Don’t Panic – How Humanity Might Survive the Next Million Years

Our species is going to go extinct. We may have descendants – a new species, or some sort of post-human meld that we construct ourselves – but the long roll of lost creatures preserved in the fossil record leaves no doubt that extinction is inevitable. But just as the survival of the human lineage is only a vague possibility at this point, our eventual downfall also remains in the realm of the unknown. Our destruction could transpire in a blink of geologic time, or be at some future point millions of years hence. What will make all the difference is our ability to learn from the past and how we use that knowledge to construct the foundation of our future. In Scatter, Adapt, and Remember, io9 editor in chief Annalee Newitz considers just that in an optimistic exploration of how the key to our long-term survival can be forged from prehistoric clues and technological possibilities.

So far, there have been five absolutely devastating mass extinctions in the history of life on Earth (with a smattering of lesser, but still calamitous, events scattered through time). And if we’re not actually in a sixth mass extinction right now, we’re not very far off from the tipping point. The blame for this state of affairs rests with us.

We’ve drastically altered the Earth’s climate and seas through greenhouse gas emissions, we are spreading invasive species around the world, and we’ve taken a horrifyingly active role in directly destroying a variety of species and ecosystems. And given all this change, we’re not guaranteed a persistent place on the planet. As adaptable as we are, we’re still the last human species in existence and can only claim a relatively short tenure on this planet – our species has only been around for about 200,000 years. Whether we’re snuffed out in the next few millenia or extend the track record far into the future relies on our abilities to understand the risks that face us and responsibly use the best scientific tools at our disposal to mitigate against our self-imposed threats.

Learning from prehistory is one way to outline possibilities of what the future might hold. Paleontologists with an ecological bent have already begun to investigate these potentials, looking to how organisms have reacted to climate change and other familiar phenomena in the past for a view to what makes the difference between persistence, evolution, and extinction. To that end, Annalee* briefly surveys four of the Big Five mass extinctions, reiterating the point that there have always been survivors. If there had not, we wouldn’t exist. Our ancestors, as well as the ancestors of every other species in existence today, persisted through extinction’s worst and continued to change through the ages. And while what makes the difference between death and survival during global disasters is still being debated for all of these extinctions, some trends – such as being a widespread generalist capable of wandering far to rare resources in extinction’s aftermath – give some organisms an advantage over specialists restricted close to home.

Threats to our existence don’t always come in the form of asteroid impacts or intense volcanic activity, as they were during some mass extinctions. Disease and famine have horrifically ended human lives much closer in time. From the fall of South American civilizations to the Great Irish Famine, Annalee also surveys dangers that we create for each other, from the spread of disease and war to the mismanagement of arable land. But after cataloging all the dangers, including the blip in prehistoric time when our species almost went extinct prior to a dramatic rebound, Annalee begins to lay out possibilities for survival in a conversational style that would feel just as at home on io9 as in a book.

Some of these examples in the middle section don’t entirely fire. While the long-range migration routes gray whales employ are certainly important for their survival (the “Remember” example of the title), Annalee recognizes that human conservation efforts and future attempts not to disturb the whales are why the cetaceans still exist in the Pacific today. Still, Annalee sets up the general strategies of being able to wander far, shift with changing conditions, and recall what survival tricks worked in the past as hopes that mold more specific ways in which we might allow humanity to avoid extinction for a long time yet to come.

Lessons of death and survival can be drawn from a variety of examples, from organisms that withstood mass extinctions to people who succumbed to pandemics in recent history. And the point of this reflection, Annalee writes, is to ask “How will we convert our guardedly hopeful stories of a human future into a real-life plan for survival that avoids some of the worst failure modes?”

An initial step involves altering cities, especially as our global population continues to climb. Aside from relatively abstract goals that depend on those living in a particular place – such as an openness to innovation and created areas of shared green space – Annalee also investigates the technologies that may allow us to survive in the near and long term. Carefully-designed subterranean cities might be essential in the aftermath of nuclear war or a terrible asteroid strike, while buildings partly made of biological materials might reduce energy costs while providing us with a space to grow food right where we live. Likewise, a better understanding of the way earthquakes and disease work, paired with models that better predict the damage such phenomena cause, could allow us to make ourselves more resistant to such persistent challenges and respond more effectively. Tragically, as Annalee recognizes, the benefits of such innovations will be spread unequally. Those in affluent, developed nations are more likely to see the kind of safe, green cities that Annalee describes, while people elsewhere will suffer.

The promise of geoengineering raises the same dilemma. Scientists and engineers are trying to come up with solutions to global climate change, ocean acidification, and other problems that are global in scale. Given the experimental nature of programs – such as creating more cloud cover to partly block the sun while also trying to lessen the amount of carbon dioxide in the atmosphere – no one really knows what such endeavors would do in this country or that as weather and climate patterns changed. We do not live on a homogenous planet, and alterations that benefit one part of the globe might devastate another. If we’re going to modify the planet to best suit our needs and survival, as Annalee argues we should if we want to celebrate the millionth birthday of our species, who will decide what changes to implement and how?

Many of the possible solutions Annalee discusses are still in the realm of science fiction, or, at least, speculative science beyond the reach of what we can presently achieve. That’s not to say that tweaking Earth to better ensure our survival or even setting up shop on a distant planet are out of the question. Technology, politics, and culture will constrain our long-term efforts at survival, but given how much the human experience has changed during the past century – not to mention our cultural evolution over the relatively scant 200,000 years since our species originated – how strange our future might be is a tantalizing  mystery. Will we live in a Star Trek like existence, strange yet still familiar? Or will “human” mean something entirely different – people genetically altered to cope with life elsewhere in the solar system, or perhaps digital copies of minds that have an almost immortal life inside machines? More likely, humanity one million years hence – if we ever get that far – will be something far stranger than we can imagine today.

We won’t ever live in the glow of another star unless we ensure our survival on Earth, though. The challenge that faces us, Annalee demonstrates, is how to pair new ideas and innovations with what already exists. We can’t simply start from scratch. The world of tomorrow is going to be built on top of and around the world we know. And even if we can predict the forces that might drive us extinct, there’s no guarantee that we’ll have the time or tools to react to such threats. But there’s hope that we can.

In the end, survival will mean stretching our perceptions of what is natural. The idea of “hacking the planet” or altering ourselves to better match our surroundings might sound anathema to some, but the truth is that we are already doing so. The history of Earth is one of dramatic and constant change, and trying to recapture some romantic notion of Nature would be ignoring the reality of persistent planetary permutation and the way we’ve already made use of the Earth (for good and ill). Even restoring damaged habitats requires human intervention and stewardship – places of we think of as wild still bear our distinctive fingerprints. Maintaining the dichotomy of “human-made, bad; natural, good” will help no one. Instead, we need to recognize and come to terms with our capacity for both destruction and preservation – to use the best of our scientific knowledge and imagination to predict what tomorrow might hold and make careful decisions of what the future of Earth is going to be like for our species and all the others that dwell here. Annalee’s new book is a hopeful overview of such a possibility. We’ll never have total control of the planet nor our ultimate fate, but we have the ability to explore what we want the future of our species to be like.

*Since I know Annalee personally and have worked with her for some io9 posts, I decided to call her by her first name in this review.

Further reading: Annalee wrote a guest post for this blog about her favorite icon of long-term survival, Lystrosaurus.