Having shelled one area near my home for about 15 years, I noticed when I
prepared an exhibit of shells from that area recently that the molluscan
composition of the area has changed. Some species I used to find often I
now find seldom, and some species I never used to find I now find.
This is, of course, different than the record with fossil species; those
are there and won't move around. Living molluscs can colonize new areas or
be wiped out of old ones. The habitat can change, so the species
represented will change. I know the habitat at Peanut Island has changed
over the years. There used to be lots of largish rocks starting at shore
and going out into the water quite deep; the last time I was there (several
years ago) most of those rocks had been silted under the sand. This is a
natural phenomenon and naturally the shells I found were different.
Peggy
Visit my website at http://www.shelltrips.com
Peggy Williams
Shell Elegant
PO Box 575
Tallevast FL 34270
(941) 355-2291
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