parsimony/biology

[Kirk Fitzhugh]

Curtis,

No disrespect was intended, I assure you.

My concern is with what are patterns and what are explanations of those
patterns. There seems to be use of conflicting terms which I've been trying
to tease apart. For instance, if homology is the explanation of instances
of shared similarity (named features), as in "this feature x is due to
common ancestry," then we are not talking about patterns of homology. The
patterns that are observed are named properties of things. It is from the
recognition of named similarity (i.e., homologs) that we infer homology
hypotheses as individual explanations. My suggestion is that patterns don't
arise from homology or cladograms, but are explanations of patterns that we
summarize in the form of applying the same names to properties. I agree
with you that pattern recognition is fundamental, otherwise there is no
impetus for explaining. This does not, however, mean that cladograms are
the patterns in need of explanation, but are the explanations.

Sorry if my attempts have been perceived as "nonsense."

Kirk

At 07:40 PM 2/27/01 -0800, you wrote:
>At 09:06 AM 2/27/01, Kirk Fitzhugh wrote:
>>Wow, individual organism cannot be regarded as things?
>
>Good lord, don't you read? "And yet we are not forced to deal with them
>that way." And you'd be pretty embarrassed if you met me at a meeting and I
>only had one eye (thankfully, I still have two).
>
>>True, anything can be a pattern. But
>>do you really want to reduce cladograms to being nothing more than patterns
>>of intersecting lines?
>
>Uh, a pattern of shared homologies, perhaps? I guess I don't understand why
>the word "pattern" has you upset--it's not as if the pattern cladists had a
>lock on the word. Pattern recognition is the first step in many branches of
>science, something one does before looking for causality.
>
>As I mentioned, I haven't been following this thread closely, and if what I
>take as nonsense at face value actually has meaning in the context of the
>discussion, my apologies for intruding.
>
>
>--
>Curtis Clark                  http://www.csupomona.edu/~jcclark/
>Biological Sciences Department             Voice: (909) 869-4062
>California State Polytechnic University      FAX: (909) 869-4078
>Pomona CA 91768-4032  USA                  jcclark at csupomona.edu