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Re: Son of response to Nick Pharris



> for nest sites by their flying cousins), two-legged.  That this
> is still a defunct strategy is shown by yet another pattern:
> there are none of these creatures alive today where there are
> mammals.  I am sorry, there are some on islands (N.Z., Hawaii)
> but introduced mammals are driving these into rapid extinction. 
>      Perhaps close-cover _was_ part of the dinosaurs' fundamental
> niche, but thanks to the mammals (and others) their realized
> niche was the open field.  And it was there that they had to try
> and cope with their problem: they could not hide their eggs!
>      I'm not sure about gruiforms or galliforms, but the quail
> and grouse also lay eggs on the ground.  But they are things that
> a dinosaur couldn't be: they are small (see above arguments) and
> they can fly.  You might argue that flying has nothing to do with
> laying.  Again, I would say that whether an animal is successful
> or not depends upon the cumulative effect of predation at various
> stages of its life.  Quail and grouse suffer intense egg
> predation.  

     First of all, New Zealand animals evolved without the threat of egg 
eating mammals, wheras dinosaurs would have had to deal with this 
problem and might have develeoped defenses.  Its not fair to say that a 
small dinosaur could not have evolved a defense against egg eaters because 
isolated and protected populations didn't have this problem and evolved 
accordingly.
    Your argument for why there were no really small dinosaurs implies 
that this was due to the threat posed to the eggs.  What difference does 
it make if the parents get away if a next generation doesn't have a 
chance of getting started?  As you say, small ground birds suffer heavy egg 
mortality, but this has not stopped them.  Why should it have stopped 
similarly sized dinosaurs?    
     How does a quail or grouse's small size help them?  You say that 
dinosaurs could not be small because they couldn't defend thier nests, 
but then seem to imply that quail and grouse being small HELPS them 
somehow in this regard.

> extinction were like the fishermen of New England.  In this
> Tragedy of the Commons, the fishermen destroy their livelihood
> EVEN THOUGH THEY KNOW THEY ARE DOING IT!!!!!  The fish probably
> would have been alright had the fishermen not developed fish
> radar, etc.  But unable to respond to this new technology, they
> succumb.  Dinosaurs, I submit, due to their body plan and their
> eggs, could not respond to the new technologies coming off the
> mammal and bird lines.

     Using humans and human behavior as analogues for other parts of the 
animal kingdom is always a bad mistake.  We are the exceptions to EVERY 
rule.  Fish finder technology, fishing nets, etc...popped up a lot faster 
than natural selection could make a better predator, so naturally the 
fish aren't going to have time to evolve appropriate defenses 
(radar absorbing scales and net cutting appedages, presumably).  
Also, as a species we go with equal proficiency after a wider range of prey 
than probably any predator species that ever lived, and so can cause 
extinctions on a scale that no other single predator species ever could.  We 
don't play by the same set of rules that other animals do, and should be 
extremely careful to what extent we anthropomorphize other species.
     You note improvements in the mammal design, but don't seem to think 
that dinosaurs were equally capable of evolving effective defenses to egg 
eaters.  

     By the way, off the subject....I think the silouette of a guy on a 
surfboard looks about as much like a seal as a frog looks like a weasel.  
I think it is at least as likely that shark attacks are taste tests rather than 
mistaken idenity.  Its strange and unfamiliar, but it apparently alive 
and hasn't done anything aggressive, so why not try a nibble?  Its probably 
edible.  Garbage like horse heads and tires have been found in shark 
stomachs, but I don't think anyone will argue they thought it was a seal.

LN Jeff
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"My goal to conquer the world failed."
"I know how you feel.  I had a goal to grow a mustace once, but it was 
out of my reach.  I mean figuratively out of my reach.  I could still reach up 
and touch my lip, but you know."
"Right, but back to me..."
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