why I have never found the theory very convincing. I could certainly believe that one or more smaller meteors (like the one in
Odessa) hit the planet about the end of the Ice Age. I could believe that they would affect global weather for months... or even up to a year (or
two.) But I don't see any good evidence of human societies living only on the edge of the sea where they build monumental cities (with no farming
areas to support them) and then die because they're too scared to move away from the slowly rising waters. And I don't see good evidence that shows
the animals that went extinct all went into a certain area where they all dropped dead within a year or two.
And that's my objection to the theory. Or, at least, some of them.