Dick Said,
>> The fossilized remains of dinosaurs and coal seams in Alaska and
>>Antarctica testify to their once warm-weather environs. Relief maps of
>>the Mid-Atlantic Ridge between Europe and the Americas show the
>>unmistakable stress of millions of years of internal pressure with
>>resultant sea floor spreading.
Glenn replied,
>Geologically, most of Alaska is is made up of terrain that formed a lot
>further south. Continental drift has rafted these various pieces of land
>onto North America and the fact that Mesozoic coals, limestones and
>dinosaurs are found in Alaska does not prove that the pole was warm. (see
>Jones, Cox and Coney, "The Growth of Western North America", Scientific
>American, 247:5 (1982)
And of course let's not forget that Antarctica was originally in the tropics
as part of Gondwanaland.
(Dick)
>>Massive dinosaurs leave huge bones, which make wonderful fossils. The
>>Cambrian explosion left a permanent record of hard-shelled marine
>> creatures that is impossible to ignore. Any soft-shelled predecessors
>>left scarcely a trace. The same could be said for any land-based
>>vegetation that might have been.
>>
(Glenn)
>Good try, but pollen is given off in vast quantities by grasses. And
>pollen is a very easily fossilized material and is very difficult to
>destroy. If grasses existed prior to the dinosaurs, grass pollen WOULD be
>found in rocks of those ages. I know several palynologists and they
>assure me that no pollen evidence of grass exists prior to the early
>tertiary. This suggestion simply will not work
This is absolutely true. I took a Palynology class as an undergrad. Spores
from primitive plants are found as early as late Silurian and everywhere
thereafter. Early gymnosperm pollen is found at the time of the dinosaurs,
but angiosperm pollen (and other plant parts for that matter) unquestionably
post-dates the first appearance of dinosaurs, and the grasses (and all monocots)are late-appearing angiosperms at that. Pollen and spores are in fact made of
pretty hardy materials and fossilize relatively easily, so the record is very
good. That's why there are so many palynologists in the employ of oil
companies!
-- Dave
-- Dave