quote:
Where are the planktonic foraminifera, for instance? Why no marine organisms larger than, say, 100um in those midwest soils? Hmm."
This may not add anything to this discussion but I have personally collected and observed foraminifera from the Upper Cretaceous Selma Formation chalk in northeast Mississippi. I've read there are some 60 species occuring in the formation but in one sample of the formation in an hour of casual looking under a basic light microscope I only turned up one obvious species, which I did not attempt to identify. There were shards of silica also present, but whether these were diatoms, volcanic dust, sponge spicules, or something else I don't know.
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