Re: Paedomorphosis ( Re: BARYONYX' CLAWS )

["tons" <tons@netside.com>]

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> From: Dinogeorge <Dinogeorge@aol.com>
> To: m_troutman@hotmail.com; dinosaur@usc.edu; darren.naish@port.ac.uk
> Subject: Re: Paedomorphosis ( Re: BARYONYX' CLAWS )
> Date: Saturday, April 11, 1998 4:22 AM
> 
> In a message dated 98-04-09 21:34:53 EDT, m_troutman@hotmail.com writes:
> 
> << Basically, the penguin, auk, and plotopterid "flippers" are 
>  modified wings. They use their wings in a manner similiar to volant 
>  birds. These birds still have a functional flight apparatus, but where 
>  they are different from volant birds is in their forelimbs structure, 
>  which is more robust. Penguins, auks, and plotopterids are essentially 
>  still fliers, just in a water medium.>>
> 
> I wish you'd stop calling "swimming" flying. It doesn't help your
argument a
> bit. These are birds that have exapted their flight anatomy for the
purpose of
> swimming through water. In becoming more efficient swimmers, they lost
the
> ability to fly through the air. You noted in a previous post that there
may
> have been a transitional stage in which the wings were used both for
flying
> through the air and swimming through the water. With this I can agree.
> Likewise with small, arboreal theropods, there was probably a stage in
which
> the forelimbs were used for grasping and climbing and for some kind of
flying.
> In later theropods, the grasping uses prevailed; in later birds, the
flying
> uses prevailed. Why is this incredibly simple, obvious, and natural idea
so
> difficult for you to accept?
> 
Animals move from one point to another by locomotion.  We name certain
methods for convenience and give different mediums they locomote in names
as well.  These are matters of semantics for us.  

I agree (for what that's worth) with George concerning comparing some
swimming birds and flying.  Penguins do not fly since by definition flying
is locomotion thru the air as swimming is locomotion thru water.  He also
makes a point concerning the loss of the forelimbs ability to fly.  They
have (probably) evolved from flight to swimming.  There are birds that do
both fly and swim.  I have not looked whether there are any differences in
the mechanics of the shoulder girdle and forelimb performing these two
functions.  Therein lies others points about "flying" thru water.  Flying
fish probably do fly since they glide for fairly long distances.  Do
whales, dolphins, etc "fly" when they locomote out of the water?  Probably
not since this would be analogous to my jumping in the air or off a
building.  I'm not locomoting but falling with or without grace.

I don't know where or how it started nor which group gave rise to flight,
but birds are here so it did.  George made an interesting comment recently
about very small theropods giving rise to animals capable of flight.  I
thought it was an interesting comment.