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Re: Evolution programs (was: Reevolving bones)



>Jonathan R. Wagner wrote:
>
>[big snip related to the never-ending cladistic wars]
>
>>
>> Dinogeorge wrote:
>> >Mickey Rowe, and I suggested the following experiment:
>> >Using a computer program that simulates evolution
>>         Can we really do this? Forgive, but I rather
>> thought that if we could do this, I wouldn't have to
>> go to grad school.
>
>Good news, you can leave grad school!
>
>Evolution Programs (EPs) are widely used (I can give you
>hundreds of references). They consist on what is called a


<Another big snip>

>have no problem in calling that set of characters a "dinosaur
>model" just to stay on topic in this list.


I have often thought of this kind of experiment but it needs a further
filter. In order to mimic the effects of fossilisation and the incomplete
nature of the fossil record, once the complete evolutionary tree has been
constructed, 99.9 percent of the individuals in the tree are elimimnated.
There could be some fiddling here to mimic the likelyhood of fossilisation
(ie reducing the change of fossilisation for a terrestial species as
opposed to that of a shallow marine species). Further, to more accurately
mimic the nature of the vertebrate fossil record, only 10% of the surviving
species are represented by complete character sets and the remainder are
randomly divided into 9 groups. Each group has a further 10% of its
characters removed. Hangon, that means that there will be one group with no
characters (oh well, I'm sure you get the idea). One final filter would be
that the "geological time" of an organism or species should also be
recorded.

The net effect of this will be that, instead of a nice data set of all
characters for all organisms, there will be character sets of varying
completeness for only a few organisms. This data set is then presented to a
number of systemacists to evaluate and attempt to reconstruct the original
tree.

Sounds like fun or what!

Cheers,

Paul


Dr Paul M.A. Willis
Consulting Vertebrate Palaeontologist
Quinkana Pty Ltd
pwillis@ozemail.com.au