my bearded dragons behavior

Question
i have a female bearded roughly 3 years old.after around 1 year of age(ive had it since it was a baby)it started to get agressive when i would try to handle it. ive heard it is unusual but not unheard of for this to happen and i was wondering if you had any idea why she would do this.

Answer
tom,
I've never seen an aggressive beardie, but I have heard of a few. My guess is that its just her personality; just like some dogs are mean and some arent. Its most likely random, and I doubt that anything you did had anything to do with it.

    However, she could be stressed; stress can be caused by a number of things, and it can result in aggressive behavior.
Does she have a climbing branch/rocks? Is her cage big enough? Is she being fed enough?..etc...all these things should be considered.