By Paul Robbins, Nelson Institute for Environmental Studies
Anthropocene is a term introduced by chemist Paul Josef Crutzen in 2002. He proposed to assign this name to our current geological epic, relative to previous periods, like the Pliocene, Miocene, or Pleistocene, because human activities have come to have such a significant impact on the Earth’s genealogy and atmosphere.
Shift in Rock Chemistry and Layers
Indeed, stratigraphers, and those geoscientists who examine rocks and soils that make up the Earth’s strata, have argued that future geologists digging through the strata of our time will notice a notable shift in the rock chemistry and layers.
There’s, however, a debate over when the Anthropocene started. Crutzen suggests that it started maybe 200 years ago when James Watt designed his steam engine in 1784. But others have argued that the Anthropocene goes way, way, way back, all the way to the dawn of agriculture.
Earth and Humanity
In either case, the term is a clever use of language which merges the Anthropo—the human—with the geologic passage of time.
And one of the most notable things about the Anthropocene is the way it inverts a question that has historically been THE most important question geographers have tried to answer. And that was: What influence does the Earth have on humanity?
And yet, faced with a rapidly changing world, geographers have to ask the reverse question: What impact does humanity have on the Earth? The latter question, in a sense, renders the former question irrelevant.
This article comes directly from content in the video series Understanding Cultural and Human Geography. Watch it now, on Wondrium.
Unidirectional Changes
Added to this complication is the fact that many changes are unidirectional. That is, some human behaviors modify the environment, but halting those behaviors doesn’t always automatically mean that the environment will go back, or return, to its previous condition.
Many ecological changes follow this pattern. In the grasslands of Eastern Cape province of South Africa, for example, periodic burning of the land by the local people has turned the land into a highly productive grazing area.
Now, if burning is halted, as sometimes happens at the insistence of local authorities, the land doesn’t always recover its original mix of species.
Low-value Tree Scrub
The land often regrows into a low-value tree scrub, rather than an indigenous grassland. This may have to do with the amount of time required to recover the original species, or it may have to do with the introduction of new species over many years of history, as well as to the complex relationships between species in this grassland.
But, for whatever reason, the transformation is sometimes a one-way trip. In the Anthropocene, many landscapes and systems behave this way, meaning, that sometimes there is simply no going back.
Precambrian Period
Nonetheless, it’s important to remember that human beings are not the only life forms who have changed the geochemistry of the Earth over its history. During the Precambrian period, some two billion years ago, prokaryotes, anaerobic microbiota, thrived around the planet and had a huge impact on the Earth.
Prokaryotes took advantage of the atmosphere, which at that time had very little oxygen and a whole lot of carbon dioxide. These simple life forms were diverse, but they basically lived anaerobically, meaning, they were good at using water, sunlight, and CO2 to thrive and produce energy.
Prokaryotes
The waste product of the prokaryotes’ activity was oxygen, and over time, the success of these species led to a fundamental transformation of the atmosphere from one that was rich in CO2 to one rich in oxygen.
These little critters essentially created a world in which they could no longer thrive, but one that would make way for aerobic organisms who thrive on oxygen, like plants and dinosaurs and people.
Interestingly, anaerobic microbes live on today, but they live in swamps, and they live in our stomach, where they’re actually critical to our biological functioning. As it ironically turns out, the world they made way for is one better suited to species other than themselves.
Fundamentally Changing the Earth
Thus, one can clearly see that the Anthropocene might be the first time humanity has changed the Earth in a fundamental way, but it’s certainly not the first time living beings have changed the geology and the atmosphere of the Earth.
The crucial point, however, remains that will we duplicate the fate of the prokaryotes. Will we go the way of the prokaryotes and create a world in which we ourselves can no longer live- is a million dollar question.
Common Questions about Anthropocene Epoch
Crutzen suggests that the Anthropocene started maybe 200 years ago when James Watt designed his steam engine in 1784. But others have argued that the Anthropocene goes way, way, way back, all the way to the dawn of agriculture.
Many changes in the environment are unidirectional. This means that, some human behaviors modify the environment, but halting those behaviors doesn’t always automatically mean that the environment will go back, or return, to its previous condition.
Human beings are not the only life forms that have changed the geochemistry of the Earth over its history. During the Precambrian period, some two billion years ago, prokaryotes, anaerobic microbiota, thrived around the planet and had a huge impact on the Earth.
