Any event that has occurred just five times since the first animal with a backbone appeared, some five hundred million years ago, must qualify as exceedingly rare. The notion that a sixth such event would be taking place right now, more or less in front of our eyes, struck me as, to use the technical term, mind-boggling. [Page 7]
The extinction of a species is an extraordinary event—think about a child learning that the dodo was essentially wiped off the face of the Earth by human behavior—yet there is a cycle where mass numbers of extinction events occur. For all intents and purposes, the evidence points us to a conclusion that human beings are about to witness a mass extinction of species.
Elizabeth Kolbert’s The Sixth Extinction: An Unnatural History is the most accessible book that I have ever read dealing with the science behind the extinction of species. Generally, books on this topic are dense academic or scientific works that quickly bore and confuse the general public with detail that is not of interest to the general public. Making scientific knowledge accessible to even an educated general public is no small feat and should be considered a success in and of itself. Furthermore, Kolbert weaves a rapid paced tale that engrosses the reader with both the amazing variety of natural life on the planet and the very precarious nature of so much of that life.
The story is quite simple. Humans are the weediest species on the face of the planet. As a species we inhabit all forms of habitats and manipulate those habitats to suit our preferences. Furthermore, through industrial development and behavior we have begun to fundamentally alter the chemistry of the entire biosphere. The end result is that as the conditions around the planet change a great number of species will be unable to adapt or move leading to their extinction. All that will remain will be the weeds of the plant and animal worlds.
How many species will go extinct? We do not know because “Yet another possible explanation for why observations don’t match predictions is that humans aren’t very observant.” [Page 187] We do not even know how many species exist at this moment in time, so if something is lost that was never discovered how will we account for its loss? The answer is that we will not and the world will be a less amazing place.
What frightens me the most in reading this book and others on climate change’s impacts is that we have no idea how forthcoming changes will impact the livability of the planet. It’s one thing to talk about aggregate temperature increase or species going extinct or sea levels rising, but it is another thing entirely to imagine the collapse of entire ecosystems because the connections between species are lost. The web of life seemed like such an easy concept to grasp when you are a middle school student in your first real biology class. It seems like a scary ass concept now that you are an adult staring at human derived climate change that is messing up the basic operating rules for the entire Earth.
I do not know if it is all doom and gloom. I would like to think that for the sake of my small children the world will not be such a grim place by the time they reach adulthood with children of their own. I just seem to lose hope the more that I learn.