The Sixth Extinction Summary

1-Sentence-Summary: The Sixth Extinction summarizes how human activity has contributed to the mass extinction of species and points out ways to mitigate our biggest environmental problems.

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The Sixth Extinction Summary

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If someone asked you what is mankind’s most important legacy at this point in history – what would you answer? The invention of the World Wide Web? Our collective knowledge expressed in modern science?

According to Elizabeth Kolbert’s award-winning book, The Sixth Extinction: An Unnatural History, our most significant legacy may be causing a mass extinction on Earth. This isn’t something to be proud of. But it does show the extent to which human activity has been reshaping the world’s ecosystem for thousands of years.

All of the five previous mass extinctions came by external forces of nature. We are talking fall of an asteroid and rapid cataclysms that dramatically changed weather and atmospheric conditions. Today, the human-induced cataclysm is seen as equally destructive to the Earth biosphere as those natural events.

This certainly adds some perspective to how homo sapiens fits into the big picture of our planet’s history. But is there still something we could do to stop – or at least mitigate – the effects of what we’ve “accomplished” so far?

Here are 3 lessons I’ve learned about the sixth mass extinction of the species which is happening right in front of our eyes:

  1. There are several ways in which the human race is responsible for the sixth mass extinction.
  2. Homo sapiens has been encouraging the extinction of various species long before the industrial era.
  3. There are many ideas for what we can still do to save at least some species.

Want to learn more about the real cost of human activity on Planet Earth – but also about ways to mitigate the harm we’ve done? Let’s dive in!

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Lesson 1: Human activity contributes to the sixth mass extinction in several observable ways.

Where do I even start? Human activity, especially during the industrial era, has affected other species in so many ways, that it is challenging to wrap it all up in just a few paragraphs.

One way in which we are causing mass extinction is the profound reshaping of natural habitats. An example of this is deforestation. By cutting down vast areas of woodlands, we are fragmenting the living habitat of a multitude of animals.

Along with their habitats, populations of those animals become fragmented as well. This leads to weakening species’ capacity for breeding – hence, putting them at a greater risk of extinction.

Further, there is global warming that is largely caused by human activity. Through emitting enormous amounts of greenhouse gases into the atmosphere, we are raising the average global temperature. These rapid climate changes affect, in the first place, the survival of those species which haven’t developed much tolerance to aberrancies in their living conditions.

Finally, another way in which humans contribute to the mass extinction – and which may not be so obvious – is our transportation. Why? By traveling extensively across continents we are unintentionally mixing species between different habitats where they don’t belong. Over the years, this is causing the effect that Kolbert calls “second Pangea.”

This means that the migration barriers that are essential to maintaining biodiversity start to disappear. As a consequence, we are observing the unification of biosphere across the globe – which means fewer species can survive.

Lesson 2: As soon as homo sapiens emerged, it started causing many species to go extinct.

It is fairly easy to observe the human impact threatening Earth’s biodiversity today. But, as scientists are now finding out, our profound impact on the planet hasn’t started with the industrial revolution.

In fact, the very nature of homo sapiens primes us to be a threat to the ecological balance. That’s because it is in our human nature to be restless, creative, solve problems, cooperate and take risks. All these evolutionary traits led us to transcend the natural limitations that no other species before us had. Unfortunately, they also turned out to be destructive to the world around us.

For example, early humans were really fond of hunting. They engaged in it so aggressively, that it threatened the survival of some big animal species in the prehistoric era. As Kolbert says, due to the use of increasingly elaborate tools, early humans became dangerous to big mammals that otherwise didn’t have a natural predator – such as rhinoceros or mammoth.

Due to their competitive nature, homo sapiens also had a hand in erasing their relative the Neanderthal. According to archaeological excavations, as soon as homo sapiens traveled to the areas where the Neanderthal lived, the latter started to disappear.

Lesson 3: There are many ways in which we can mitigate the sixth mass extinction – and that’s what we should be doing.

Kolbert emphasizes that all those facts about how destructive the human race has been in the world shouldn’t put us in a fatalistic mood. As I said in the previous lesson, the qualities that contributed to the homo sapiens causing the sixth mass extinction are the same ones that enabled us to advance as a species.

Recognizing this, we should foster our innate creativity, restlessness and cooperation skills to help save those species that we still can save.

Kolbert gives plenty of examples showing that this is not only possible – but already happening. Many writers have cared about other species enough to express those problems in their books. For instance, look at Rachel Carson’s Silent Spring, which became the springboard for environmental grassroots movements around the world! Her book was then followed by the US Congress passing the Endangered Species Act in 1974 and other similar national and transnational legislation worldwide.

Nature conservation and environmental activism have accomplished a lot since then – and evidence of this is everywhere. Today, we know beyond any doubt that humans have contributed a great deal to the destruction of the environment. But we also know that it is entirely in our power to improve upon that situation.

The big question is: will we use our power wisely?

The Sixth Extinction Review

The Sixth Extinction is a different kind of an environmental book. It tries to shift the rhetoric from blaming humans for the current environmental issues to simply naming facts. Among these facts are the innate qualities of the homo sapiens, to which Kolbert attributes the way in which our advancement has harmed the planet. This causes the reader to feel no guilt, which is common with other environmental reads – but rather, to understand the processes described and feel empowered to act.

Who would I recommend The Sixth Extinction summary to?

The 20-year-old environmental activist who think humans are to “blame” for the climate crisis, the 35-year-old young parent worried about the future of their children in the era of environmental threats and to anyone interested in natural sciences.

Last Updated on August 20, 2022

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Marta Brzosko

In 2019, Marta wrote 30 summaries for us as a freelance contributor. She is a facilitator, writer, and community wizard. Originally from Poland, where she attained a Master's Degree in Asian Studies, she now lives in Edinburgh, where she runs her own event agency called Contour. In her spare time, Marta loves running, camping, meditation, and dancing. You can read her summaries or reach her on LinkedIn.