Book Review - The Sixth Extinction by Elizabeth Kolbert

by Bill Boteler

In her new book, The Sixth Extinction. Elizabeth Kolbert  sets out to explain why the planet seems to be in a spasm of mass extinctions of plants and animals and to introduce the relevant scientific concepts, illustrated by her globetrotting visits to locations where this is taking place.

For those new to the concept of mass extinctions, the book’s title refers to the big 5 prehistoric mass extinction events as well as the current feared mass extinction. What these events all have in common includes a reversal of the ordinary rules of gradual change and adaption and a loss of a large percentage of species in a relatively short time. During such periods, the traits which allowed species to thrive are rendered useless by sudden environmental change.

Kolbert is an engaging science writer for the New Yorker and the short chapters are quick reading and should help introduce scientific concepts easily. She starts out with early naturalists trying to make sense of the fossilized remains of extinct animals within the context of the discovery of evolution. The uninitiated will discover how the idea of geological strata - a layer cake of rock going back in time - was discovered along with the existence of previous “creations”.

Initial theories of evolution favored the gradual change of living things adapting to their environment favoring survival of the fittest. The idea of catastrophic mass dyings was resisted until evidence gradually began to mount and it is only in our lifetimes, for example, that the the total annihilation of Dinosaur’s by a meteor strike was finally accepted with great resistance by the scientific community.

What has emerged from these studies is a picture of extreme geological events making life on earth suddenly difficult for a large number of life forms - sometimes in a very short timespan. A lot of this is geological sleuthing. Whole groups of creatures suddenly vanish from the geological strata. What happened? Sometimes it was continents crashing together and altering global weather patterns, other times it may have been massive volcanic eruptions spewing gasses into the atmosphere and killing off life in the oceans.

Once she introduces us to the idea of cataclysmic environmental change, Kolbert shows how it relates to our own epoch which some geologists want to rename the Anthropocene (age of man). Humans are burning fossil fuel stored away in rocks over 100s of billions of years and, in the process, changing the composition to the atmosphere back to what it was before prehistoric forests sucked the carbon out of the air. As we do this our climate returns to prehistoric conditions. Few currently living things are adapted to such a climate.

But as the book makes clear, there is more at work than climate change. Humans have unleashed a whole host of drastic changes that by themselves and, in interaction with each other, make it difficult for current plants and animals to adapt quickly enough to avoid going extinct.

Some of these include: acidification of the oceans as CO2 mixes with seawater, conversation of large areas of the land surface to human uses, destruction of forests, and moving plants, animals and their diseases across oceans where they can wipe out the native species that encounter them.

Kolbert goes everywhere. She hunts frogs with a flashlight in the jungle of Panama, dives on the Great Barrier Reef, observes experimental forest fragments in the Amazon, walks on dead bat carcases in an abandoned mine in upstate New York and watches a Rhino being inseminated at the Cincinnati Zoo. All the while she meets local scientists and conservationists at work. This makes for lively reading for people who may find a discussion of science to be off putting.

But she lays out the relevant concepts clearly enough. We are an ingenious species that has managed to invade all corners of the planet in a period of 10s of 1000s of years. On the way we gradually killed off most of the large animals that had not evolved to be wary of us. We created agriculture and modified a large part of the vegetation covering the earth’s surface. We created the industrial revolution and began to alter the composition of the atmosphere and the acidity of the oceans. We moved organisms across oceans where they reduced the native species. In fact, we even killed off or out-competed our near relatives, the Neanderthals, but not before mating with them.

She suggests we are a restless, “Faustian” species out to change everything in our path without always realizing we are doing it. At the end of the book she tries to add an upbeat note that we are also very caring about other species and what we are doing and that we can still do things which may help the situation. I expect future books may have more upbeat stories about how people are trying to address the problem.

As for the human impact of these events, I was impressed by a couple of things. She discussed one experiment where scientists off the coast of Italy are studying sea life near ocean vents where natural CO2 is bubbling into the water. Where the level of acidity reaches what it may be in the world’s oceans by 2100 AD, at that location she describes: “...the underwater equivalent of a vacant lot” (page 122). In other words, if we stay on our current path as far a climate change, we are looking at a wipeout of life in the ocean by the end of the century or at least that is how I interpret it. The ocean is responsible for producing not just fish but a large part of the oxygen we breath - about half. How will this much extinction affect our supply of oxygen?

I was also struck by a description of what happened to the inhabitants of “biosphere 2”, the experimental, closed ecosystem created decades ago in Arizona. Four bionauts entered that sealed environment for two years to live in a simulation of the planet’s ecosystems. It had farmlands, a rainforest, and its own mini ocean with a coral reef. Toward the end of their stay, the inhabitants didn’t have enough food or oxygen to breath. Is this just a coincidence? What happened to biosphere 2 is not identical to what is happening to biosphere 1, but we are also experimenting with what happens when you put 7-9 billion human beings and their pollution-spewing industries into an enclosed bottle.

Also, She observes that one of the reasons for the success of our species, unlike other primates, is our capacity to co-operate. That, along with our ability to create and use symbols such as language rather than our use of tools, which are used by other species, is probably at the root of the Sixth Extinction.

The Sixth Extinction - by Elizabeth Kolbert

Henry Holt and Company


Interested in further action?

●       Educate yourself by visiting some of the websites below or visit a library and check out books like Elizabeth Kolbert’s the Sixth Extinction.

●       Don’t buy products made from endangered species such as Ivory trinkets – even antique Ivory.

●       Don’t buy products from the destruction of natural habitats like rain forests. Coffee and palm oil products should be certified sustainable. Be very careful about buying seafood as much of it is imported from unsustainable sources.

●       Find out about conservation organizations and the many different species that they are working to protect. Join one or two and contribute to them.

●       Save energy, buy renewable energy, fight climate change because climate change will greatly accelerate extinctions.

●       Volunteer at a zoo, botanical garden or local environmental group.

●       Write letters to the media and to political officials letting them know you care about this issue and want more done about it.

●       Study and learn about nature and ecology because it is fascinating.

●       Encourage young people to experience and value the natural world by allowing them to go outside and by taking them to parks and nature reserves.

●       Create habitat in your yard for small animals like birds, butterflies and bees.

●       Finally, just don’t give up even if it seems that our current environmental problems are overwhelming. Small actions add up.