There are natural poisons that lurk in bacteria, plants, and fungi pretty much everywhere, and they're there for good reasons (according to the organisms that produce them) - but what is it about their chemical make up that makes them so poisonous? How do their toxins attack the human body with such deadly efficiency? Discover the answers to these and other questions as Hank talks about some of the most deadly natural substances in the world. Like SciShow? Want to help support us, and also get things to put on your walls, cover your torso and hold your liquids? Tardigrade Poster: http://vid.io/xom SciShow Mug: http://vid.io/xoa SciShow Shirt: http://vid.io/xog -- SciShow elsewhere on the internet: http://www.facebook.com/scishow http://www.twitter.com/scishow http://scishow.tumblr.com References and image licenses for this episode can be found in the Google document here: http://dft.ba/-5jCx