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RE: Occam's Bull



On Thu, 12 Dec 2002 22:10:25  
 MariusRomanus wrote:
>Well... It's good to see that you agree... But... What was it that you 
>disagreed with again??? Oh yeah... This: 
>
>Steve Brusatte writes: >> Okay, fine. Agreed.  But, what is your 
>recommendation to better this problem?......... This method isn't perfect, but 
>what is your alternative? I don't have one. << 
>
>That is so odd... Where was YOUR suggestion again?... I must have missed it.   
> Oh yeah... You didn't have one... But you sure felt the need to point out 
>that I didn't have one either... even though I never said we needed a 
>completely new >method to begin with. 

I might have come across as a little hostile (which was not my intention, as 
I'm not a hostile person :-), but my major point was this: we know cladistics 
isn't perfect and isn't completely objective, but we don't have a better method 
at this time.  Therefore, there is no reason to keep attacking it.  I know that 
Kris basically feels the way I do, but sometimes I get tired of these attacks 
against cladistics.  Looking back at Kris' original words, what I at first 
thought was more of an attack really wasn't.  But, if somebody is going to 
really attack cladistics, I would appreciate an alternative solution.

I don't have an alternative solution.  Hopefully someday one might be 
developed.  But, there will always be subjectivity and unimpartial facts and 
personality differences because humans do science.  My suggestion is for 
scientists, especially professionals, but also interested and knowledgeable 
amateurs, to rigorously look at matrices and analyses presented in papers.  
Look at what the character codings are and if these codings are explained.  
Check them against other matrices.  See what characters are being used, reused, 
and changed.  This does, understandably, take a lot of work.  Some people 
dedicate their lifetimes to this sort of thing.  But, science will always be 
subjective to some extent, and rigorous research, discussion, and examination 
of one's own ideas are the best method to ensure less subjectivity.

>But hey... It wouldn't be me if I didn't offer my two pennies worth now would 
>it?... So, since you asked, here is just a mild suggestion... 

Thanks!  I appreciate it.  I'm glad to see that you have a suggestion, and I 
wish that others who bring up problems with cladistics would follow.  Since, 
technically, I agreed with many of the faults you found with the method, my 
suggestion is what I wrote above.  

>Let's  Remember to run the traits with the reversals-way of, true to reality, 
>para and covergent etc, way that evolution goes about its normal, every day 
>business. 

I'm not quite understanding you here.  Are you advocating that we assume 
reversals and code them that way?  I hope not, as I don't see this being a good 
method at all...  Sure this is normal evolution, but this assumption is much 
more subjective than cladistics.

>Oo! Oo! And lets not forget to take development into account... As in the now 
>you see it... now you don't way, that traits develop in an animal. 

Agreed!  However, this is too tough to do with extinct animals, obviously.  
Even when we have embryos it is too difficult, as we only have bones (and 
perhaps skin imprints) and no record of how these embryos develop.  But, for 
cladistic studies of extant organisms, yes, development data is crucial (in my 
opinion).

>Let's also not forget isolated mutation in either individuals, or in small 
>populations, that are simply odd ball events. Digit variations and wormian 
>bones... just to name two that we see all the time... come to mind. 

Sure...but, again, with fossil specimens this is hard to sort out.  We might 
only have one specimen of something, so it is impossible to tell whether or not 
its apomorphies (or potential synapomorphies shared with other taxa) are really 
just odd ball events.  It is much easier with things like bone beds, though.

I appreciate your suggestions!  Again, apologies if I came across as too 
hostile. :-)

Steve

---
******************************************************
Stephen Brusatte
Geophysical Sciences
University of Chicago
Dino Land Paleontology-http://www.geocities.com/stegob
******************************************************


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