I would like to propose two ideas as to the direction of future human evolution.
I am assuming away what I consider to be the most likely direction, namely purposeful manipulation of our genes. Rather, these scenarios are based on continued technological development which, for whatever reason, doesn’t meddle with our genome.
Genes for Wanting Babies
Observe that modern technology largely breaks the link between physical fitness and number of fertile off-springs. Rather than fitness, the most important factor determining the number of off-strings is… how many off-springs we want to have.
Humans are hard-wired to want to have babies, but the degree to which that desire burns in us varies from person to person. While there is very large cultural contribution to that desire, some of it is also genetic.
In the long term, the stronger the desire to have babies, the more babies you will have.
Ergo, the most important selection pressure would be towards strengthening the genes controlling desire to have babies.
Accumulation of Bad Genes
The process of natural selection relies on mutations. Most mutations are bad, a small minority are good (as in conferring superior survival probability). In a steady-state, most bad mutations are eliminated as individuals holding them die quickly.
Modern medical technology allows more and more people to survive and have children that, under “natural” conditions would have died. I, for example, am short-sighted. It is hard to see how I could have survived in a hunter-gatherer society. Nowadays, on the other hand, my ability to bring about off-springs is completely unaffected.
Over time, the pace at which bad, (but thanks to medical technology non-fatal) mutations accumulate will far exceed the pace at which any good mutations occur (or occurred in the past). Thus humans will experience rapid “devolution”, with the quality of our genetic make-up deteriorating down to the level supportable by available medical technology.
Asymptotically, human population will be dominated by genetically-defected baby lovers.
How do you reconcile this with the observation that as the education and quality of life/living standards reach a certain level in developed societies, birth rates plummet?
Culture changes much more quickly than genes, thus in the short-term, cultural changes easily trump genetic changes.
In an absolute sense, culture can continue to trump genes. It is possible, for example, that cultural aversion to having children will become stronger and stronger such that even people with relatively strong genetic disposition to having children will refrain from having more than 1-2 per family (sort of like China’s one child policy).
In relative terms, however, within a given culture, those that want more babies will ultimately take over.
I think the assumption of steady state technological development is perhaps the weak point in your argument. Evolution is happenstance and what mutations survive and those that don’t are always in response to environmental conditions. The idea that evolution will be thwarted by man-made technology is valid, but then the issue is no longer about evolution but man-made engineering. You’re short (near) sighted, but through technological advances, the genes responsible will be identified and corrected. There will be no devolution. That is the vague promise of technological “progress”. The possibility of a crude Botany Bay scenario is already with us, the question is, can we maintain enough world stability to perfect genetic engineering? The jury is out, and any predictions are unreliable.
It is interesting because the real question is can we defeat evolution as the prime mover?
I should have clarified. I don’t necessarily think that our phenotype will deteriorate. The practical expression of the genes will, thanks to advancing medical technology, remain as useful and fit to our (evolving, self-created) environment as ever. We will, however, become progressively more and more dependent on medical technology (and technology in general) to our survival, not just in the numbers and at the standard of living to which we are currently accustomed (we are already there in that sense), but even in small numbers and at primitive standards of living.
Our relation with technology, from being optional, will become essential. We won’t be able to survive as individuals without it.
Having said that, I have no doubt that the desire to positively manipulate the genes of our children, when coupled with progressively safer, more effective and cheaper technology, will overcome any legal or moral concerns, leading to the practice being common-place.
I think it’s possible that technological advancement with respect to health will become technological dependency, which could cause a widespread future catastrophe - though I don’t think this is, in essence, any different than how other species may have become extinct. The only difference is in the particular manner in which it might happen. Dependence on something undependable is all it comes down to.
My point of view is a bit different from a strict genetic POV. I see two futures for the human race also, but driven by either expansion, or conservation of resource. They could co-exist frankly.
(1) Space-going. Biospheres have already been built and tested with human occupants. They are natural/technologic chimera self-contained ecologies - everything recycled in a closed loop. Whole working enviroments modelled in minature from swamp-grass to hummingbirds.
The speed of light and probable impossibility of artificial gravity, will doom a few generations at least to llives led completely zero gee during transit between the stars - travelling in huge armoured biospheres. The phenotype will be thin and spindly, and live together in groups of 150-200.
(2) Virtual. Depending on how the population rises, and how our natural resources and methods of power generation fare in the future, there will be a time of lack. Best case scenario we invent something along the lines of warm fusion (if not cold) or sling a Dyson Sphere around some portion of the sun, throw away the birth control pills and make merry. Worst case scenario we get stuck with fission, and start running out of water. And everything. At which point we’ll be faced with either losing a huge chunk of the world pop. to mal-nutrition, war, disease whatever, or find some way to reduce an individual’s need to as close to zero as possible. The brain runs off 40% of the body’s energy, so we could save 60% by cutting off their body, and giving them a virtual one. Which lives in a giant multiuser domain on the net. Sims would become reality.
Well, if you’r going to separate heads from bodies, I have a list of people I’d be willing to volunteer… Star travel would be multi-generational, but gravity could be supplied via a flywheel arrangement much like 2001, A Space Odyessy. So the phenotype wouldn’t have to change, even over thousands of years on a starship. At this point, I think we’re in a race to see whether we can actually get enough people into a space environment or whether we’ll sink back into the ooze incapable of reaching space from profligate destruction of our resources. It could go either way. The Diaspora may not be our future…
Could be I suppose, but if you’re gonna spend your whole life in space, never setting foot on a world with gravity that would squish you, why bother…? Waste of fuel to spin the ship up to gravity-simulation conditions, waste of fuel to keep it there. Waste of nutrients to build up a skeleton and musculature you’ll never need to depend on for mobility…
Hmmmm, then why go to the bother of star travel in person? That’s what robotic probes are for. We could just as easily send out a thousand robotic adventurers who would send us a postcard now and then. “Having a great time, wish you were here.” The only reason I can think of for corporeal travel is to move from one gravity well to another. I’m not suggesting that becoming a zero-G space creature isn’t our ultimate future, but if space is to be our home, then we let our machines do the dirty work of investigating planets and stars.
I don’t have anything concrete in mind. The ideas came to me when I considered different speculations about the future of human evolution, speculations I considered misguided (e.g. the elimination of unused physical features, or extrapolation of past trends such as growth in brain mass).
Additionally, I think these considerations may play a part in a potential ethical debate regarding purposeful manipulation of human genomes.
You’re right of course. But say one of our probes radio’s us and says “hey boss, we done found a really great planet fer youse”, we still gotta get there. At sub-light speed. It’s two years to mars for god’s sake. 200 years to andromeda. Then you’ve got terraforming, ecological restructuring etc. If you have a mini-world already in space, why fuck about…?
Better would be to (genetically/technologically) engineer/augument ourselves to fit a new world. That would only take nine months, and 15 years of growing up.
Better still, would be to radio our ‘neurologic soul’ as a pattern at the speed of light, direct to our friendly robot probe. If that’s within the realms of possiblity. Mind you, that would be one hell of an e-mail attachment. You might also need to commit suicide on Earth I suppose, at the instant of transit. But then, if everybody’s living in virtual land on Earth by that time, then it wouldn’t make a difference.
That made me laugh so hard, I was afraid I woke the neighbours in addition to my family
But like it has already been mentioned, perhaps we would not be dependent on the natural processes for the genes of the future generations. We may be able to mix and match genes of one’s chidlren (it is anyone’s guess how parenthood will be defined under the circumstance ) by taking them from the available gene pool or even actually creating genes that don’t exist in the gene pool of the earth (all species included). When it comes to that stage, the baby-lover gene can be incorporated as need be.
I am thinking of a scenario like Aldous Huxley’s “Brave New World”, where the different castes (Alpha, Beta, Gamma and Delta) are genetically determined instead of being brainwashed into the caste after being naturally born.
So I predict the exact opposite, genetically perfect with baby-lovers in the right proportion (to take care of the babies that will be created)
Yeah, I see that too. I also see increasing computer-assisted ‘framing’ of our general perceptions. Like a head-up display. Imagine if you looked at something, and a chip/camera combo either in you glasses, or lapels, or just stuck in your head, automatically scrolled up it’s dimensions, specs, got ready to help you to draw it say - by projecting an outline over your view of a sheet of paper. Say you looked at a sheet, or a screen of numbers, it would automatically suggest ways of tabulating them, relating them, crunching them. Auto-translates of signs, auto-translates of films.
As you’re reading, or writing, definitions flash, antonyms, synonyms, rhyming dictionary, suggested words etc.
Info-clouds halo’ing the people you meet’s heads.
Endless possibilities. In the future most of our education will probably consist of learning how to find information, how to relate things to other things, and how to manipulate information, rather than the facts and figures approach we have these days.
But this is already happening where computer/internet connections are strong. I question that it will be the preponderance of future education. The finding of information has always been a growth factor in being considered “educated”. The more information there is available, the greater the need and time spent mastering our personal “search engines”. But just what is information? Answer: Facts and Figures. So who will produce those facts and figures? Answer: Someone with education in facts and figures. So I really don’t see much change in overall education efforts. I agree that tomorrow’s students might be a bit more shallow on the facts and figures end and heavier on the search engine side, but I don’t see much of a broadening of education among the folks. The mind can only absorb as much as the ass can stand, and until there is greater capacity, it’s unlikely that educated humans will be all that much different than today’s version.
Star travel would be multi-generational, but gravity could be supplied via a flywheel arrangement much like 2001, A Space Odyessy. So the phenotype wouldn’t have to change, even over thousands of years on a starship. At this point, I think we’re in a race to see whether we can actually get enough people into a space environment or whether we’ll sink back into the ooze incapable of reaching space from profligate destruction of our resources. It could go either way. The Diaspora may not be our future…
You might also need to commit suicide on Earth I suppose, at the instant of transit. But then, if everybody’s living in virtual land on Earth by that time, then it wouldn’t make a difference.
) by taking them from the available gene pool or even actually creating genes that don’t exist in the gene pool of the earth (all species included). When it comes to that stage, the baby-lover gene can be incorporated as need be.