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Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)



Eric:

First, WAIR is Wing-Assisted Incline Running.  It doesn't specify what kind of 
incline - it could be a tree branch, or a rock ledge, or part of a river bank.

Secondly, your question concerning the use of the proto-wings to help capture 
insects has been proposed before, but not being used to provide a Bernoulli 
Effect suction, but to wave the bugs towards the mouth.  (Forgive me if I got 
this wrong, but I think John Ostrom first proposed it [It's been a long day, so 
far....]).

Hopefully, this helps,

Allan Edels
-----Original Message-----
Date: Thursday, September 04, 2008 6:11:45 pm
To: qilongia@yahoo.com
Cc: dinosaur@usc.edu
From: Erik Boehm <erikboehm07@yahoo.com>
Subject: Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)

> Humans possess pronating and supinating wrists, a highly
> mobile shoulder joint that can rotate the arm about its axis
> with a nearly 160 degree range of movement in three
> dimensions, and they can, to some degree, supinate the
> ankle.

no doubt we have climbing adaptations, but we lost others such as a prehensile 
foot and a prehensile tail. This point was in response to the statement made 
earlier:

> Archaeopteryx not only lacks those adaptations, but the phenotypic 
> trend of maniraptorans is to do the exact opposite 

My point is a trend away from an ability, does not mean that ability is no 
longer used.

What is WAIR?

I'm not saying archie climbed trees, especially not like a squirrel - just that 
the absense of the adaptations mentioned may not be relevant.
Furthermore, if archie or some hypothetical ancestor of archie did climb up 
something to glide, it wasn't neccesarily a tree, as I mentioned boulders and 
cliffs.

> The problem lies in several elements,
> including the apparent "half of a wing". What use
> is such a structure on the evolution towards flight?

Is holding its arms outstretched, and rapidly parting them to suck in a flying 
insect even plausible?
We know of many examples of feeding by sucking in the fluid surrounding prey, 
when the fluid i

Why can't a similar method work with air? it would give "half a wing" some use, 
and could then easily become a gliding surface.


--- On Thu, 9/4/08, Jaime A. Headden <qilongia@yahoo.com> wrote:

> From: Jaime A. Headden <qilongia@yahoo.com>
> Subject: Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)
> To: erikboehm07@yahoo.com
> Cc: dinosaur@usc.edu
> Date: Thursday, September 4, 2008, 2:05 PM
> Erik Boehm wrote:
> 
> <I think the perching adaptation that birds have is only
> of use once a minimum proficiency in precision flight is
> attained, and for the first examples of therepod flight, the
> absence of a reversed toe for perching probably is
> irrelevant in the arboreal vs cursorial