I believe that certain species of snakes are more intelligent than others, which means them can be more observant of their surrounding, smells, etc. Do I bleive they are affectionate, not really, I think its even hard to say they "enjoy" being held, I think they tollerate it, some better than others. Now if we open it up to other reptiles vs. just snakes it gets a little more interesting. If we look at lizards, again some are highly intelligent and others not so much.

Do I think they display affection I really don't know, but I can tell you my Blueys will come to the door when I open the cage, climb out on my arm and perch on my shoulder and just sit while I walk around. If I pull them down they will climb back up, they are very relaxed and will do this with anyone, so it's hard to say thats affection.

Now my tegu is another story. She still confuses me because I would love to know what goes on in her head. She is very intelligent and inquisative. I can open her cage door and she will look around to see if she is getting fed or not. If she realizes there is not food she will come to the opening and lay her head on the track, I pet it a few times and she will crawl out on my arm and free roam. There have been times where I put food on one end of the room and I stand on the other and she comes straight for me and ignores the food. Then there are other times where she comes out of the cage (no food in the room at all, and no scent on my hands), sits on my lap and lunges at my hand in a feeding strike, then backs off and stares at me. She always goes back in her cage on her own. There are other times when I open the door and wait for her to come out and she won't. She does recognize me vs my wife and acts differently with each of us. Again it is hard to say IMO that this is a display of affection, but there is a lot going on in her brain.