It is well known from the fossil record that there have been a large number of extinction events of various magnitudes. Some famous examples include the Cretaceous-Tertiary extinction that killed off the dinosaurs 65 million years ago and the Great Dying 250 million years ago where almost everything died. It has been postulated that mass extinctions occur every ~30 or ~60 million years. Most explanations for these events are exogenous – some external astrophysical or geological cataclysm like an asteroid slamming into the Yucatan 65 million years ago or large scale volcanic eruptions. However, as I watch the news every night, I’m beginning to wonder if life itself is unstable and prone to wild fluctuations. We are currently in the midst of a mass extinction and it is being caused by us. However, we are not separate from the ecosystem so in effect, the system is causing it’s own extinction.
I listen to a number of podcasts of science radio shows (e.g. CBC’s Quirks and Quarks, ABC’s The Science Show, BBC’s The Naked Scientists, …) on my long drive home from work each day. Each week I hear stories and interviews of scientists finding that climate change is worse than they predicted and we’re nearing a point of no return. (Acidification of the oceans is what scares me the most.) However, in all of these shows there is always an optimistic undertone that implores us do something about this, under the assumption that we have a choice in what we do. It is at this point that I can’t help but to smirk because we really don’t have a choice. We’re just a big dynamical (probably stochastic) system that is plunging along. We may have the capability to experience and witness what is happening (a mystery of which I actually have the privilege to think about for a living) but we don’t have control per se as I wrote about recently.