December 13, 2010
Human Extinction: Not the Worst Case Scenario
The year is 3010 and an interesting new species has evolved: a muscular, knuckle-walking primate with sparse body hair and a strikingly human face. It appears to be deformed, with extra non-functional limbs in various anatomical positions--like something out of a sci-fi horror story or a genetic engineering experiment gone wrong. The creatures are vicious. Individuals routinely attack and eat members of their own species.
This generally isn’t how we envision our species a thousand years from now. More typical scenarios feature technological advancements, like flying cars and intergalactic travel. We might imagine that future humans will have eliminated disease and extended our lifespans substantially.
It’s debatable as to which of these scenarios is more likely. And of course, both could be far off the mark. But this much is clear: there’s trouble ahead for our species if we continue on our current path. The problems that future generations will face are largely predictable.
Our environment is becoming increasingly toxic, with carcinogens and teratogens, allergens, hormone distrupters, and pharmaceuticals accumulating steadily. Such pollutants also build up in the tissues of animals that we eat and depend upon.
Food shortages are anticipated. With the population increasing at alarming rates, there’ll be a lot more human mouths to feed. Heavier reliance on meat will worsen environmental problems, making clean drinking water harder to find. Non-animal food sources may also be much scarcer. If honey bees succumb to the threats they currently face, we’ll lose most of the foods that depend on bees for pollination.
Disease will be rife. Infectious disease will likely rise with the loss of biodiversity. Authors of a paper published last year in BioScience suggested that biodiversity loss “can increase the incidence and distribution of infectious diseases affecting humans."1 Authors of a more recent paper appearing in Nature came to a similar conclusion, noting that, in many cases, biodiversity “seems to protect organisms, including humans, from transmission of infectious diseases.”2 Increased population size and proximity to one another will exacerbate the problem.
Cancer and environmental diseases will be widespread due in part to the greater toxicity of the physical environment and the foods we eat. Genetic disease is also expected to rise sharply. Michael Lynch, in a recent paper published in PNAS, suggested that the accumulation of deleterious mutuations will have a profound impact on members of industrialized societies within a few hundred years.3 He states: “Without a reduction in the germline transmission of deleterious mutations, the mean phenotypes of the residents of industrialized nations are likely to be rather different in just two or three centuries, with significant incapacitation at the morphological, physiological, and neurobiological levels.”
A society in which the majority of people have some degree of inherited or acquired disease won’t be able to function as our current society does. Presently, healthy able-bodied people in Western societies generally support those who are less fortunate. However, presently, healthy able-bodied people are the norm. What would happen if we all had some degree of impairment?
If we continue on our current path of unbridled consumerism and environmental destruction, the most likely future scenario is not one with flying cars and intergalactic exploration, but one with widespread disease and starvation, in which the quality of human lives is relatively low.
I think we can safely make two predictions: our species will have a markedly different array of traits in a few hundred years and we will be living in a vastly different environment. This has important implications for our evolution. With a different array of traits and a different fitness landscape, we can’t predict which traits will be most advantageous.
Of all of the species that have existed on the planet, only one has ever evolved the sort of intelligence and morality that distinguishes humans. It’s exceedingly rare that high intelligence arises through natural selection. It’s not safe to assume that either intelligence or morality will continue to be selected if our conditions change dramatically.
Circumstances are powerful determinants of human behavior. Plane crash survivors in the Andes ate less fortunate passengers in order to survive. Crime rates tend to surge when natural disasters strike and people will trample one another to escape a burning building. In a toxic environment where food is very scarce and dependent humans outnumber abler types, will morality confer fitness? Or might those who see members of their own species as an abundant, relatively uncontamined source of protein have an edge?
The average modern human may be more intelligent than the average human living a thousand years ago; but it is the gain in collective human intelligence that is most impressive and consequential. Our collective intelligence has given us technological and medical advances that greatly improve the quality of our lives. This intelligence is largely dependent on our technologies for storing and sharing information and on social infrastructure. Without industrialization, high quality education, and a healthy work force, we wouldn't enjoy these perks of modernity.
Civilization obscures our similarity to other animals. We tend to hold ourselves to different standards because we see ourselves as above nature. Many people find the slaughter of food animals objectionable. Yet no one is advocating intervention to save the gazelles from the lions or the rabbits from the foxes. Is the suffering of animals in the wild less important? Should we venture out in search of prey animals to rescue from their predators, and sick or injured animals in need of medical care? No, it would seem. It’s okay when nature imposes suffering on animals, but not when we do it. Similarly, it’s not okay when we are the subjects of nature's cruelty.
Civilization has bestowed our species with a distorted self-image. Many people seem to have the impression that we operate independently of nature. We are fortunate that we’ve been able to act as though we are independent for as long as we have. If we don’t adjust our way of living so that it becomes sustainable, however, nature will eventually do this for us.
The worst case scenario is not that humans will become extinct, but that we will come to experience the cruel will of nature as other animals do. We can’t rule out the possibility that we will become more similar to our primate cousins in intelligence, behavior, and quality of life. We may be enjoying the peak of human intelligence, morality, and technological advancement.
We currently enjoy an unprecedented standard of living, but we are headed for a grim future. Industrialized nations are riding a shortsighted, greed-driven juggernaut that may have more in common with the Titanic than with the Starship Enterprise. We ought to consider where we’d like to end up and plot a course.
References
1 Pongsiri, M. J. et al. Biodiversity loss affects global disease ecology. BioScience. 59, 945–954 (2009)
2 Keesing, F. et al. Impacts of biodiversity on the emergence and transmission of infectious diseases. Nature. 468, 647-652 (2010)
3 Lynch, M. Rate, molecular spectrum, and consequences of human mutation. PNAS. 107, 961-968 (2010)
Photo Credits:
top: The Daily Telegraph
middle: Luciano Morelli, freakingnews.com
bottom: German History in Documents and Images (GHDI)
Posted by Quinn O'Neill at 12:45 AM | Permalink
Comments
Thus spoke today's Oswald Spengler, and with greater cause, I must admit.
Posted by: Evert Cilliers | Dec 13, 2010 8:43:05 AM
And just think, the most intelligent humans breed the least.
Posted by: Alice de Tocqueville | Dec 13, 2010 11:12:56 AM
Actually, we don't know that, do we? Would it be better to say the most educated breed the least?
Posted by: Alice de Tocqueville | Dec 13, 2010 11:17:05 AM
^ I would call you a racist, but that would be an insult to racists.
Posted by: Marc | Dec 13, 2010 2:14:18 PM
Quinn, I'm tempted to say that this is a bit sensationalist, but the number of variables that the potential outcomes rely on is too numerous for me to confidently judge. Beyond that, I would take issue with two of your points.
First, the idea that "high intelligence" arises rarely is a somewhat confused interpretation of evolution. If we grant that current human-level intelligence is the minimum level by which we would distinguish "high intelligence" then it would seem that given the history of multiple mass extinctions due to severe environmental threats, and the hurdles this imposed on the speed of evolution, than evolution seems to have produced "high intelligence" just about as soon as we could imagine it evolving. If we posit that the minimum types of physical traits requisite for "high intelligence" to evolve are to be found in animals such as primates, cetaceans, and even possibly corvids, (all evolving within the last 50-60 million years) than we have a rather quick timeline given the historic hurdles. If these requisite physical traits, and the environment they find themselves in, are what is required for "high intelligence" then they seem to have come on the scene as soon as the niche was opened up by the loss of the dinosaurs. Now, in a Gould-type of perspective we might say that given the history of the Earth's mass extinctions the odds are against this particular type of evolutionary sequence being reproduced in multiple hypothetical reiterations. But, the fact remains that within the one actual history from which we can glean the tendencies of evolution's paths we do in fact see "high intelligence" arising rather swiftly given the circumstances and physical adaptations required.
The second point concerns the lack of advocacy on behalf of gazelles and rabbits. I would say that this is less a case of anti-human bias in those who would find the slaughter of animals by other humans objectionable, and more of an intuition by these people that our modern level of slaughter is unsustainable, though not wrong in any sort of absolutist sense. This intuition likely also provides the sense that what is previous to humanity is beyond the scope of moral calculations. That only the human sphere of actions is subject to moral judgment, since morality itself is a human creation. As well, I think most who object to other humans slaughtering animals for sustenance are in fact restraining their judgment to those industrialized places where the mass slaughter of animals is seen as unnecessary and no longer continuous with the sustainable, traditional practices from which they were expanded and adapted. And this appears to be consistent with your interpretation that our actions as modern, industrialized humans are not wreaking havoc with our environment and threatening our survival because they are morally wrong or an aberration of "normal" evolution. Instead, these actions are an over-reaching, a gluttony whose motivations are formed from short-term desires with very little mind towards long-term balances of the resources that our environment provides. Sadly, as you've pointed out the environment will eventually, if it hasn't already begun to, provide a check on this pattern of indulgence. Though to my mind the ultimate outcome seems beyond our prediction.
Posted by: Ben Schwartz | Dec 13, 2010 3:02:45 PM
I was under the impression that this sort of genetic change could not occur in such a short timeframe. I believe that many biologists are under this impression as well. What reason do we have to think otherwise?
Posted by: Joe | Dec 13, 2010 3:13:05 PM
I suggest, on my blog, that we name this potential new species now, while we can.
Let us call it: homo inhofe.
http://thepondonome.wordpress.com/2010/12/13/a-new-species-of-homo/
Posted by: The Pondonome | Dec 13, 2010 3:15:57 PM
Human inteligence is the consequence of human evolution.
Nothing else is evolving to human intelligence because they are not humans.
Chimp intelligent is the result of chimp evolution, dolphins, whales etc etc.
Posted by: Will | Dec 13, 2010 6:56:08 PM
I think you're confusing intelligence with knowledge at least once in this piece.
Knowledge - even in pre-history - was cumulative thanks to language. The ability to "pass on" information (hunt here at this time of year, store grain this way, not that way...) made this cumulative information possible.
This has accelerated thanks for the modern flow of knowledge (thanks to the explosive power of the printing press) and the development of the error correcting mechanism that is the scientific method.
But don't confuse knowledge for intelligence. We're still essentially the same human beings as we were tens of thousands of years ago albeit with the atom bomb instead of the bow and arrow...
Lots of animals are intelligent, but (with extremely rare exception) only humans possess the intelligence which produces cumulative knowledge that transcends our biological species (i.e. information which can be passed down outside of our genetic makeup.)
Despite this though, we still seem incapable of thinking past our own immediate needs and wants or those of our immediate offspring. We lack a sense of the "long now" that probably means our society isn't destined for Star Trek, but more likely for The Road. I think it's genetic born out of living red in tooth and claw for so many thousands of forgotten years.
For instance, we know that it's not a question of if a astronomic impact will severely alter and damage earth's global environment, but when... and we have the technology and know how to look out for, plan and either eliminate or mitigate such disasters, but we're doing very little about it... indeed, some of us are so primitive in our thinking that we either question the evidence of previous impacts or cling to the notion that "God is still up there" and that's the type of defense you can't appropriate funding for... (and people who think this way hold some of the highest offices in the most advanced nation on earth!)
We just seem really bad at thinking ahead...
Posted by: mrgoodbar | Dec 13, 2010 7:29:59 PM
@Ben,
When I say that high intelligence arises rarely, I’m referring to the frequency of the occurrence as opposed to its likelihood. That high intelligence (human-like intelligence, that is) occurs rarely isn’t really debatable--it's only happened once. As for the likelihood of it occurring again, or of us progressing to ever greater heights of intelligence, I don’t think we can make a good estimate.
John Maynard Smith made this point in an interview with Robert Wright a few years ago. On the subject of the likelihood of high intelligence evolving, he said, "the only empirical evidence we have is that organisms of the right general kind--bipedal vertebrates living on land that is the right sort of size and so on--existed for over a hundred million years before it came off. So it's obviously not something that's trivially easy.” (I've modified the quote slightly from the transcript to make it easier to read). He wasn’t making the argument that the development of high intelligence is unlikely, but that we really can’t estimate how likely it is. The entire interview is worth watching. It can be found here: http://www.meaningoflife.tv/video.php?speaker=maynard%20smith&topic=direvol
(He makes the above-mentioned point about 32 minutes in.)
My point about the rabbits and gazelles is really a recognition of the inconsistency in my own position. I find the idea of animals suffering in a slaughterhouse disturbing; yet I don’t have a problem with deer being eaten alive by predators in the wild. If I care about animal suffering, then who or what causes it shouldn’t matter so much. What makes the difference, I think, is that animals in the wild have to eat each other alive in order to survive. We’re lucky that we don’t have to behave like savages in order to survive. If we did, we would. And maybe someday we will.
Posted by: Quinn O'Neill | Dec 13, 2010 9:02:07 PM
Many people find the slaughter of food animals objectionable. Yet no one is advocating intervention to save the gazelles from the lions or the rabbits from the foxes.
That's probably at least partly because lions don't specifically breed gazelles that can't survive on their own, keep them in tiny enclosures, overfeed them antibiotics, systematically kill them at ages far below their life expectancy, brand, mutilate, and stress them, and dump their waste in huge pools that degrade the environment. Although they're certainly like the average factory farm in beginning to strip apart at least some of their victims before they're actually dead. Ditto rabbits and foxes.
I agree with most of what you're saying. I am just very tired of people equating factory farming of animals with animals in the wild. It's not the same, because death is not what's at stake.
Posted by: Georgia Claire | Dec 13, 2010 11:50:09 PM
"We’re lucky that we don’t have to behave like savages in order to survive. If we did, we would. And maybe someday we will."
I think the problem is that, without having to, we do behave like savages. Like animals, but without their innocence and without their grandeur.
Posted by: Elatia Harris | Dec 14, 2010 1:37:22 AM
"It's not the same, because death is not what's at stake."
Exactly. When I eat an animal, I am far l less concerned with how it died than with how it lived.
Posted by: chris | Dec 14, 2010 2:15:12 AM
You're quite right, Elatia. I probably should have said "like savage non-human animals" instead of "like savages". We aren't eating live animals, but our behavior can be extremely cruel. That said, savagery is relative. Generally speaking, our species may be the most civilized it's ever been.
Posted by: Quinn O'Neill | Dec 14, 2010 3:33:04 AM
I subscribe to that argument, Quinn. By some metrics, we are certainly less down with wholesale cruelty than we were. Though we are more conscious on many levels than in past eras, we are letting the biggest threats open the way to conditions that will summon back real savagery as a survival skill. Tidying the reception room, letting the foundations of the great house rot. Turning a moral awakening into an ornament that will need to be discarded. How ethical is it, really, to be personally scrupulous but live also in such a way as to build a future that will call our ethics dainty? Guilty as anyone, I only want to know...
Posted by: Elatia Harris | Dec 14, 2010 10:03:39 AM
Quinn,
I appreciate your point about frequency versus likelihood. I should have distinguished those two interpretations of "rare" in the first place. And I'm certainly not one to quarrel with John Maynard Smith. This is the same problem with the "anthropic principle". With only one data set, the use of comparative terms becomes meaningless.
Concerning rabbits and gazelles, I find that the inconsistency you point to (which I often get caught up in) is mostly a function of taking an all-or-nothing (some might say Kantian) stance on particular types of circumstances being morally wrong. And further, believing that you can isolate the relevant circumstances from their respective contexts in order to apply this judgement. This particular instance of suffering having been distilled from two distinct situations: Industrialized slaughter by humans versus animal slaughter in the wild. Yet, if we expand our comparison of the two circumstances to take into account the various different motivations and contexts then we shouldn't have any inconsistency. It's simply different for a modern human living in an industrialized environment to slaughter an animal than it is for another animal in the wild. If not in type, at least in degree. Unfortunately, our tendency to say something like "they are both acts of animal slaughter, or animal suffering", and thus fit for one-to-one comparison, is most often a product of our reductive use of language and not the more robust facts of the matter.
Posted by: Ben Schwartz | Dec 14, 2010 3:25:24 PM
@Ben,
"It's simply different for a modern human living in an industrialized environment to slaughter an animal than it is for another animal in the wild."
This is my perception too. Civilization gives us the impression that we aren’t wild, while morality gives us the impression that we aren’t animals. However, while human societies are more complex than those of other animals, they are no less natural. And the moral sense, like other traits of people and non-human animals, was selected by nature--not by us. Despite what we may perceive, we are as much a part of nature as any other living thing.
Posted by: Quinn O'Neill | Dec 14, 2010 5:48:06 PM
I was under the impression that this sort of genetic change could not occur in such a short timeframe. I believe that many biologists are under this impression as well. What reason do we have to think otherwise?
Posted by: Joe | Dec 15, 2010 1:16:21 PM
Interesting article Quinn.
Obviously, there are an infinite number of possible futures for us on this Titanic rock of ours but we are, at least, in a position where we can use our imagination-radar to plot a safer course for ourselves. (I hope that metaphor isn't as unwieldy as I suspect)
If your worst case does arise though it might not turn out all that bad... Perhaps tens of thousands of years after this new homo-troll appears, levels of pollution etc will revert to a more healthy level and slowly these creatures (or ones evolved from other primates/cetaceans/corvids) will oh. So. Slowly crawl back to a stage of high intelligence.
It's all life. It won't matter so much to me how the atoms of the universe come together to recognise themselves, as the collection of molecules I call 'me' will have long dispersed anyway.
Should some set of events take place that lead to this new civilisation though I would want at the very least for them to be able to read our books, listen to our music and laugh at our mistakes. I wonder if anyone is storing our knowledge in some undecayable manner? As our stone buildings and paper books and plastic hard drives will crumble to dust long before a future brainy-cockroach archeologist will find them.
Anyway, I'm a optimist in many respects and I believe (with a thin but hope-filled sprinkling of evidence) that as the human populace becomes more urbanised and educated birth rates will drop and our world population will level out somewhere between 8 and 9bn. Couple this with better ways of creating energy and more sustainable modes of farming (less meat more insects and veg? Yum) and we might just make it through to the fun galaxy exploring stuff.
Not easy to get there mind...
:)
Posted by: weavehole | Dec 17, 2010 11:34:55 PM
Post a comment