On Tue, 2 Sep 2008 12:34:04 -0700 (PDT), LarryG
wrote:

Have you actually read the book and examined the authors' thesis, or
are you pontificating and conflating their theory with the sensational
pseudoscience of the past?

I have the book (and I've read it). I've also read the original
Firestone, West, et al publication, and have followed the scientific
debate closely (my own specialty is meteoritics, although not
specifically impact studies).

As I said before, the evidence remains thin. There is a layer of
ash-like material found at many sites. But the evidence for component
materials that are of likely extraterrestrial origin is lacking in most
sampled sites. Also, common dating of the layer in different areas is
not established.

The book makes links to certain other things (the iron in tusks is just
ludicrous- widely recognized as completely misinterpreted, but the idea
that the Carolina Bays is related to an impact is very weak, as is the
association between the Younger Dryas and an impact. In addition, I read
a paper just a few weeks ago that rather solidly demonstrated no common
time of population decline in North American cultures between 9 and 15
thousand years ago. That is, no evidence of a single event causing
population loss.

In any case, the possibility that the Younger Dryas was caused by an
impact is a viable theory that is currently being investigated, but is
not well accepted by the majority of the meteoritical, impact,
archaeological, or paleontological communities. That doesn't mean it's
wrong, only that it needs a lot more work, and a few people are getting
way ahead of themselves in pushing the idea- in particular, trying to
connect it to geophysical and archaeological elements that are much
better explained by other things. What's needed isn't speculation (in
some cases wild speculation), but a lot more raw data, mainly in the
form of material samples.
_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com