OH MY! I thought you had her longer! You just got her a few days ago, so give her a while to settle in. I usually expect a minimum of 2 weeks for proper feeding and a few months for proper behavior.
Actually the iguana is VERY young. She may be a more dominant animal in the bunch which is why she is larger, she may be a few weeks to a month or two older, but she is still a baby. They are extremely flighty as babies, as are most baby reptiles. They are still basically wild animals and as such, they have natural instincts to how to behave when a predator is around, She is basically nervous and defensive. She is seeing you as the big hand in the sky coming to eat her. And yep WAY to young to sex properly!
Pick up Melissa Kaplans "Iguanas for Dummies"or James Hatfield's "Green Iguana; The Ultimate Owners Manual" Both will give you great tips on taming and socializing them!
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Cindy
PHFaust
