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WHAT'S GOING ON?



<<Although I don't like the Feducciaries and their disdain for cladist
analysis, I also don't like the strict cladists and their disdain
for selective eclectic classification.>>

Actually Ernst Mayr is a bigger (and probably more effective) critic of cladists than Feduccia will ever be.

What is selective eclectic classification?  (Sounds like an oxymoron.)

<<When strict cladists respond in this way, and infer that someone
doesn't know the difference between dinosaurs (sensu stricto) and dinosaurs (sensu lato, i.e., including birds), I think they hurt not only
cladistic classification (which I use up to a point), but also cladistic
analytical methods (which I find very valuable).>>


How? The driving force of life is evolution. To exclude birds from the rest of dinosaurs is not an evolutionary perspective.

<<This insistence that the rest of world recognize their terminology,
and making fun of those who don't distinguish between dinosaurs (sensu stricto) and a cladistic dinosauria (sensu lato), will only backfire, and I would discourage such tactics. I could care less if it turns people off to strict cladistic classification, but when it casts a cloud over cladistic analytic methodologies, then it really starts to irritate me.>>


Without getting myself involved in whatever matter you are discussing let me give you some historical perspective on cladistic vs. Linnean (or whatever) classification:

As I said above, cladistic classification is grounded in evolutionary thought, where everything shares a common ancestor at some point on the tree of life. Defining groups by their common ancestry is not only convenient, it makes sure that we will not be excluding organisms from the group in the future, it is also evolutionary. We have a more accurate picture of life and how it changed because rather than vaguely tracing ancestries and lineages on the Linnean chart (or whatever), we can identify where, for example, birds and cabbages had their last known common ancestor. We can't do this as well in Linnean (or whatever) classifications.

Linnean classifications were popular for a couple hundred years. The reason they were so popular for the first hundred years of their existence is because they lent themselves to the predominantly non-evolutionary classifications of the 18th and 19th centuries. Birds and reptiles sat on seperate ends of the Linnean chart seperated by a gulf seemingly larger than any systematist could bridge. Essensialism (going back to Plato), archetypalism, and typology, non-evolutionary theories of thought were easily accomodated by the Linnean system. Since relationships weren't inferred by Linnean taxonomy, essensialist, non-evolutionist, systems such as typology could be utilized to their full potential; there would be no muddy areas in the chart where reptiles changed into birds, the basic types (the very root of the word typology) would never change. The very face of nature, that is evolution, would be ignored.

Linnean classification could be converted over to evolutionary perspectives, but things get confusing:

Say I have a small proto-animal, lets call it _Tyler durden_. It is the sole member of the family Tyleridae. Now, we know that this animal is the closest thing to the Kingdom Animalia; it is *almost* an animal, but not quite. One of the first animals is _Marla singer_, seperated from _Tyler_ by being in the rank of Kingdom instead of Family. From the cladistic perspective, _Tyler_ and _Marla_ share a common ancestor but _Tyler_ is excluded from the group _Marla_ is in by the fact that she has an ancestor that _Tyler_ does not have. On a Linnean chart, such relationships are difficult to convey because they are not inherently evolutionary, cladistic classifications are by their nature built to convey evolutionary relationships. This is why they are so successful; their structure is not a simple catalouge, they are a tree showing the relative evolutionary relationships of one group to another (and so on). Cladistic trees do not give direct ancestor-descendent relationships on the large scale, they can only give more vague relations because human scientists were not living back 600 million years ago to witness the birth of animals; the only way we can be scientific is by not explicitly positing ancestor-descendent relationships, and letting the trees speak for themselves. Only with greater magnification on the branches of the tree (and perhaps the physically impossible time machine), can we tell ancestor-descendent relationships. Until then, we have to be scientific and say only what we know for sure.

<<Making fun, explicitly or implicitly, of those who don't specify "non-avian dinosaurs" should realize that it is not longer humorous, and the point they may trying to make is counterproductive. Alex was looking for information, and all he got was implicit criticism, and I don't think this is helpful.>>

I haven't read the message that read up to this, so I won't comment on it.

Anyway, saying "non-avian dinosaurs" is the scientfically accurate way of describing what classical dinosaurs are. By not including birds within dinosaurs we are going back to the days of typology where birds were seperate from everything else on the planet (as were dinosaurs). We most express things they way that they are, evolutionarily. To exclude birds from dinosaurs, not being in keeping with the evidence at hand and certainly not looking at it evolutionarily.
Matt Troutman
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