Dear all,

As Andrew points out, the expectation is a curve which rises sharply
and then tails off. Since there is rarely enough time to exhaustively
collect and identify every specimen it is not surprising that
ecologists have devised various ways of estimating species diversity.
If anyone is interested, the friendliest book on the subject I know
is:

Magurran, A.E. (1988) Ecological Diversity and its Measurement.
Chapman & Hall.

From the replies coming in, it looks as if conch-l collectively has
some interesting data on the subject.

Liz



Dr Liz Somerville
Sub-Dean (Academic Affairs)
School of Biological Sciences
University of Sussex
Falmer
Brighton
BN1 9QG

Tel: 01273 877460
internal no: 7460

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