[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Yet more on dinosaur quad climbers

On Sat, Jul 13, 2013 8:35 AM EDT David Marjanovic wrote:

>Collected thoughts...

>-- The GFTR hypothesis still needs a way to get from gliding to flapping.

As do all trees-down scenarios -- braking motions, ground-based fighting in 
it's various forms, Jason's point that even weak flapping would be helpful in 
regaining the tree at the end of each forage cycle -- just a few possibles.

Boehm's ridgesoaring deserves more thought, IMO. A GFTR glider living on the 
edge of a coastal dune environment seems like a fertile field for rational 
speculation to me.

 I'm also not sure if a glider rather than a parachuter would really result, 

Why not? Extended horizontal reach is a handy talent whether acquiring food or 
escaping predation. And incrementally useful.

>why a perching foot or some other such adaptation wouldn't evolve pretty soon 
>after selection pressure for roosting set in. 

In the absence of conservation by terrestrial foraging, you mean? 

>-- Weird shit happens. The argument from personal incredulity is a logical 
True!  But 10^6 is still 10x more probable than 10^7.
>-- The ability to retract the head into the shell evolved twice independently 
>in turtles, and not very soon. *Proganochelys* and *Meiolania*, to mention 
>just two, were clearly incapable of any such retraction.

Saw a 25 lb Alligator Snapper charge a dog once -- then it charged me.  That 
big head and series of forward hops really gets your attention.