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Re: flying Archie
2. Maybe not morally superior. Relative to speciation, passerines are
definitely superior to ratites or penguins or birds of prey.
True, though I would suggest that 'superior' is a poor term in
reference to speciation. There is a tendency to think of clade size as
a measure of "success" in lineages. It is not a bad measure of such
things (though trying to measure success in the first place is pretty
subjective), but it is not the only one. And, in fact, I do not think
it is the best. The main reason that there are 5,000+ species of
passerines is because they isolate easily. While that is interesting
and important biologically, I (personally) don't see isolation tendency
as a measure of "success" (others may disagree, of course). Geographic
range size is probably more important if speaking of resistance to
extinction, and population size better indicates the ability to replace
losses or decrease mortality. At the broadest scales, species
durations seem just as good a measure of "success" as clade size.
Measuring the tendency to form isolates strikes me as very important,
but not a measure of adaptive "superiority", at least by the way I tend
to view adaptive traits.