Snake Hearing - The Three Bones That Give You Hearing

We've always said snakes have poor eyesight and they're deaf to airborne sounds. But as we learn more, we determine that's not true. Binocular vision tree snakes are able to sneak up on camouflage lizards I can't see. And again, hearing will have evolved to suit the lifestyle of a particular snake. Some may have decent hearing, but it's not hearing as we know it,. There's also another sense we should touch on, which is the ability to sense infrared heat. So what are some of the biggest threats to snakes?