These are all pretty bad, but nature doesn't need an animal or a poison to f**k you up. Really all Mother Nature needs to do is team up with Old Father Time and you, my friend, are screwed. Say, for example, you have decided to get out in the great outdoors for a bit of fresh air and exercise. It's a beautiful day for a hike, the sun is shining in the sky and all is right with the world. After a while, however, you find yourself up a remote mountain trail in the sweltering heat and life doesn't seem so rosy anymore. When your body temperature hits 39°C (about 101°F), your sweat glands are working overtime, squirting out precious moisture, making it difficult to stay hydrated. By 40°C, your vision begins to blur. By 41°C, you begin to hallucinate and black out. You sit down for a rest but now you begin to suffer from serious heatstroke. Your cellular metabolism has accelerated to 150% the normal rate. At 42°C, you are violently and repeatedly sick; your sphincters release, causing anything that was in your guts to flood out. 43°C, you begin to have repeated seizures. At just 44°C (111°F), The mitochondria in your cells break down causing internal haemorrhaging, your blood clots and your organs are severely damaged. The gut wall may perforate, releasing bacteria into your bloodstream. See? No dangerous poisons required, just add heat.
