Re: Great in the air, not so good underwater

[don ohmes <d_ohmes@yahoo.com>]

One of the objections I have heard to the 'ground-up' scenario of flight 
origin; it seems to require that flapping capability/behavior precede the 
ability to generate lift. I say "seems" because it is possible to construct 
other scenarios.

Even so, if the hatchetfish is flapping but truly getting _no_ benefit, that 
may be more interesting from a flight origin perspective than the popular image 
of a flying fish w/ limited flight ability. If extended flight time/distance is 
of advantage to hatchetfish, I think jrc may be right in that it won't be long.

The key here may be what is really "significant" relative to lift generation. 
As any casino owner knows, even very small differences in probability add up 
over time.

Don

----- Original Message ----
From: jrc <jrccea@bellsouth.net>
To: habib@jhmi.edu
Cc: dinosaur@usc.edu
Sent: Friday, December 8, 2006 12:44:28 PM
Subject: Re: Great in the air, not so good underwater

As I said, they're not good at it -- but flapping while flying (or ballistic 
leaping with relatively large 'wings') is clearly compatible with an 
evolutionary path towards improved flight performance.  The eventually 
problem with that path is of course that they are not presently equipped to 
remain aerobicly powered during extended flight.  Wanna bet that they won't 
solve it in a few million years (if they survive) ?
JimC

----- Original Message ----- 
From: "MICHAEL HABIB" <habib@jhmi.edu>
To: <dinosaur@usc.edu>
Sent: Friday, December 08, 2006 10:40 AM
Subject: Re: Great in the air, not so good underwater


> I don't have the full paper (obviously), but David Alexander references 
> and summarizes it in his "Nature's Flyers" book.  Alexander remarks that:
>
> "Unfortunately for lovers of odd natural history, hatchetfish are not 
> capable of powered flight in air.  F. C. Weist showed that hatchetfish do 
> make spectacular leaps out of water.  They do not, however, achieve a 
> significant increase in distance by flapping.  Wiest found that they 
> follow ballistic paths when they leap."
>
> Cheers,
>
> --Mike
>