I am at a climate change adaptation conference in Denver for three days, and I fully expected to come away from the experience thoroughly demoralized and depressed. At the end of day two, I find that I have both reason for hope and reason for concern. As a person who is well-versed in the scientific method, I have approached the climate change issue as a skeptic should: with a critical eye, and with a desire to hear multiple sides and multiple interpretations. It did not take much research of my own, though, for me to be convinced that climate change is occurring, and that it is extremely likely that it is being made much, much worse by human activity. Ultimately, this may well be what causes the extinction of the human species.
Scientists have determined that 99% of all species that have ever existed have gone extinct. That’s a huge number, but you have to consider that extinction is defined more broadly than the sudden disappearance of a species. Some extinctions occur through speciation; that is, an organism or group of organisms undergoes adaptation and evolution, and over time, changes enough that it is no longer the same species. For example, the common ancestor of chimps and humans, which lived about 5-7 million years ago, does not exist now; but (some) of its descendants do, in the form of Homo sapiens (humans); Pan paniscus (chimpanzees), and Pan troglodytes (bonobos). Other members of those two genera have also existed and subsequently gone extinct (e.g. H. erectus). So, extinction is not always the end of the line for an organism or group of organisms. Even the dinosaurs, many of which went extinct in the commonly perceived way (that is, they were wiped out entirely in a fairly short period of time, geologically speaking) have living descendants. We call them birds.
If things continue the way they have been, I’m not sure humans are going to have any descendants. And I also think that humans will be the first species in history who have caused their own extinction. Most species go extinct in one of two ways I described above: through adaptation and speciation; or through an inability to adapt to new or changed environmental circumstances. The dinosaurs, and many other organisms who lived 65 million years ago, were unable to adapt quickly enough to the changed environment following a catastrophic asteroid impact, and so they died. The asteroid impact was a random event over which the organisms had no control. Humans, on the other hand, are paradoxically bringing themselves (and not incidentally, many other organisms) to the brink of extinction because they are so good at adapting to their environment. This is a case of too much of a good thing, and when it happens, what used to become adaptive becomes maladaptive and starts to negatively affect the species.
How is the human ability to adapt to the environment bringing about our own potential demise? Humans are supremely skilled at technological innovation. What started with stone tools has evolved to microprocessors, digital technology, nanotechnology, genetic modification, and so on. These things are built on a basis of energy and raw materials extraction. Our technological abilities led to the ability to grow more food, have more children, live longer, and make more and more things. In biological and evolutionary terms, an organism’s ability to reproduce is measured as a level of fitness; and the more offspring you produce, the more fit you are. For many organisms, and for animals in particular, mate selection depends on fitness characteristics – males battle each other for the right to females; females select mates based on displays of desirable traits. For humans, one of the most salient traits is status. The higher an individual’s status, the more likely that individual is to mate and produce offspring – that is, the higher his or her fitness. Status is also linked to the ability to raise offspring to maturity. In humans, status is often linked to power, power is linked to wealth, and wealth is indicated by material possessions (among other things). So, the more stuff you have, the more status you have, and the more power you have, the more people – including potential mates – you control. I don’t want to be too broadly sociobiological about this, but for all intents and purposes, our incredible ability to innovate and adapt through making tools is a direct result of the biological imperative to mate and maximize our evolutionary fitness.
So, what does our drive for evolutionary fitness have to do with climate change? It’s simple, really; making tools is what we do. Gathering material things to show our status is what we do. Using yet more tools to make having more material things easier is what we do. Desiring material things to show our status is what we do. Innovating, adapting, making the path of least resistance easier and easier and easier is what we do. Competing for resources is what we do. Dividing ourselves into status hierarchies is what we do. Trying to climb higher and higher up the status pyramid is what we do. And to do these things, we have created more and more tools and technologies that are requiring more and more energy and more and more raw materials, and the technologies we use are having a hugely disproportionate impact on the global environment. Put every one of the over 7 billion people on the planet together in one place, and they don’t take up much space, in terms of square mileage; we can all fit pretty neatly standing side by side in an area about the size of Los Angeles County. But our impact – the impact of our technologies, of everything we harvest and cut and mine and burn and use – is global in scale. We have pushed the bar so high that going back seems impossible.
I know there is much, much more to it than what I have written here, but I really, truly believe that at its very core, it is the biological imperative gone to extremes that has led to the unintended consequences of humans adapting themselves into maladaptiveness. I can also have hope that our innovative, tool-making genius may save us yet. This is not the last I will have to say on this subject, but you have to start with first principles, and I believe our evolutionary history holds that position.