[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: FW: Concavenator corcovatus, a new humped carcharodontosaurid from Las Hoyas

Dale... Dann pretty much beat me to the punch.  Rather than parrot
him, I'll just say "I agree with Dann" ;-)


On Wed, Sep 15, 2010 at 8:14 PM, Dann Pigdon <dannj@alphalink.com.au> wrote:
> On Thu, Sep 16th, 2010 at 9:27 AM, dale mcinnes <wdm1949@hotmail.com> wrote:
>> If sexual behavior is at the root cause of the elongation of spine growth 
>> then,
>> why DON'T we see more of this in other clades?? This should be occurring 
>> everywhere
>> since sexual selection is also everywhere in every clade and NOT dependent 
>> on envir-
>> onmental regimens.
> There are numerous reasons why neural spine elongation wasn't always the 
> 'sexiness of choice':
> 1) Not all species may have used visual displays to attract mates. Some may 
> have used scent,
> song, or courtship 'dances'. Sometimes all you need to get the girls is to be 
> able to kick your
> opponents' arses in intraspecific combat - where in fact a lack of impeding 
> adornments might even
> be an advantage.
> 2) Of those that used visual displays, bright colouration may have been 
> preferable to changes in
> body form. Perhaps those species that resorted to costly changes in body form 
> simply lacked the
> genetic resources to evolve bright colours or bold markings.
> 3) Elongated neural spines may have been just one type of display structure. 
> Crests, frills, horns,
> spikes and plates may have also been primarily for display purposes in some 
> species.
> --
> _____________________________________________________________
> Dann Pigdon
> Spatial Data Analyst               Australian Dinosaurs
> Melbourne, Australia               http://home.alphalink.com.au/~dannj
> _____________________________________________________________