 there is a danger that it could get light-headed, like when you stand up quickly out of a chair, and all the blood rushes from your head. So if an aquatic snake tried to climb a tree, it would probably pass out. Oh really? Because it's not designed to be able to pump the blood up to its brain like that? It's all to do with where in the body the heart is. In most terrestrial snakes, and this corn snake is a terrestrial semi-arboreal snake, the heart might be a third of the way down the body.