A malacologist told me he had collected "live Siphonaria and
Onchidella from 1000 m living on algal holdfasts with climax bathyal
algae-eating limpet colonies". This says something about the limits
of a species' ability to live successfully; it also says something
about the larvae of that species, and they conditions in which they
settle as opposed to that in which they COULD live if they settled
outside the normal preferences.

I have also observed behavior of the introduced landsnail Candidula
intersecta when coming across a puddle in a depression on the surface
of limestone blocks after rain: the snails just crawl throught the
puddles.
--
Andrew Grebneff
Dunedin
New Zealand
Fossil preparator
Seashell, Macintosh, VW/Toyota van nut
� Opinions stated are mine, not those of Otago University
"There is water at the bottom of the ocean"  - Talking Heads