Long Recovery

Life forms on planet Earth have experienced some half dozen mass extinctions in the last 500 million years or so, during which up to 95% of species disappeared. Prior to each extinction event, the mixture of species had slowly settled into a stable balance, wherein each life form had found a niche that saw it interacting in cooperative ways with surrounding species—in ways that tended to perpetuate the blend. Evolution had slowed to a crawl, because the environment had stabilized and life forms had little reason to change.

Then some huge environmental upheaval occurred. An asteroid or comet crashed down, many large volcanoes erupted, noxious gases were burped up from the bowels of the seas, or the climate dramatically warmed or chilled. Many of those species that had been enjoying a long-term stable equilibrium suddenly found themselves with life’s comfortable rug yanked abruptly from under them. They had become a little too relaxed and vulnerable in their comfortable world. They couldn’t cope with the new harsh conditions and soon became extinct. Other species—some of whom had previously been scrambling for survival on the edges—found themselves better able to cope with the new environment. They adapted, survived, and thrived.

In the eons following each mass extinction, life on Earth slowly settled into a new mix of species. In fact, novel varieties of life came into existence in this aftermath, as evolution entered the fast track. Over time, life once again entered a stable period… until the next environmental catastrophe.

And the next mass extinction is currently underway. What is unique about this one is that it is not being triggered by a comet, asteroid, or volcano, but by one of Earth’s own life forms: Homo sapiens. This new dying off—designated the Holocene extinction—is being driven by human overabundance and overconsumption. We are now the force altering the biosphere.

Earth is still in the early throes of the Holocene extinction. Where it will lead and how many species will disappear is anybody’s guess. Society seems to be unable yet even to wake up and admit it is happening, so we continue to aggravate the process.

What humans understand even less is the rate at which these changes are occurring. To Mother Earth, this is the fastest mass extinction ever to transpire. While previous extinctions took thousands of years to pass, this one is speeding by increasingly faster—spanning just a few hundred years. To Homo sapiens that’s a fair passage of time. To the 3-4 billion year period of life on Earth, however, it’s an instant.

What we understand even less yet is that the recovery from the Holocene extinction will seem endless to us. In the aftermath of previous extinctions, life required millions—even tens of millions—of years recover. In contrast, we humans have been around just a few hundred thousand years. No one can begin to imagine what continued evolution will bring to Homo sapiens in a million years’ time. Once the recovery is over, it’ll be a very different planet. I wonder what the dominant species will be like then. Hopefully, one that’s smarter than humans today.