Newsgroups: sci.bio
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!snorkelwacker.mit.edu!news.media.mit.edu!media-lab.media.mit.edu!minsky
From: minsky@media-lab.media.mit.edu (Marvin Minsky)
Subject: Re: Coelocanth and evolution: x
Message-ID: <1991Jun13.220310.16428@news.media.mit.edu>
Sender: news@news.media.mit.edu (USENET News System)
Organization: MIT Media Laboratory
References: <472.28511bf9@mbcl.rutgers.edu> <34@tdatirv.UUCP> <476.2856b24b@mbcl.rutgers.edu>
Date: Thu, 13 Jun 1991 22:03:10 GMT

kliman@mbcl.rutgers.edu remarked,

>The original question posed - can a species remain unchanged for
that long - is fun to think about.

Consider that all we know about those "living fossils" is that their
external appearance hasn't changed very grossly.  However, a good
proportion of the genome goes into the brain structure and
connections -- and we cannot see much of that.  Now it seems to me
that there is a nice opposition here: any gross skeletomuscular change
has a central nervous price, because the reflex systems and higher
level instincts need reprogramming.  (That is, to the extent that the
local learning systems cannot easily adapt.)  And conversely, the less
superficial change, the easier to evolve new behavioral adaptations.  

So, to first order, the more the Coelocanth seems the same -- outside
-- the more different it would be -- inside!

Of course, that wouldn't be true to second order.  Because new
behavioral abilities brings with it new possibilities for changing