'Cosmos' Was Too Soft on Our Current Mass Extinction Event

Every week, Becky Ferreira, your hostess with the cosmostest, hones in on the most important science and history topics the hit show Cosmos glosses over. Previously: How the Pleiades Shaped Civilization.

Cosmos: A Spacetime Odyssey is marching into its final stretch, with only four more weeks to go. The quality has thankfully remained consistent from week to week, and last night's episode was no exception. “The Lost Worlds of Planet Earth” did a great job of demonstrating the dynamic identity of our planet, focusing especially on its history of catastrophic extinction events.

One of the show's recurring conceits is an ominous pyramid containing five “halls of extinction,” representing the mass die-offs the Earth has ever experienced. In yesterday's episode, Neil deGrasse Tyson emphasized the severity of the Permian-Triassic event, skimmed over the Cretaceous-Paleogene event, and implied that we may be on the cusp a sixth mass extinction, as yet unnamed.

Given how proactive the show has been about controversial content, it was surprising that the creators didn't go for the jugular on this point. The sixth extinction event does have a name: the Holocene extinction, an event that is currently kickstarting a new era called the Anthropocene. Though this name hasn't yet been officially adopted, a rising number of scientists agree it's time to wave goodbye to the Holocene period, and accept that we have entered the age of the human-shaped planet.

The term “Anthropocene” was first coined in the 1980s by freshwater ecologist Eugene F. Stoermer, and it quickly infiltrated the vernacular of many academics, most notably Nobel laureate Paul Crutzen. Though there is still vigorous debate over the fine details of the new epoch, the fact that it is happening is no longer seriously in doubt. Substantial interdisciplinary evidence suggests that the planet is being dramatically sculpted by our species, and that much of the damage is already irreversible.

The biological evidence is particularly sobering. Humans have undeniably accelerated the global rate of extinction, and we reduce biodiversity wherever we go (which, unfortunately, is everywhere). Even the usually chipper David Attenborough is pessimistic on this point. “It's not possible to reverse the damage we've done,” he said in a Reddit AMA earlier this year. “We are undoubtedly exterminating species at a speed which has never been known before.”

Indeed, humans are so invasive that we have managed to negatively influence habitats we haven't even explored. A recent study funded by the European Union found that trash has colonized the deepest reaches of the ocean. Researchers surveyed 32 locations in the Atlantic, Arctic Ocean, and Mediterranean Sea, and discovered human garbage in every single one.

Meanwhile, the Great Pacific Garbage Patch continues to grow, not to mention that every time an oil company messes up, dozens of local species end up endangered. Land environments have been almost entirely gobbled up by urban advancement, pushing several species into extinction and permanently altering their ecosystems.

According to environmental scientist Will Steffen, species are going extinct at a rate of 100 to even 1000 times the usual percentage, and the problem is only getting worse. “When humans look back, the Anthropocene will probably represent one of the six biggest extinctions in our planet's history,” Steffen told the BBC.

This is all without getting into the real smoking gun of the new Anthropocene order: climate change. Humanity has been edging out species for thousands of years, but it appears we were only warming up for the final act. The cascade of changes brought by rising global temperatures includes the acidification of the oceans, advancing sea levels, habitat loss, extreme weather, resource depletion, and, there is every reason to think, other effects that have yet to rear their heads. The Earth will keep a record of our meddling, and it may well be a geological obituary.

There's a reason there is so much confusion and denial when it comes to confronting the Anthropocene. The facts are overwhelming and depressing, as if an apocalyptic movie is unfolding before our eyes. Even Cosmos, which has valiantly exposed other unsettling truths, wouldn't touch the word “Anthropocene” with a ten-foot pole.

That's a shame, because the new era is here, whether we like it or not. Cosmos missed an opportunity not only to make this point, but to suggest that the human-sculpted planet doesn't necessarily have to be a cesspit of extinction, disaster, and suffering. There's still a chance that we'll learn how to establish a sustainable civilization on Earth, and even cede some of our territory back to other species. Sure, it's a rapidly shrinking chance. But given the alternative, it's worth our undivided attention.