Humans are weird when it comes to thinking about the end of all things. Almost all of our mythologies have built-in warnings about eschatological scenarios in which all the bad is purged and the good starts again. This may reference actual cycles in the earth's history that our species understands unconsciously. Science has given us some evidence that, when compiled into a timeline of the earth’s total age, suggests that there have been several cataclysmic moments that have wiped the planet clean like a teacher erasing her whiteboard.
We ought to be aware of our frailty and how quickly and unexpectedly life can end. Even so, like reckless teenagers, we pretend that death won't happen to us to justify continuing behaviors that perpetuate disastrous consequences. We hear all the time about horrible car accidents caused by distracted driving, yet we continue to operate vehicles while looking at our phones. We keep smoking, knowing that it causes cancer and other pulmonary diseases; we ingest ungodly amounts of fat and carbohydrates knowing it causes obesity and diabetes and we pour gallons of soda, beer and liquor down our throats, aware that it can cause anything from liver disease to mental decline and death. None of these considerations are enough to keep us from putting ourselves and everyone else in danger. We obviously have the same response to planetary destruction.
This tendency in our species may come as a marker of our cosmic inheritance. The universe, too, is living dangerously; cyclopean creations and monstrous destructions are occurring at every moment. Our poor planet lives on a knife edge of stability in an infinite sea of malevolent antipathy and indifference to life. At any moment, this precariously balanced little orb could be snuffed out, either from within or from some outer threat that we have no way to anticipate or counteract. If you imagine a goldfish bowl propped on a rickety platform at the end of a particularly busy shooting range, you will catch my meaning.
To extend the illustration, it may be doubly arresting to note that the bowl is overcrowded, food is scarce, grudges and battles occur between individuals, pollution is rising, oxygen in the water is rapidly depleting and some are attempting to seize 'total power and control'. A handful of the goldfish believes that the Great Goldfish is coming to save them and that the survivors of the coming cataclysm will be the 'pure and chosen few'. This reflects the extent of self-awareness in our purblind species.
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Our planet is quite young in the cosmic scheme of things. Even so, it has already experienced six extinction-level events. The likelihood of a nightmare ending for Earth is far more statistically probable than any long-term utopian future. Just ask the goldfish. With that in mind, though, it may help to add context to this idea of mass extinction by understanding what came before meager homo sapiens arrived on the scene. Our planet is far older than the six thousand years popularly agreed upon by the people who build replicas of Noah’s Ark theme parks in Kentucky and believe that dinosaurs lived at the same time as humans and that a flood wiped out all life.
The first devastation of the earth, the Ordovician extinction, occurred about 440 million years ago. At this point in the earth's long history, most life dwelled in the oceans. Massive fluctuations in oxygen levels, sea-level decline and global cooling devastated about 85-90% of all living things during this initial cataclysm, though it occurred over a geologically long time frame possibly as a result of tectonic plate movement.
The Late Devonian Extinction happened about 370 million years ago (only 70 million years after the Ordovician). For 25 million years or so, the earth became uninhabitable to the life that had survived and thrived from the previous cataclysms. Temperature fluctuations and the widespread death of plant life that helped to regulate the oxygen content in the atmosphere are possibly to blame. One or perhaps several ice ages had also occurred in the lead-up to the Devonian, creating a truly hostile environment for all but the hardiest life forms.
Next was the Permian-Triassic extinction. This buffet of killer delights has been nicknamed The Great Dying. Life on the planet—upwards of 95%—was casually destroyed, scouring the planet mostly clean. Scientific speculation suggests what may have happened to cause this brutal destruction. About 250 million years ago, climate change, mass expulsion of greenhouse gasses from the seafloor from tectonic shifts, the resulting volcanic activity or perhaps a massive chunk of space debris caused a forbidding series of cascading devastations, all of which caused mass extinction on an unprecedented scale.
The Triassic-Jurassic extinction followed. This event happened so long ago (200 million years) that no one is quite sure what happened. It is possible that a combination of massive ecological and geological coincidences worked together to create an eons-long nightmare scenario that we cannot fathom.
As if these weren't enough, next comes the Cretaceous-Paleogene extinction. This is the most well-known cataclysm because it is the event that killed off most early forms of mammalian life and all the pterosaurs and non-flying dinosaurs. This extinction has often been represented humorously (though morbidly) as a pair of tyrannosaurs watching a falling star and asking each other about lunch plans for Thursday. This extinction happened only 60 million years ago but was likely precipitated by a series of atmospheric and chthonic events that were permanently punctuated by the impact of a big space rock smashing into the crust and causing a millennia-long nuclear winter.
If you're counting (and I hope you have been) you're wondering why there are only five mentioned, when I said that there have been 6 total mass extinctions. We are currently in the last one, called The Holocene Extinction. The term mass-extinction event promotes a mental image of things coming to an abrupt and explosive end. Actually, many of the events described took hundreds of thousands of years or more to reach the fullness of their destruction. Certainly, a comet or asteroid striking the surface can add speed to the circumstances, but generally, these events are agonizingly slow to a human understanding of time.
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Our current extinction has been going on nicely for about 10,000 years. Most of the creatures that have perished in that time have died off due to environmental changes that cause habitat loss. Significant destruction of rainforests, rising sea temperatures, loss of species, geological catastrophes and sudden shifts in oxygen content in the water and the atmosphere have all played a part. Most terrifyingly, though, one species has aided in the Holocene Extinction more than any other.
Since humans have been on the scene and started building civilization (around 3300 BCE), the people living in those civilizations have needed to eat and have access to other amenities. For about one thousand of the last 10,000 years, humans have been actively destroying habitats, overhunting and fishing, polluting ecosystems and trashing populations of everything from clams and mussels to whales and tuna. On land, our systematic deforestation has killed off species that we're not even sure about other than that they're gone. Each year anywhere from 10 to 100 species go extinct forever. That's a horrifying reality.
In the Carolinas, an indigenous parakeet's plumage (Conuropsis carolinensis) was so popular for women's hats that they were hunted to extinction in just under 80 years. Perhaps ironically, it is now believed that these bright green birds were already on the way out, possibly just from the expansive growth in human, equine and livestock populations and the introduction of cats (though, it is now thought that the parakeets were poisonous and that the cats may have gotten their comeuppance). That's just one example. Humans have helped to speed up the current extinction by upending existing balances in our search for oil, lithium, titanium, iron, cadmium, copper, tin, aluminum, arsenic, silver mercury, nickel, lead, coal and natural gas and our endless need for makeup, cotton, metal, gasoline, bullets, bread, meat, cheese, tobacco and grain alcohol, smartphones and computers, cars, airplanes, rockets and a means to transport them all over our planet.
Humans are a warlike species and our continuing need to acquire other people's land and justify genocide in the name of political affiliation can also be what sends us over the precipice into our own extinction. The final crunch for us may be the equivalent of all the goldfish swimming to one side of the bowl and tipping it over. That doesn't mean there aren't cosmic bullets out there headed this way at devastating speed, but by the time they hit, humanity, and all life may already be gone.
Eye-opening as this ought to be, though, humans still justify destroying our planet as if we hope to speed up the oncoming destruction. This somewhat suicidal pursuit of detrimental goals seems antithetical to long-term survival. It may be that, like the millions of other species that have come and gone, we are destined to be dug up in another 50 million years by some other sentient beings that evolved and rose to prominence long after our goldfish bowl tipped over into oblivion. This plummet has already begun and nothing, not even the end of carbon-based fuel addiction or everyone becoming vegan, or total human equality and unity can stop it. Those things cannot hurt—they will help to slow the eventual destruction—but it will take a planet-wide understanding of the mortality of our species to get us to stop trying to rock that goldfish bowl to the edge of the abyss of extinction.
Because I was nearly hit by a driver looking at her phone on the way to work, today, that doesn’t seem likely.
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