[hsitz]

"The icon doesn't necessarily have to look like anything ... we just have to evolve in a way that gets us to jump out of the way."

Well, the icon does have to look like _something_, if we're going to see it. So seems good question of why it looks like a snake, rather than something else, whether there's something about the "real" snake that constrains how we must see it if we're to use icon to successfully adapt our behavior. E.g., an icon of a snake that was shaped like, e.g., a sphere or a box, would not be very helpful if we wanted to pick the snake up with a stick to move it out of the way.