human origins

John Grehan jgrehan at TPBMAIL.NET
Thu Jan 22 18:58:23 CST 2004


In further response to Richard:

At 02:45 PM 1/22/04 -0600, Richard.Zander at MOBOT.ORG wrote:
>Lotsa good stuff to respond to here. First,re conflicting data, if the data
>are attributable to random generation of shared traits within a confidence
>interval, then there is really no data, and no data conflict. It's like
>flipping a loaded coin once then saying it is loaded on the side the comes
>up (once).

Maybe. The question is whether or not that may be applicable to the
human-orangutan question. I'm not in a position to argue the case against
this kind of criterion (which some may rightly consider a weakness in my
position, but then that's just a fact of life).


>Of course something may be statistically reliable and be wrong. The question
>is always, however, at what level of reliability will one act on the theory
>given the risks of being wrong. We need a high level of reliability to act
>(e.g. base other research on the phylogenetic theory, like guiding
>biogeographic studies) give that we are betting our science.

What constitutes a 'high level of reliability' depends on what position one
takes on setting the necessary criteria, and there are no universals for this.

>I don't think there is a question of "belief" in darwinian selection as a
>pretty good explanation. Lakatos I think pointed out that in scientific
>studies one doesn't have to prove over and over again certain basic theories
>when one is doing particular research based on those theories.

I have no dispute with this. The results of the research in terms of
theoretical and empirical progress may be more important.

>If you, John, have an alternative to Darwinian explanations then you
>should present these
>in a forum in which they contend with Darwinian theory directly, not bring
>them up in derivative discussions.

If I accepted Richard's authority on this I would agree, but since I do
not, I won't. Anyway, much of what is said on TAXACOM is Darwinian theory.
If its ok for Darwinians to assert their position why is it wrong for
non-Darwinians to assert theirs?

>Maybe you are right, but we are not
>comparing directly alternative theories in this forum.

I was not aware of this being TAXACOM policy. Is Richard correct?

John Grehan




>-----Original Message-----
>From: John Grehan [mailto:jgrehan at sciencebuff.org]
>Sent: Thursday, January 22, 2004 1:06 PM
>To: Richard.Zander at MOBOT.ORG; TAXACOM at LISTSERV.NHM.KU.EDU
>Subject: Re: [TAXACOM] human origins
>
>
>Some (possibly naive) responses to Richard:
>
>At 10:57 AM 1/22/2004 -0600, Richard.Zander at MOBOT.ORG wrote:
> >Well, hang on a minute there. The molecular data are commonly sufficient to
> >allow statistical tests of reliability but morphological data are generally
> >not. It isn't just "genetic sequence similarity" to the exclusion of
> >morphological data.
>
>The trouble occurs when one lot conflicts with the other to give two
>totally different patterns of relationship (in this case human-chimpanzee
>vs human-orangutan).
>
>Something may be statistically 'reliable' while still actually being wrong
>(i.e. all the stats in the world supporting the genetic similarity just
>confirms the genetic similarity - whether or not this similarity
>necessarily translates into a phylogenetic (spatiotemporal pattern of
>differentiation) similarity would seem to be another question.
>
> >Naturally, the presumption is that if random generation of parallel traits
> >in closely related but not sister lineages is not to be expected by chance
> >alone, one can assume shared ancestry of apparent sister taxa.
>
>Its certainly an assumption.
>
> >This is notexactly true since coadaptive traits associated with habitat
> >may also force
> >parallelism (pointed out by Landrum, Rensch and doubtless others) and thus
> >confound at least details of a cladogram.
>
>If one believes in natural selection as the driving force for taxogeny
>
>orphology and exons are liable to this problem, I believe.
>
>Whether or not one believes in this problem, the fact remains that
>orangutans have all these very prominent 'human' characters (or is it the
>other way around) including the very cognitive inclinations that underpin
>human technological thinking.
>
>
> >Statistcally impressive results from introns and junk DNA are hard to
> >explain away.
>
>Perhaps no harder than explaining all those morphological synapomorphies
>between humans and orangutans in this case.
>
>Cheers, John
>
>
>
>
> >-----Original Message-----
> >From: Ronaldo [mailto:ralperin at TERRA.COM.BR]
> >Sent: Thursday, January 22, 2004 4:06 AM
> >To: TAXACOM at LISTSERV.NHM.KU.EDU
> >Subject: Re: [TAXACOM] human origins
> >
> >
> >Hello John,
> >
> >Wednesday, January 21, 2004, 1:23:53 PM, you wrote:
> >
> >
> >
> >"So in conclusion the paper is fairly representative of what I am reading
> >  in general. The chimpanzee relationship is presented as a fact. It is
> >  based on the presumption of genetic sequence similarity being the whole
> >  truth of phylogeny, and morphological considerations are rendered almost
> >  a foot note with the consequent lack of rigor in any connection being
> >  substantiated between living humans and other apes and purported fossil
> >  representatives. "
> >
> >
> >  Fully agreed! John, here in Brazil we have the same situation with
> >  the primates in general. Just see the huge number of papers regarding
> >  "Phylogenetic" relationships among Neotropical Primates. I have to
> >  ask; "Phylogenetic" or Molecular (with no explicit criteria)
> >  relationships?
> >
> >
> >  Ronaldo Alperin
> >
> >JG> John Grehan
> >
> >JG> Dr. John Grehan
> >JG> Director of Science and Collections
> >JG> Buffalo Museum of Science
> >JG> 1020 Humboldt Parkway
> >JG> Buffalo, New York 14211-1293
> >JG> Voice 716-896-5200 x372
> >JG> Fax 716-897-6723
> >JG> jgrehan at sciencebuff.org
> >JG>
> >http://www.sciencebuff.org/biogeography/Panbiogeography/Panbiogeography-Gat
>e
> >.htm
> >JG> http://www.sciencebuff.org/HepialidaeGate.htm
> >
> >
> >
> >
> >
> >--
> >Best regards,
> >  Ronaldo                            mailto:ralperin at terra.com.br
>
>Dr. John Grehan
>Director of Science and Collections
>Buffalo Museum of Science
>1020 Humboldt Parkway
>Buffalo, New York 14211-1293
>Voice 716-896-5200 x372
>Fax 716-897-6723
>jgrehan at sciencebuff.org
>http://www.sciencebuff.org/biogeography/Panbiogeography/Panbiogeography-Gate
>.htm
>http://www.sciencebuff.org/HepialidaeGate.htm




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