Re: "The Anvil of Evolution"

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

> Here you go - a potentially controversial article to discuss until it
> looks like roadkill for awhile.

It isn't so controversial IMHO. Just add a few meteorites as the "disrupting
events", and it'll be orthodoxy within months, except for the quotations
below. Thanks for the interesting link!

> The short (including the author's credentials):
> http://www.earthwatch.org/pubaffairs/news/sill.html

"The crocodile-like ancestors of dinosaurs had been honed by adversity, when
some problem-perhaps a drought or a major disease outbreak-weakened the
therapsids' dominant position, and the dinosaurs took over."

Cute. A drought or a disease... what a good-night story :-}

> ......and the long of it:
> http://www.earthwatch.org/pubaffairs/news/sill_text.html

"At the end of the Permian period, the greatest extinction event in the
history of life on Earth took place: Approximately 95 percent of all species
disappeared. One prevailing theory is that drastic cooling of the planet led
to glaciation, which lethally reduced oxygen levels in the seas and
disrupted ocean circulation."

There was a big ice age in the Late Carboniferous and Early Permian, and a
little one in the Late Permian that ended before the end of the Permian.
There was no ice age at the end. IMHO the only realistic explanation for a
mass-extinction of this magnitude is a neat big meteorite.

"Standing erect meant early dinosaurs literally loomed head and shoulders
above the quadruped hoi polloi" -- whatever the last 2 words mean, this
depends on the length of the limbs, not on the difference between
quadrupedality and dinosaur-style bipedality (horizontal body).

"With such attributes, who cared about fancy anatomical innovations like
diaphragms, elegantly differentiated teeth, or a secondary palate? The early
dinosaurs managed well without them."

After all, they had something better than a mammal-style (or croc-style)
diaphragm.

"rhync[H]osaurs (bulky, tusked and beaked herbivores related to lizards)."

Neither (closely) to lizards nor to tuataras, but to (Archosauriformes +
Prolacertiformes), unless someone has meanwhile smashed that phylogeny, too.

> The pdf file has the graphics:
> http://www.earthwatch.org/pubaffairs/news/sill.pdf

Warning: This hung my computer several times. Don't use the wheel on your
mouse if you have one.