For those _really_ interested in cowries, I have explored the
range of possible labial tooth counts for a few of the Indo-
Pacific species of Cypraea with breeding populations in Hawaii.

By using the average labial tooth count and its standard deviation
from each of these four species, I have “inflated” their populations
to determine how big it would need to find a cowry with a labial
tooth count greater or smaller than the current range of labial teeth
in the samples that I am working with. A small table of possibilities
looks like this:

             my range of      # shells in   (“new” popul.)  to get 1
Cypraea       lab. teeth       my sample     # of shells    shell w/

helvola        11-20         2,600+         10,000       10 or 21 th
fimbriata      17-26           500           1,150       16 labial th
caputserpentis 13-22           300           5,000       12 labial th
poraria        15-23            90             450       14 labial th

So, to have a definite shot at finding a _Cypraea helvola_ with
either 10 or 21 labial teeth, the chances are about one in ten
thousand. (Yes, just like a lottery, or something.) To get one
of 10 labial teeth AND one of 21 labial teeth, the sample would
need to be nearly 20,000 shells! (That is, in Hawaii; populations
in your area may vary.)

Perhaps others have stats from cowries in their locales...

Aloha,

makuabob (a.k.a. Bob Dayle)

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