Human History and the Biosphere..................................................

LECTURE

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.

I

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