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From: ward@hao.UUCP (Mike Ward)
Newsgroups: net.origins
Subject: Re: Innocent Question
Message-ID: <1532@hao.UUCP>
Date: Fri, 10-May-85 08:54:44 EDT
Article-I.D.: hao.1532
Posted: Fri May 10 08:54:44 1985
Date-Received: Mon, 10-Jun-85 05:46:24 EDT
References: <1534@aecom.UUCP>
Distribution: net
Organization: High Altitude Obs./NCAR, Boulder CO
Lines: 13

> I was just wonderin'... If evolution happened in abrupt
> changes, wouldn't two animals have to undergo the same
> (or a similar) change? I mean, if in each step the new
> species can't breed with the old, we would need two of
> the new species in order to get something started. 

I think you misunderstand the meaning of the term 'abrupt' in
this context.  I know of no scientist who thinks that new species
evolved in a single generation.  The abruptness that seems part
of Punctuated Equilibrium is only abrupt when viewed from the
perspective of geological time.  There is every indication that
such changes take *at least* many thousands of years.  When charted
on a four billion year scale, they look abrupt.