Fear of snakes?

Is a fear of snakes learned? Or is it part of Eve's punishment from Eden that it's just an innate fear? Where does it come from?

William woke up at 1am screaming bloody murder 'mommy mommy help me!' over and over. We ran in his room and he started screaming about snakes hurting him and was pointing all over his bed. We tried to calm him down and cuddle
With him and let him know that the snakes are all gone and he's ok, but he was nearly inconsolable. We offered to take him to our room for a change of scenery and he liked the idea but the first 3 times he was almost asleep he jolted up, again screaming about snakes. We finally got him back to sleep and took him back in his room, but we were both just surprised by it all.

Anytime he's been to a zoo with snake exhibits he has loved to look at them. Last Halloween he let big giant amazon type snakes slither in his lap and loved it. So where does the fear come from? We've never told him snakes bite, he's never seen a snake bite, so how did his brain dream of it?

His little mind amazes me, but this time I wish he just hadn't crossed over into the realization that snakes can hurt him. Poor bear :( I don't like for him to be so scared!!!

Any ideas on where it comes from? Or how to help it?!?


- manda