Re: feather tracts (and spiny tails?)

[Jura <archosaur@reptilis.net>]

Facultatively bipedal lizards with autotomized tails don't stop running 
bipedally. They just compensate for their lost tails by running holding their 
bodies more erect. Could a dinosaur that attempted this tail loss strategy not 
do the same thing?

Also, as HP Ken Kinman mentioned, we are not talking about a heavy tail loss, 
just the tip or first 3rd. When one is running from a predator, it is the tail 
that is the easiest thing to grab a hold of. Even if it couldn't autotomize, it 
wouldn't lower its chances of being the first to get snapped.


_______________________

--- "Ken Kinman" <kinman@hotmail.com>
> wrote:
>
>Jaime,
>     As I said before, better to be a theropod with a balancing problem than
>a dead theropod.  The small forms which developed early protofeathers
>wouldn't necessarily have been obligate bipeds in the first place, and even
>if they were, the animal could often compensate enough to get by if the
>section of tail lost wasn't too massive.  Since the vast majority of the
>mass is in the proximal part of the tail, the loss of 20 or 30% of the
>distal tail length would not be a huge loss in mass (5-10% or less, maybe a
>lot less if the animal tail was long and skinny distally, but still "meaty"
>proximally).
>     And such a predator evasion strategy does not have to work all the time
>(far from it) to be successful for a species as a whole.   And finally, why
>would they have to necessarily be herbivores, as opposed to insectivores or
>even meat-eaters.  There is no rule that a bigger meat-eater can't pursue
>smaller meat-eaters.
>                 ------Ken

+++++++++++++++++++++++++

Indeed; I do believe we have all heard of tertiary predators :)

Jura



==
The Reptipage at: http://reptilis.net

Because reptiles are just cooler.

_____________________________________________________________
Visit http://freeservers.com to get a FREE Web site with a personalized domain 
and FREE Web-based e-mail.