This chapter for me was focused on organisms that can survive in extreme conditions. How every square inch of the earth is inhabited by creatures of one kind or another. I learned the fundamental principle of biological geography, which is that wherever there is liquid water (h2o), organic molecules and a source of energy, there is life. I discovered the McMurdo Dry Valleys of Antarctica, whose terrains are the coldest, driest, and most nutritionally deficient in the world. Like some specialized species of bacteria and archaea they live in the walls of volcanic hydrothermal vents on the ocean floor, where they can multiply in water near or above the boiling point. It also describes an organism called hyperthermophiles, which loves extreme heat, and Deinococcus radiodurans, a microorganism that can withstand levels of radiation capable of killing humans and other organisms. The McMurdo Dry Valleys of Antarctica seem from his description barren and desolate. When I read the quote from Robert F. Scott in 1903, the first to explore the region, “We saw no living thing, not even a moss or lichen; all we found, inland among the moraine mounds, was the skeleton of a Weddell seal, and how it got there is beyond conjecture. The Weddell seal skeleton made me think that maybe it was once an ocean and has dried up over the years. But then it's Antarctica again, maybe he got trapped in a glacier when it melted and retreated, leaving the skeleton behind. It was shocking to discover that there are only twenty species of photosynthetic bacteria, long story short, mostly single-celled algae and strange and unpleasant-sounding microscopic invertebrate animals that feed on these primary producers. These organisms in this region are what science...... middle of paper ......and Future of Life by Edward O. WilsonAlfred A. Knopf New York. 2002.Brown, L. et al. (1999). State of the World 1998. New York: Norton.Chivian, E. et al. (1993). Critical condition: human health and environment. Cambridge, MA: MIT Press. International Council for Local Environmental Initiatives. Nations Footprint Report. Available at http://www.iclei.org/iclei/ecofoot.htm.McMichael, A. (1993). Planetary overload. New York: Cambridge University Press. Soskolne, C. L., & Bertollini, R. (1999). Global ecological integrity and "sustainable development": pillars of public health. World Health Organization, European Center for Environment and Health, Rome Division. Wackernagel, M., & William, R. (1996). Our ecological footprint. Gabriola Island, BC: New Society Publishers. World Health Organization (1998). World Health Report. Geneva: Author.