This video is sponsored by CuriosityStream. Get access to my streaming video service, Nebula, when you sign up for CuriosityStream using the link in the description. About 300 million years ago, there existed a small shrew-like species who really wished the Earth wasn’t so full of big, pesky dinosaurs, and while that creature is long extinct, its descendants now dominate the planet. As it was with them, so it likely will be with us in the future… and maybe in hundreds of years, not hundreds of millions. There once was a single mammal, possibly the Morganucodontids, a creature resembling a mix of rat, opossum, and shrew, from which every future mammal descended. Back then this critter and siblings were a single species and as far as we know the only mammals, so mammals would have been a species and not a class, yet. Millions of years later that species would have become a genus
composed of many species, millions more and it would have become a Family composed of many genus each of many species, then eventually an Order composed of many families, and finally a Class. That rat-like ancestor of ours existed just a few hundred million years ago, when the Universe was around 2% younger than it is now, and it would seem like it will not take nearly that long for humans to split out into a Genus, then Family, then Order, then Class all its own. As we spread out to the stars, those alien environments should change us. Even without cybernetics, genetic engineering, and distinction blurring concepts like mind-uploading and artificial intelligence, humanity as it is now would seem but a temporary thing in the long run. But we probably do not have to wait eons for such divergence of the species, not with things like cybernetics and genetic engineering, both likely becoming big factors in our civilization before this century is out. And this is where we get to the concept of transhumans
and eventually post-humans, those creatures and people who might have us as common ancestors, but are radically different from us and each other, human clades grown into their own species or even further apart. We’ve talked in many past episodes about various ways human beings might alter ourselves or our offspring, to adapt to the various environments and new tasks we’ll face as we spread across the solar system and galaxy. Today, we’re going to look at relations between those various types of post-humans, particularly the degrees to which they might coexist, come into conflict, or just physically separate from one another. We’ll also look at the extent to which they’ll biologically separate, eventually into forms that can no longer breed with one another – qualifying them in any reasonable taxonomy as entirely separate species. But
this examination of the post-human, multi-species community won’t be complete unless we also pay a visit to the many species that humans will eventually construct--animals we’ll uplift to human intelligence and robots we’ll make sentient and sapient from scratch—species that we’re currently trying to create even now. This will be a lengthy conversation so now is a good time to get whatever analog to a drink and a snack is compatible with your biology and settle in for a while. At the core of all of this is the notion of species and speciation. We’re going to challenge and bend the traditional idea of a species, but the concept of speciation will still apply so lets review that. Species is the lowest level of the traditional taxonomy that’s been used to classify plants and animals since the 1750’s, with higher-level categories called genus, family, order, class, continuing up to phylum, then kingdom, then domain, under the umbrella of life. We would be in the chordate phylum of the Animal Kingdom of the Eukaryotes Domain... those life forms whose cells
have a nucleus, and we would probably need another tier above that specifically for Earth-based life, since cells and cells with nuclei might be fairly common off Earth but wouldn’t be related. As mentioned there are a lot of other classifications in there too, subspecies, subkingdoms, and so on, with often only loose agreement on what they should be or where to draw dividing lines. We should always remember that any taxonomy, whether it’s of living things or celestial objects, is an attempt to fit things into categories that people invented, based on things they’d observed up to that point. Discovering new things after you defined categories is how you end up in long discussions about whether Pluto is a planet or dwarf planet, or frustrated at the platypus for not quite matching the criteria for being a “mammal”. And when you do finally resolve those controversies, you haven’t actually learned anything new about Pluto or platypuses, you’ve only changed the definitions of words.
One of the traditional criteria for designating two types of creatures as different species is that they couldn’t interbreed and produce fertile offspring. So for example, horses and donkeys are separate species even though they can produce mule offspring because the mules are infertile, incapable of reproduction. And in fact we use mule as shorthand for any infertile cross-species hybrid. But this part of the definition of species has been seriously challenged by our later discovery of quite a lot of successful interbreeding by creatures we already called separate species. For example, modern humans and Neanderthals have always been
considered related but separate species, but it’s now pretty clear that they frequently bred with one another, swapping DNA many of us still have. A more current but still rare example of such cross-breeding is between polar bears and grizzlies, as environmental change brings them into each other’s territories. But while being able to cross-breed is no longer a sound criterion for putting creatures in the same category, it’s still pretty reasonable to say they’re separate if they can’t cross-breed at all. But then we also have to re-examine what counts as being “able” to cross-breed. Genetic manipulation will enable us to hybridize creatures that absolutely would
not be able to in nature. And at the extreme, digital beings like AIs and downloaded humans have a genetic code of sorts of their own, and we’ve already created novel AIs by combining features from several AIs with desirable performance traits, which is actually a pretty good definition of the word breed. An important notion for this discussion is speciation, the formation of a new and distinct species. In nature this can occur from species interbreeding or more often from a single species splitting into multiple species. It’s very often driven either by environment changes that must be adapted to or by migration into a new environment. So for example, a tribe of monkeys living mostly in the trees might find themselves needing to come down from the trees to forage for food in open grasslands.
In time, the monkeys best at surviving in the grass will roam farther from the tree line, practice standing on their hind legs so they can see over the grass, and eventually adapt to that lifestyle so well they don’t see their cousins back in the trees much anymore, let alone breed with them. They evolve on their own separate path, and a new species is born. The same thing happens when grizzlies in the cold far north suffer a mutation that makes them albinos with fatty skin, and they find they can now survive on the vast snowy plains ever farther north than their cousins can. Notice that in both cases, there is a feedback loop, in which small differences in physical traits help them adapt to a new environment, which leads them to migrate farther into that environment, which takes them physically farther away from those that lack the adaptation trait, which exacerbates the difference in traits. The two groups could have interbred all along, but they didn’t because they were physically far apart, and so they also drifted genetically apart. Feedback matters a lot in our discussion too, as an example, organisms might speciate but also converge in weird ways. A person might upload their mind to a robot body, or an artificial computer mind might upload their mind to a cloned or biologically engineered body, and either might have progeny who do the reverse, returning to the original organism after a few steps, while their cousins might have diverged in physical form in just a couple generations by more than a million natural generations could have.
But for future humans, gradual evolution will probably be far less of a force than sudden deliberate changes brought about by biotechnology, and those same technologies might make crossbreeding possible. So too, they might matter less. It is not impossible to imagine a human marrying an android, with whom they could never naturally breed but which leaves some questions about where and how the hybrid offspring would live. It is not just that we have to ponder all these various post-human groups and how they would interact with each other, like how the hive mind gets along with the super-intelligent dogs, or how the latter don’t get along with the super-intelligent chatbots.
Nor is how the uploaded minds get along with artificial intelligences, or how cyborgs get along with the AI who download themselves into synthetic biological bodies. Instead, ultimately, it will be how a thousand flavors and blends of each get along. But for simplicity and in the nearer term, let us ponder how each of these major groups will be adapted to their environment, and how this will preclude breeding. We can imagine some of the more probable genetic divergences in humans, be they long term natural adaptations or accelerated by biotechnology--for example, alteration to live in low-gravity, such as on the Moon or Mars, or even essentially no gravity, such as on most asteroids or in non-rotating space habitats. See our episodes on Life on Low-Gravity Planets or Zero-Gravity Civilizations for further discussion of those. Of course many worlds might have higher gravity
too, and we can see worlds with different atmospheric densities and compositions which might require extensive engineering to make livable. We can imagine eyes adapted or altered to see in dimmer or brighter light, or in frequencies of light invisible to us now. Of course we can imagine goggles or contacts or even cyborg eyes performing that role too, and a critical concept of transhumanism is that these sorts of technological integrations can be viewed as a part of speciation in the same way as a genetic mutation. All of those examples also illustrate how physical separation will accelerate the genetic separation. If you are genetically adapted to be at home on a high-g planet with visible light and a slightly acidic atmosphere, you probably won’t spend much time hanging out with attractive people who live in zero-g, breathe Earth-like air, and see in dim infrared. Even if you could overcome the logistics, mate with them, and produce fertile non-mule offspring, those offspring will probably not inherit the correct full set of adaptive genes to be able to live in either parent’s environment, so they’d either need cybernetic implants to help them or a special environment customized to their needs. Of course, the mixing of genes doesn’t
have to be so haphazard as it is in nature. Just as biotechnology will enable rapid adaptation, it could also enable controlled, safe interspecies cross-breeding, and we’ll return to that topic later. We can also imagine a hive organism, such as the Star Trek Borg Hive Mind composed of many different species, and yet itself only a single organism, and this would be an example of a post-human. So too would a person who was part of a Hive Mind, or an artificial intelligence who chose to join a hive mind, or which had hundreds of robot bodies it operated, which is the opposite of a Hive Mind in many ways. What about a person whose great-grandfather was a cat, who had been genetically modified to be smarter, who was followed by a cat, the grandfather, who was modified to be even smarter, near human, and have hands rather than paws, who was followed up by something like a cat human-hybrid, having fully human intelligence and humanoid form, who fell in love with and married a human girl. Finally, their child opted to be altered to be entirely human
in DNA and appearance, even while many of his cousins still dwelled in the ancestral home as regular or slightly modified cats. This is the potential awkwardness of the post-human family, not to mention confusing genealogies. Your neighbor comes by for a visit and you have to introduce your grandmother to him as the cat on their lap they’ve been petting. Or that your step-brother is the car in the driveway, who is also part of a hive mind, or that you actually have seven biological parents, each of whom contributed DNA to you, that you were grown in a tank, and that you also regard the House AI as a parent, as well as the super-intelligent Dolphin who has been like a mentor to you since you were a kid and oversaw your doctoral thesis when you attended the University where he’s a professor. It’s important to understand that a species can split even if the product species aren’t physically separated. In nature, a species can split simply because different members adapted
to different ecological niches. Predators who take down prey and scavengers who clean up the scraps often descend from the same species, and they’ll develop traits suited to their niches a lot faster if each group breeds among themselves even while they coexist. They will do this even more rapidly if they can add those traits when they desire them, and a group already used to a little of some new trait, like the ability to see infrared, might be more inclined to embrace those who decide to add in other sensory augmentation and mental augmentation and alteration needed to handle and use those senses. Cyborgs may be heavily genetically modified to accept the synthetic interface and to not have bodily needs like physical touch and diverse nutrition. They may often be Frankenstein entities, using entirely different DNA for given
limbs and organs. Even if we tried to force the interbreeding with genetic manipulation, the cyborgs might simply lack the genes to create intact non-cybernetic living things. Hive mind people will probably require similar modification, at the very least a brain interface that connects their minds in ways that ours can’t, that makes them a true hive rather than a mere close-knit community. So where interbreeding people adapted to different
physical environments might leave you with offspring adapted to nowhere, crossing hive- with non-hive-humans might leave you with people who can’t function in either social environment. Even if such interbreeding is still physically possible or can be forced in a lab, it probably won’t take place often if there is not some compelling reason to do it. Humans were probably able to adapt to cold hard northern environments much faster by breeding with the brawny cold-resistant Neanderthals who were already there and adapted, even if those brutes weren’t very bright. But it’s hard to imagine what similar issues future humans with biotech would solve quite that way, and we will be exploring various biotech options in a couple of weeks. We might also ask which groups will be most numerous, to form the new majority or major factions at least, and that may depend heavily on which human adaptation will best allow people to spread quickly across the galaxy and colonize new spaces? The ability to withstand cryosleep, for instance, might be partly genetic, either natural or engineered, and it might be an advantage big enough to make such folks the majority of interstellar colonists. So might the ability to quickly erect livable habitats, like the folks adapted to zero-gravity can, since they need not go to the effort to build large rotating habitats.
Or the ability to breed quickly, an option artificial intelligence would seem to have or those who embraced some equivalent to cloning and duplication, of mind or body. Many worry that humanity might face overpopulation, but many also worry we might see our birth rates drop below replacement levels, were this concern to materialize as a threat to our continued survival folks might embrace creating folks by more artificial and rapid means. Indeed we might see techniques that resulted in very short childhoods become popular, while on the flip side, parents might embrace technologies that extended childhood to several decades rather than one or two. Such groups might not get along with each other very well either.
Which sort of traits would let us best spread out to the galaxy? And could regular old humanity do it? I mentioned how some of these traits might be advantageous for colonizing space and thus contribute to a given faction becoming more numerous. Now a given faction colonizing space more aggressively than others and growing does not mean they themselves are not diverging too. Indeed the simple limitation of light speed for travel and communication would seem to ensure divergence and a lack of cohesion, so we are not really asking here what traits might let a given type of transhuman or posthuman dominate the galaxy as some cohesive empire. That said, one trait that might do it isn’t about how quick they could get out and colonize, but how slowly they diverged or how devoted they were to remaining united. A posthuman clade modified to be obsessed with no further alterations - which
regarded its current form as perfect or nearly so - or which was obsessed with unity even across interstellar space, might maintain some sort of interstellar empire. After all, shipment or transmission of “approved” DNA wouldn’t be very difficult. They also might make for very worrisome neighbors, though this trait need not necessarily be combined with xenophobia or hostility, or aggressive recruitment like we tend to assume Hive Minds would engage in. Of course folks fixated on avoiding divergence or dissension, friendly or not, are often the opposite of expansionist. Isolation in nature can cause an ultra-niche species, like some creature that is ultra-adapted to one specific diet in one specific climate and defense from one specific predator. However in artificial rather than natural circumstances it can make it easier to avoid drift, genetic or cultural, and so folks looking to maintain some trait without divergence or drift might seek out circumstances or environments that favor that trait heavily, or even create them. That’s a topic we could probably spend an
entire episode on all by itself and may do so at some point in time, but an environment where poking noses into holes always gets them bitten discourages curiosity not just genetically but culturally too. Either that or the evolution of a longer and tougher nose. If you’re trying to discourage lots of socializing in person, then setting up your colony in some radiation blasted environment and releasing tons of infectious diseases is a good way to encourage folks not to go outside and play or hang out together. Those are extreme and simplistic examples but if your goal is to keep some trait around for millions of years, you might go to such lengths.
There’s always the question of if old humanity will go extinct and in some ways the answer is yes, as we go extinct every generation, that original first mammal, some sort of rat-possum-shrew-thing, is both gone and everywhere, how can something be said to be extinct when its descendants dominate virtually every ecological niche? Should we care about baseline humanity going extinct in favor of a trillion diverse clades we created anymore than we care that you or I personally will not be around? And of course we might be around, you and I, and the most important trait for interstellar colonization, fundamentally, is longevity. This can mean either personal longevity so that you reach the stars, or cultural longevity which is accomplished by being able to pass your culture’s way of thinking and doing things onto your descendants or successors. Even ignoring the huge travel times, colonization of a system is a long and deliberate process. This is why another important trait in natural selection is the urge to grow and expand. This is true of species taking over a tidepool or a galaxy, because an organism lacking this trait is not one claiming new niches or even maintaining control of old ones.
We can talk about post-humans replacing us but you or I might end up as those post-humans. Life extension is likely to be one of those critical technologies we discover before going truly interstellar, in large part because its likely a lot easier to get volunteers for interstellar travel when a century long voyage is not something that you wouldn’t survive to finish and be able to do something else when you’re done with the trip. The prestige and curiosity of interstellar travel might bring on volunteers when it’s new, to fuel that first dozen colonies, but we need hundreds of billions of such colonies to fill the galaxy and we will probably get them regardless but they’d be a lot easier to find if the volunteers can expect to live many centuries or millennia. At this point, this person who is baseline human except for not aging may or may not be able to have other transhuman or post-human alterations as time goes by, but it is hard to argue that you or I, as a post-human a million years old, is less of a human than someone who is naturally descended from regular human reproduction for a million years or someone we whipped up a million years from now with purely modern DNA. Some human-intelligent cat-person made in 50 years or some android might feel, with some cause, that they are as much a legitimate spokesperson for modern humanity as those two cases I just suggested too. We should
also keep in mind that genetic divergence into many groups might not mean physical separation. We are a specialist society and we might diverge into castes with genetic differences, a popular notion in science fiction which sometimes shows alien species divided into various sub-species who specialize at given tasks. I suspect they will be around though, baseline humans of the modern period. They may not be competitive in a given environment but neither are most animals in a human-dominated environment but we still preserve them and a few dedicated worlds out of countless trillions used for keeping the 21st century human around is plausible enough, especially given that these need not be real planets, they might be simulated worlds entirely on some computer buried in some post-human civilization’s bunker-libraries become zoo.
And those post-humans are human descendants whether we made them in a lab, on a computer, or more traditionally. It doesn’t matter if we intended them either or if they were the creation of one of our creations or one of our creation’s creations, anymore than it matters if that shrew-like critter from 300 million years ago meant to make us. Indeed one might argue a machine mind you made intentionally has a better claim as a true successor than some critter a thousand generations of mutation removed from you. One way or another, there probably will be folks around claiming to either be human or their true and legitimate successors, whether they’re hyper-intelligent brains on a computer the size of a planet or some nature preserve set aside by such a creature, in real or virtual space.
Of course it's always possible we already are in such a preserve and just don’t know it. So this was one of our shorter episodes, but if you’re looking for more information on Transhumanism, there’s a great episode by Jason Silva on Transhumanism over on CuriosityStream, and a point he raises in that is that humans use tools and they almost become appendages to us. That can be fairly literal and is something we’ll be looking at it in our Biotech episode in a couple weeks, but one thing we didn’t talk about much today is the mental changes that might come with post-human or transhuman existence so we’ll spend a few minutes on that in an extended edition of today’s episode over on Nebula in a segment about life in the fast lane and what it means for speciation. I wanted to thank Curiositystream for their help growing Nebula, and our viewers even more so, since they’ve stuck around as we’ve continued to grow and improve it until its started making waves and bringing in ever more creators who want an alternative to Youtube, and if you’re interested in helping out the show while getting to see all our episodes ad free, and some with extended editions, like today’s, you can join Nebula.
Now you can subscribe to Nebula all by itself but we have partnered up with CuriosityStream, the home of thousands of great educational videos, to offer Nebula for free as a bonus if you sign up for CuriosityStream using the link in our episode description. This means you can watch all the amazing content on Curiositystream, like Jason Silva’s discussion on Transhumanism, but also all the great content over on Nebula from myself and many others. And you can get all that for less than $15 by using the link in the episode’s description. So we’ve got a Livestream coming up this Sunday, where we’ll be taking your questions live in the chat, Sunday, April 25th, at 4pm Eastern Time. Then we’ll close out the month of April with
a look at how Multiverses and Quantum Mechanics might impact the Fermi Paradox. That will finish out April but May will be jammed packed, as we look at Biotechnology, Alien Languages, Laser Pistols, Lightsabers, Arcologies, Solar Flares, and Simultaneous Evolution. If you want alerts when those and other episodes come out, make sure to subscribe to the channel, and if you’d like to help support future episodes, you can donate to us on Patreon, or our website, IsaacArthur.net, which are linked in the episode description below, along with all of our various social media forums where you can get updates and chat with others about the concepts in the episodes and many other futuristic ideas. You can also follow us itunes, Soundcloud, or Spotify to get our audio-only versions of the show. Until next time, thanks for watching, and have a great week!