Is this all snakes or just boas & pythons? My previous sources have said they (snakes) can see some color, but maybe the overall knowledge has changed & is now updated? My own experience with many snakes does suggest they don't visually make out "shapes" -to recognize us, for example. But I've also observed that some snakes appear to have much better eyesight than others. Either way, I make regular use of scent & touch cues to communicate with all my snakes. 'Cause I don't like bites, & I don't like snakes living in fear of the unknown.