ANTA01H3 Chapter Notes - Chapter 17: Richard Branson, Bald Eagle, Lyme Disease
Document Summary
Human impact on the planet and on other life-forms: by most standards, homo sapiens is a successful species. There are currently 7. 3 billion humans living on this planet. Even so, we and all other multicellular organisms contribute only a small fraction of all the cells on earth most of which are bacteria. So if we see life ultimately as a competition among reproducing organisms, bacteria are the winners, hands down: humans have had an inordinate impact on the earth and its myriad forms of life. In the past, our ancestors had to respond primarily to challenges posed by nature. Today the greatest challenges for our species (and all others) are the vastly altered environments of our own making. Through our actions, which have caused widespread devastation of ecosystems all over the world, from the deep seas to the upper atmosphere, we have disconnected our species from its long evolutionary legacy.