Petco doesn't have a policy about the genders of animals and generally the company frowns upon an employee trying to sex an animal, since there is a potential to hurt it if the employee isn't careful.
If you can find a good herp store around you, chances are they sell probe kits and they'd be able to show you what to do, or how to pop. LLL Reptile is 30 min away from me and they regularly pop animals for customers so they'll know the gender of what they're buying.
~jenny
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"The python has, and I fib no fibs,
318 pairs of ribs.
In stating this I place reliance
On a seance with one who died for science
This figure is sworn to and attested,
He counted them while being digested."
~Ogden Nash
jenny.thegreenes.org
"If you're happy and you know it,
Bomb Iraq!
If you cannot find Osama,
Bomb Iraq!
If the terrorists are frisky,
Pakistan is looking shifty,
North Korea is too risky,
Bomb Iraq!
