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From: ethan@utastro.UUCP (Ethan Vishniac)
Newsgroups: net.origins
Subject: Re: Kinds
Message-ID: <534@utastro.UUCP>
Date: Fri, 14-Sep-84 16:35:13 EDT
Article-I.D.: utastro.534
Posted: Fri Sep 14 16:35:13 1984
Date-Received: Tue, 25-Sep-84 02:31:10 EDT
References: <286@uwmacc.UUCP>
Organization: UTexas Astronomy Dept., Austin, Texas
Lines: 34

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     A while ago, in a fit of cynicism, I offered the following
definitions:
     Variation within kinds - changes in the characteristics of
     any population of animal or plant which are well documented
     in the historical record.

     Variation between kinds - all others

In the absence of any definition of "kind" other than "sharing
a common ancestral population" I seem to have been more accurate
than I thought.
  
     There is a recurrent problem in biology about the definition
of species which other people have mentioned, i.e. what is a "species"
anyhow?  "Everyone" knows the answer to this in the sense that observers
from different cultures will, in analyzing a given ecosystem, divide
up creatures into the same sets of species. (I think this comparison
has actually been done for American ornithologists and Papuan headhunters).
However, inevitable ambiguities arise.  From an evolutionary point of
view this is normal.  Speciation occurs as isolated breeding groups
develope incompatible habits and biochemistry.  There will always
be examples of groups that are somewhat distinct, have slightly
different ranges or habits, and do not *normally* interbreed.  Many of
them may never become truly distinct species.  From a creationist point
of view this ambiguity is more irritating.  The definition suggested
by Paul Dubois (I know he didn't make it up, but I forget his source),
gets around this problem but only by making variation between "kinds"
impossible by definition.

                         Ethan Vishniac