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

[Erik Boehm <erikboehm07@yahoo.com>]

There are environments today, mainly coastal, where a pure glider with a 3-4:1 
aspect ratio and less than a 4:1 glide can stay aloft for hours and travel 
miles. In the absence of competition, I have no problem imagining a pure glider 
using these conditions regularly, developing a more efficient wing, and over 
time, flapping.
All it requires is a coincident of geography to have a forest with gliding 
arboreal animals living in it, to be near a suitable ridge with a fairly 
consitent wind (most often due to the ocean or a large body of water at a 
fairly consistent temperature).
Many such places exist today, except the gliding arboreal animals are also 
capable of powered flight, and are in fact birds.
 
Also worth noting is anything capable of powered flight, is capable of gliding 
flight.
Even rotorcraft like helicopters can glide (and indeed there are foot launched 
autogyro gliders - i can supply video)

So I find the concept of a powered flight ability before a gliding ability as 
some proposed completely false (although some of their examples of gliding were 
albatross and vultures - such specialized gliding forms aren't needed to glide, 
and soaring should be differentiated from gliding).
Its either powered flight in tandem with gliding, or gliding, then powered 
flight later.
 
I think its highly likely powered flight did not come before soaring.
 

--- On Fri, 9/26/08, don ohmes <d_ohmes@yahoo.com> wrote:

> In my opinion, two scenarios are: 1) in a 'pre-powered flight'
> environment, dominated by gliders, repeated power dives (and subsequent
> pullouts) could convey advantage to predator and prey alike, assuming
> both are gliders. 2) where glide length might convey tactical advantage
> to a predator, such as a bipedal perch-hunter in an open or semi-open
> environment, gliding down on a terrestrial prey could culminate in a
> running/flapping style of pursuit (again, in a pre-power world). 
>
> This last would be the lifestyle of Arch. immediate ancestors, in my
> personal cartoon...