Re: Waimanu

[jrc <jrccea@bellsouth.net>]

----- Original Message ----- 
From: "john bois" <jbois@verizon.net>
To: "dinosaur" <dinosaur@usc.edu>
Sent: Saturday, May 20, 2006 11:57 PM
Subject: Re: Waimanu



> My understanding is that large species (w/low reproduction rates, etc.) 
> are
> more prone to extinction.  This would seem to require a more or less
> constant refuelling from among the smaller species from the same taxon.

Or replacement speciation by larger competitors.  You don't have to be small 
to speciate (is that a word?).  I doubt that any pterosaur species was large 
enough for size-related problems to come strongly into play anyway.

> This fuel may not have been present.for pterosaurs--if true they may have
> been doomed, period.

Why would that fuel not have been present?  Albatrosses could survive at the 
size of the bigger pterosaurs (if their wings were structurally capable of 
reaching those spans, and if they could solve the launch problem at those 
higher weights).


As a personal opinion, what whacked the pterosaurs, was a period of at least 
a few weeks with weather conditions that were unsuitable for soaring, world 
wide.  During that period, the few birds that survived relied on flapping 
flight.

> Also, please excuse my Yogi Bera moment: "ratchet of no return".

I didn't notice (may have been having a Yogi moment of my own).