Re: Haldane's dilemma

Stephen Jones (sejones@ibm.net)
Tue, 13 May 97 06:11:33 +0800

Adrian

On Tue, 29 Apr 1997 09:25:49 -0700, AdrianTeo@mailhost.net wrote:

>WE>ReMine had also asserted that Haldane's dilemma could be seen in
>the operation of evolution simulations. Upon this point, I
>challenged ReMine to name the simulation which showed the
>difficulties of HD, to specify how such difficulties were
>recognized or quantified, and basically to have the whole issue put
>to empirical test. I offered to modify an existing program to use
>the "soft selection" described by Peters and Colby, and then we
>would see if the problems went away as Peters and Colby asserted,
>or remained as ReMine asserted.

SJ>Would you mind if I sent a copy of your comments to Walter to
>give him the right of reply? I have no guarantee he will reply,
>since my past attempts to lure him back to the Reflector have
>failed.

AT>Although I would still encourage you to contact Walter about this,
>I would like to add that I did ask him about the program recently.
>He stated very clearly that he did in fact post on t.o. that the
>source for the simulation is described in his book. So I went back
>and checked his book. On chapter 8 on Haldane's dilemma, from
>pp.231-236, the simulation is described. Since Dawkins' original
>program is claimed to be lost, a simulation by David Wise of the
>National Center for science Education was used, and Walter claims
>that it is functionally equivalent. Given the same parameters, the
>program yielded similar results. Walter goes on to dscribe problems
>with the parameters, and according to the book, using
>non-determinstic mutation and a reproduction rate of N=6, the
>>simulation goes into error catastrophe. By exploration, Walter
>found that the mutation rate that produces the fastest rate for
>evolution was 1 in 56. Given this, the average time it takes to
>reach the target is 1663 generations. This figure is still pretty
>optimistic, since the simulation assumes a number of things which
>favors evolution.

Yes. This was my point, also. But I will probably contact Walter,
if for no other reason than to say hello!

>WE>ReMine did not produce the name of the simulation that he had
>claimed showed the problem, nor any indication of how one
>recognized the problem in a simulation. It seems to me that he
>missed a great opportunity to try out his idea.

SJ>ReMine actually names one in his book, ie. Dawkin's "Methinks it
>is like a Weasel" simulation:... (ReMine W.J., "The Biotic Message,
1993, p236).
>
>ReMine's failure to produce this simulation is hardly his fault -
>Dawkins' claims he has lost it ... Dawkins, 1991, personal letter)"
>(ReMine W.J., "The Biotic Message, 1993, p235).

AT>Does anybody know of anyone at the National Center for Science
>education, or know of any way to get a hold of the program? I tried
>searching the web for the home page, but was unsuccessful.

ReMine mentions one:

"David Wise, offers a simulation52 that functions
identically to Dawkins' original.

[...]

52 David Wise's simulation, for the IBM compatible PC under DOS, is
circulated by the National Center for Science Education-a major
anti-creation organization."

(ReMine W.J., "The Biotic Message", 1993, p235)

Also, in the back of The Blind Watchmaker there is an advert for
Dawkin's Biomorph program, plus another called "Survival of the
Fittest". It is sold by:

SPA
PO Box 59
Leamington Spa CV31 3QA
Ph. 0926 422959
Fax 0926 422148

In the exchange in Commentary of September 1996 between David
Berlinksi and his critics, Randy Wadkins mentions a Dawkins' clone
(computer program that is!) written in BASIC:

"...while Richard Dawkins was unable to write a computer program
that simulates evolution, scientists more adept at programming have
indeed been able to do just that. The natural-selection algorithm in
Keen and Spain's Computer Simulations in Biology generates the
phrase BASIC BIOLOGICAL MODELING IS FUN from a string of
random letters, based on Dawkins's suggestions." (Wadkins R.,
"Denying Darwin: David Berlinski and Critics", Commentary,
September 1996, p10)

For the record, Berlinski's response was:

"When I observed that Richard Dawkins was unable to write a computer
program that simulated his linguistic thought experiment, I did not
mean that the task at hand was difficult. It is impossible. Mr.
Wadkins commends the discussion in Keen and Spain's Computer
Simulation in Biology as a counterexample; its no such thing. What
Keen and Sain have done is transcribe Dawkins's blunder into the
computer language Basic. Here are the steps they undertake. A
target sentence is selected- BASIC BIOLOGICAL MODELING IS FUN. The
computer is given a randomly derived set of letters. The letters are
scrambled. At each iteration, the computer (or the programmer)
compares the randomly derived sequence with the target phrase. If
the arrays-sequences on the one hand, target phrase on the other-do
not match, the experiment continues; if they do, it stops.

There is nothing in this that is not also in Dawkins, the fog spreading
from one book to the next. The experiment that Keen and Spain conduct
is successful inasmuch as the computer reaches its target; but
unsuccessful as a defense of Darwinian evolution. In looking to its target
and comparing distances, the computer is appealing to information a
biological system could not possess.

This point seems to be less straightforward than I imagined, so let me
spell out the mistake. Starting from a random string, suppose the
computer generates the sequence BNDIT DISNE SOT SODISWN
TOSWXMSPW SSO. Comparing the sequence with its target, it
proposes to conserve the initial "B." But why? The string is gibberish.
Plainly, the conservation of vagrant successes has been undertaken with
the computer's eye fixed firmly on its future target, intermediates selected
not for what they are (gibberish, after all), but for what they will be (an
English sentence). This is a violation of the rule against deferred success.
Without the rule, there is nothing remotely like Darwinian evolution.
What the computer has in fact done is to match randomly selected items
to a template, thus inevitably reintroducing the element of deliberate
design that was banished from the Darwinian world." (Berlinski D.,
"Denying Darwin: David Berlinski and Critics", Commentary, September
1996, p31)

God bless.

Steve

-------------------------------------------------------------------
| Stephen E (Steve) Jones ,--_|\ sejones@ibm.net |
| 3 Hawker Avenue / Oz \ Steve.Jones@health.wa.gov.au |
| Warwick 6024 ->*_,--\_/ Phone +61 9 448 7439 (These are |
| Perth, West Australia v my opinions, not my employer's) |
-------------------------------------------------------------------