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Re: Mesozoic terrain - who needs grass anyway ?




On Sun, 19 Jul 1998, Jeff Hecht wrote:
> The presence of low-slung grazers among dinosaurs, such as the ankylosaurs,
> stegosaurs, and ceratopsians, argues strongly that there was appreciable
> low plant cover during the mesozoic, even before angiosperms were widely
> recognized.

Good points, all.  But perhaps there are other reasons why grass was
special in its soil-binding properties.
1. Growing vertically allows higher density due to little shading of
leaves.
2. Wind pollination _required_ high density or at least was aided by it.
3. Though not unique to grass, C4 photosynethesis allowed phenomenal
growth rates, therefore recovery rates.
4. Rapid growth meant more dense decomposition layer in soil (not sure
about this point).
5. Tolerance to dessication meant great tracts of previously low-density
shrub land might be now productive and soil stabilized.
6. Rebounding more quickly after fires, therfore stabilizing soil.

None of this is to say other plants didn't exist at some density.  But
grass is special.