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Re: synapomorphies not created equal
Ken Kinman wrote:
I've been thinking very hard about this, and I am still not convinced
that all synapomorphies are created equal. Some are "stronger" than others
no matter how long or big the evolutionary gap happens to be in which it
This is a slippery slope - and I'm quite frightened of what might lie at the
bottom of it.
I can foresee such an approach leading to a situation in which characters
are assessed as "strong" or "weak" according to how they fit a given
evolutionary scenario. Like: "I'm convinced tyrannosaurids evolved from
secondarily flightless birds, so any characters that contradict this
interpretation are weak because they are obviously giving a misleading
signal." (This is just an example; no malice is intended toward those who
actually hold the view that tyrannosaurids evolved from secondarily
The only anatomical characters I can see being justifiably termed as "weak"
are those which (for some reason) appear to be non-independent of other
characters. Some of these are in the process of being weeded out.
Currently, there's a lot of solid research going on to uncover the molecular
and development bases behind the expression of mammalian teeth. Certain
dental traits that have been traditionally coded separately in cladistic
analyses may really be iterations of a single character expressed down the
entire tooth row.
Now, if only InGen would hand over some of that dinosaur DNA of theirs we
could do some *really* fun stuff...
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