Re: Suspicious impact craters and iridium layers?

["Jaime A. Headden" <qilongia@yahoo.com>]

Tim Donovan (uwrk2@yahoo.com) wrote:

<Sure. Recently Arens found evidence of environmental deterioration, and waning
of certain plant and animal species in the upper Hell Creek. And some
dinosaurs, the centrosaurines and lambeosaurs, were already greatly diminished
or gone by the late Maastrichtian. Btw, the new age of c 65.5 Ma for the K-T
boundary already appeared in the JVP a while back.>

  Unfortunately, I have not seen any citations to back this up. Which Arens,
where, and what's the citations for decline of floral constituents of the
ecosystems in the Hell Creek? What was their sampling bias? Did they sample
only sites in the upper Hell Creek, or did they go towards the ill-sampled
lower Hell Creek and underlying basins to describe a decline in faunal
diversity more than ~2my in duration (which is apparently how long the Hell
Creek IS)?

  In addition, Tim Donovan has never answered the challenge of splitting and
lumping taxa as the reason for the so-called faunal declination of ceratopsians
in the Hell Creek, since his measured comparisons, usually from the early
Maastrichtian or late Campanian, are of such a distance and time (nearly 8my
before) as to be of less intrinsic value in measuring rates in the Hell Creek
or Lance Formations (which are latest Maastrichtian). Such taxonomic lumping of
hairs can easily lead to a reduction in so-called species diversity, as well as
the splitting of species in lower formations, such as the very-different
Campano-Maastrichtian Judith River Group (when it comes to geology).

  That the Hell Creek has a bias to certain forms of preservation (large
elements) whereas the Dinosaur Park Formation is biased towards smaller
specimens, but then with larger animals being preserved in bonebeds alone (we
do not have any small-animal bonebeds). Similarly, Donovan alludes to Asian
formations in his attempts to equate diversity in the Maastrichtian, at which
point the two regions had no contact and any faunal declination, unless
environmental (such as a meteoric catalyst), had a major part to play. The
Asian formations in play are, as in the Hell Creek region, restricted to a
single area and locus, and do not preserve the extent and stratigraphic
distribution from which to make such broad-reaching and uncites statements as
Donovan performs.

  We need to back this data UP, not allude to it as self evident. As is
everyone knows of the uncited Arens [paper? abstract? chapter? article?]
Donovan mentions.

  Cheers,

Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

"Human beings, who are almost unique in having the ability to learn from the 
experience of others, are also remarkable for their apparent disinclination to 
do so." --- Douglas Adams


                
__________________________________ 
Discover Yahoo! 
Have fun online with music videos, cool games, IM and more. Check it out! 
http://discover.yahoo.com/online.html