Re: Pollen From Permian/Triassic Extinction Show UV Induced Mutations

["David Marjanovic" <david.marjanovic@gmx.at>]

> There is no evidence for such a big impact at the end of the Permian,

Not at the moment.

> nor was the extinction very sudden.

Constrained to 8,000 years or less by cyclostratigraphy (on the mountain
called Gartnerkofel in Austria, you can see the Milankovic cycles in the
sediment), according to Rampino.

> Erwin indicated the fugal spike preceded marine exinction in China by
500,000 years.

Then why was there a fungal spike? (Globally!)

> Extinction on land in South Africa was apparently gradual.

Could you be more precise? How was the Signor-Lipps effect and suchlike
excluded?

> > I cannot imagine aridity being involved in a mass extinction.
>
>  Smith and Ward noted evidence for stepped extinction in South Africa
associated with a drier climate, or a "sudden, possibly catastrophic drought
at the end of the Permian."

A worldwide drought? How?

> > Global synchronous aridity would be needed for that
> > -- and why should that happen?
>
>  They suggested an increase in greenhouse gases.

:-) This would produce global humidity (via increased evaporation). As it
has in the early Eocene.