Not directly mollusk related, but planktonic foraminiferal "handedness" may
be completely genetic as the different "forms" are now being assigned to
different species. See Kucera, M., and Kennett, J.P., 2000, Biochronology
and evolutionary implications of late Neogene California margin planktonic
foraminiferal events: Marine Micropaleontology, v. 40, p. 67-81.
Best,
Chuck
Charles L Powell, II
Western Earth Surface Processes Team, MS 975
U. S. Geological Survey
345 Middlefield Rd.
Menlo Park, CA 94025
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(650) 329-4985
Andrew Grebneff
<[log in to unmask] To: [log in to unmask]
TAGO.AC.NZ> cc:
Sent by: Conchologists List Subject: Re: fake shells... the Cebu Shell Daktari strikes!
<[log in to unmask]>
01/05/05 03:58 AM
Please respond to
Conchologists List
> However, mollusks are relatively unusual in having many kinds that
>are normally distinctly asymmetric. Many forminifera have
>snail-like coiled shells; these can be sinstral or dextral, too.
Foram handedness is temperature-controlled, with no genetic
component, and is unrelated to gastropod coiling. Indeed, the
organisms (currently in kingdom Protists, so they are not animals or
"creatures") themselves are basically "amorphous" blobs of protoplasm
& organelles. I wonder how they manage to secrete such regular and
beautiful shells?
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