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Re: A bit of cladobabble was Re: Cearadactylus - long, but with sausages

HP Marjanovic observed:
How do we know some characters are homoplastic? Because the animals are in
other clades. How do we know the animals are in the other clades? Because
putting them elsewhere would require much more homoplasy than we could
destroy that way...

When you say 'much more' you could be referring to characters by simple raw
count or to characters significant in distinguishing related taxa.  I think
you mean raw count, as in the last sentences of your para:
That's what's called parsimony, and it's why cladistic
analyses are done with such huge amounts of characters.

And yet, we're reading (with interest) about a dispute where certain
characters are stated to be more significant than others diagnostically.
It's this contrast between total number of characters and asserted
significant characters that creates the apparent contradiction.  Characters
which are not significant create the homoplasy, but how do we know they are
not significant?  This is not an example working simply from the
tree-with-the-fewest-steps model.
I'm sure there is an answer, but since I didn't see it, I asked.