Re: Ornithurine diversity

[Dann Pigdon <dannj@alphalink.com.au>]

Quoting Michael Habib <mhabib5@jhmi.edu>:

> In any case, those skeletomuscular features might be a better place to 
> look for evidence of vertical burst launch in Mesozoic birds (not that 
> tail morph analysis isn't important, too).  As for the advantages, I
> agree with John's assessment - it has substantial anti-predation 
> ramifications.

I once watched a small falcon trying to prey on a flock of pigeons. It 
literally hung in the air without 
beating it's wings at all by facing into the wind. Several of the pigeons 
however managed to climb 
above the falcon, and maintained their position above and behind it by 
furiously beating their wings. As 
soon as the falcon began to dive on a pigeon below, one of the pigeons above (I 
assume they were 
adult males) dived on the falcon, causing it to swerve and miss it's intended 
target. The falcon would 
turn around and present it's talons to the attacking pigeons, but the pigeons 
were much too agile for it.

The falcons's low-energy approach to hovering may have been more energy 
efficient, but the pigeons 
high-energy hovering tactics made them more manoueverable and quicker to 
accelerate.  In the end 
the falcon went away hungry (as too, I would imagine, would have the pigeons 
after all that high-
energy hovering).

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Dann Pigdon
GIS / Archaeologist              http://geo_cities.com/dannsdinosaurs
Melbourne, Australia             http://heretichides.soffiles.com
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