Human History and the Biosphere Lecture 45
In the 20th century it became apparent for the ¿rst time that humans were beginning to have a huge and perhaps disruptive impact on many aspects of the biosphere.
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n the previous lecture we tried to stand back and survey the major structural changes of the Modern era. However, we deliberately skipped one large group of changes: changes in our relationship with the biosphere. These have a direct bearing on the question of sustainability. To see these changes clearly we must widen the lens further to include all of human history. In the 20th century, it became apparent that humans were beginning to have a huge and disruptive impact on many aspects of the biosphere. The term “biosphere” was invented by Austrian geologist Eduard Suess (1831–1914) and popularized in the 1920s by Russian biologist V. I. Vernadsky (1863– 1945). It refers to the region of Earth, water, air, and living organisms at the Earth’s surface that sustains life on this planet. The major turning points in human history are all associated with humans’ increasing control, or new forms of control, over the resources of the biosphere. This is what we generally mean by “growth.” But setting human history in the context of the biosphere reminds us that this was really a grab for resources by a single species: our own. By the late 20th century, it was apparent that our increasing ecological power was affecting the biosphere as a whole. John McNeill argues (in Something New Under the Sun) that our changing relationship to the environment may have been the most important change in the 20th century. To understand these changes, we must review our relationship with the biosphere over the 250,000 years of human history. What impact did Paleolithic humans have on their environment? The ¿rst distinguishing feature of our species was a greatly enhanced ability to adapt through collective learning. Adaptation itself implies an increased capacity
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