Juan Enriquez explores the possibility and inevitable risks of human speciation.
While we humans like to think of ourselves as wildly diverse, any alien coming to Earth and systematically cataloging its life forms would find us singularly boring. There are many, many species and subspecies of birds, bees, bacteria, and cats, but humans are almost identical. The variations between people occur in only 0.1% of our genomes.
This is really odd. Natural selection favors more variation because it provides the ability to adapt to various ecological niches. Variation leads to long-term protection and survival under different circumstances, like plagues and climate change. When you depend on one and only one variant, you can end up in the midst of an Irish potato famine. In strict biological terms there is not nearly enough human diversity.
We have not experienced even small tastes of true diversity for millennia. Although there were once 30-something species of proto-humans, we have not seen or mated with one even mildly different from us for a long time. In fact, we don’t actually seem to like the idea of having more human diversity. The notion of making small changes to a fetus elicits horror and revulsion. We probably would be quite uncomfortable living side by side with restored and revived variants of our proto-species. How would you feel about the (literal) Neanderthal dude next door?
But soon we’ll need to cope with true diversity within our species. We are not just talking variants of ourselves that Homo sapiens could mate with.
The era of space travel, and potentially space colonization, may just force the issue of true speciation. Launch a human body into space and it dramatically decays. Almost all long-term astronauts come back severely damaged by their jaunts, in their vision, hearts, bones, brains. So if we are to leave this place, we are going to have to seriously reengineer the human body, very deliberately, to induce the kind of evolutionary adaptations required for surviving higher radiation, different gravity, more extreme environments. Those engineered humans would be diverse, and the differences between them and humans of today would increase rapidly as successive generations of them got further and further from Earth and adapted to truly different ecosystems.
Even if we do not begin to colonize space in the near future, the human genome will diversify by other means. As more and more gene therapies come online to deal with horrid diseases, the tools necessary for such procedures will become more standardized and widespread. People will use these tools to engineer their own genes and organs, and they won’t do it the same way everywhere, especially if different countries adopt different regulations, restrictions, and incentives.
Historically, when we have encountered perceived human diversity, it has not usually ended well.
Symbiotic implants may also splinter Homo sapiens. Already, engineered limbs are giving athletes abilities beyond those of “normals.” Some implants will give people super hearing, in tones we cannot perceive, or super sight. But only some humans will have these powers, especially if the upgrades are expensive.
Historically, when we have encountered perceived human diversity, it has not usually ended well. For millennia, minute variations in skin color, height, or eye shape have justified slavery, serfdom, and other forms of oppression. Everyone knows “that” group is different, and therefore “that group” should be treated differently.
Now we’re on the verge of having humans emerge with much bigger differences. True diversity potentially implies different life spans, bodies, and intelligence. Given our very checkered history of how we have treated “others,” it is high time to consider the consequences and rules for emerging human variants. We may want to think carefully about the rights and protections we provide to existing species that demonstrate different forms of intelligence, like apes, octopi, dolphins, and whales.
How we treat them and interact may be a blueprint for the customs and laws we will develop as Homo sapiens begins to speciate.
Excerpted from the book Neo.Life: 25 Visions for the Future of Our Species.