 In a truly arboreal snake, the heart is going to be maybe a quarter of the way down the body. So closer to the head, so that it doesn't pass out when climbing a tree. That's a very clever adaptation. And there's adaptations to the lungs and all sorts of things, and to the actual tissues as well, to stop blood pooling. I'm just amazed with how perfectly chilled the snake is. This is really helping my fear of snakes.