I think this is part of why snakes get such a bad rap- we assume other animals visually identify everything the way we do, but I've seen it many times where a snake is a very short distance from us- maybe after we just set them down, but suddenly they don't recognize us & they lash out- mistaking us either for prey or a predator. It's the way their reptile brains work- I've always found that for me the best way not to get bit is by keeping a snake close to me. Once there is space between you, there's room for them to misinterpret & make mistakes. Scent & touch are to a snake what language is to us.