Biting is just like any other thing a toddler does. To toddlers it's no different to any other weapon in their arsenal - hitting, headbutting, kicking, scratching. To parents it seems base and animal-like, because as adults we sometimes hit or kick but we seldom bite. We seem to draw the line there. So Julia's biting it quite normal, and just an exploration of her world and the others in it. It is also a fantastically fast way to get what she wants, smart little girl

. It will pass eventually, and until then all that the carers can do is keep a close eye on her and intervene before a bite takes place. Of course this can be really tricky. Xander has always chosen biting over anything else, but has only ever bitten his brother.
I don't think something like time-out would work, especially on someone so young where it would be pointless. My thoughts are that a close watch is what is best, and she will move on from biting soon.