How in the world do lichens (say: "like'-ens") survive on the hot, dry surfaces of rocks? Do they get most of their water from the air? Lichens are symbiotic "extremophiles." Consisting of two organisms helping each other, they thrive in extreme environments. We will do experiments that will hopefully tell us how they get water.   What you will need: Some lichen scraped from a rock     but not from a tree A sensitive weighing scale A humidity chamber (large bottle) Your experiments will have important implications leading to knowing how... humans can learn to live on Mars we can preserve body tissues for surgical organ transplants Be sure to see: www.science-projects.com/LichenWater.htm