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Re: flying Archie

Well, my original point apparently stands; it is at least OK to use terms like 
"inferior" and "superior" relative to quantifiable traits/processes. I mention 
this only so that everybody, including me, is reminded that the topic has 
changed somewhat. Might even delete the foregoing before sending (or not).

The points about what constitutes evolutionary success/superiority are very 
interesting and well taken. I would like to pose questions based on the 
following assumptions: 1). the ancestral croc gave rise to a number of 
long-lived species. 2). the ancestral (modern) bird gave rise to a larger 
number of species of shorter "lifespan".  

The genome of the ancestral bird, _as it exists today_,  outranks the croc's by 
measures such as morphological/behavioral complexity/diversity, and (I posit) 
the potential for the generation of new forms to exploit both new and old 
environments. Ignoring the fact that the final croc and the final bird are 
likely to die at the same time (geologically speaking), is the croc more 
successful that the bird? And if the timespan between the "first" and "final" 
croc is larger than between "first" and "final" bird, does that mean the crocs 
have won?

Or, within birds, is the ancestral osprey (old species) more successful than 
it's "clutchmate", that eventually gave rise to the cardinal (young species), 
among many, many others?

Couple more comments below.


----- Original Message ----
From: Michael Habib <mhabib5@jhmi.edu>
To: DINOSAUR@usc.edu
Sent: Sunday, September 24, 2006 3:16:45 PM
Subject: Re: flying Archie

> 2. Maybe not morally superior. Relative to speciation, passerines are 
> definitely superior to ratites or penguins or birds of prey.
> Don

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 
Absolutely. Fun, though. And sometimes necessary.
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). 
Heh. That is guaranteed, especially in this cyber-world. 
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.
Point taken, but see above.


--Mike Habib