it's too hard to say as it is so variable, depending on things like how much/often you feed them, what temperature you keep them at, what species they are, and their gender. really any figure i give you, you can probably find someone to say "i had a female that lived for twice that long!" for example, while somebody else may have had one that lived for half that! in general males live alot less than females as adults. alot of females can live for around 5 or 6 months, males 3 or 4 but like i said you may get some that live alot more or alot less, it just depends on so many things.