Humans Are Evolving Right Before Our Eyes on the Tibetan Plateau

Only if giant thumbs are useful in using tinder to reproduce more.

John Hawks, a paleoanthropologist, regularly makes the point [0] that human evolution has accelerated enormously in the last 50k years.

Lactase metabolism is new, in the last 19k years. European skin colours and blue eyes appear to be very recent too, maybe 3.5k years.

Almost certainly there are all kinds of super interesting human evolutionary changes that are occurring now, with our huge population that won’t be visible for thousands of years…

[0] at least since this https://johnhawks.net/weblog/our-new-paper-on-why-human-evol...

Among them, eventually, will be modern medicine if we manage to preserve it long enough and share it widely enough.

By suppressing the consequence of genetic predispositions and vulnerabilities, it lets those genes propagate more freely and invisibly than they would have been doing before. It helps individuals and communities today in a way we can't possibly refuse, but sets up the species to become perpetually dependent on an elaborate, brittle medical infrastructure. Genetic engineering and eugenics could eventually address that, but those invite scifi horrors of their own. We seem to have set ourselves into a bit of a trap.

If you look at the complete collapse of fertility rates in the developed world, that is probably the strongest evolutionary pressure humans have faced for millennia.

It is a bit weird to me that the scientific press doesn't talk more about how evolutionary pressure applies here. I think that people are wary to talk about this because it can end up sounding like social Darwinism, or that they believe "Idiocracy" was a scientific documentary.

But it's inescapable, for example, that education rates are now strongly negatively correlated with fertility. While "level of education" is obviously not inherited genetically, I don't think it's too much of a stretch to hypothesize that genetic factors play a role in someone's educational attainment. And, currently, the more education you get, the less likely you are to reproduce (statistically, of course).

Sex evolved to feel really good because for most of human history having sex would usually, eventually lead to babies. Reliable birth control has fundamentally broken that link. Similarly, when a major factor preventing you from reproducing was starving to death, being smarter or cleverer was an evolutionary advantage. I'd argue that advantage no longer exists.

Another simple anecdote: I recently went to my uncle's funeral, and his family was very religious (Catholic). My father, on the other hand, rejected religion and raised us all atheists. My father has 6 descendants, my uncle 24. Again, "religiosity" is not a genetically inherited trait, but I think it would be foolish to believe genetic predisposition plays 0 role.

I say all this just to highlight that, eventually, the "collapse in birthrates" will take care of itself - people with a strong desire and ability to procreate will outcompete, at least in terms of offspring survival, their peers. This will have a huge, profound effect on world society that most academics are too scared to talk about.

The biggest thing we're doing now is accumulating a huge amount of genetic diversity, full of all sorts of novel mutations and interesting admixtures.

It's hard to know what genes or traits will be advantageous over the next centuries. The biggest place where our technological advantage still has large gaps that our biology can compensate is disease, and there it's almost random -- a gene that results in a novel protein which is normally advantageous or disadvantageous might have the opposite effect if it makes you exceptionally vulnerable or resistant to a new disease.

I could see plastics, chemicals, for-ever chemicals and in general various pollutants leading various pressures on reproduction. So on medium term there could be pressure for genetics that handle those better.

Ability to write good dating profiles which appeal to the algorithm.

The primary "pressure" at the moment is to develop species-level self awareness to stabilize the planetary life support system before we crash civilization.

I’ve heard human jaw muscles are becoming smaller and weaker as there’s less need to chew for prolonged periods of time.

Not GP. This is not evolution, every human is like a lottery ticket, it doesn't change once you draw it. The system "evolves", not humans. Every human is merely a data point (a vector if you will) in this simulation.

But there are nuances to that.

I know several people who have escaped a war-torn country and had a successful life elsewhere, instead of getting affected by military propaganda, and possibly losing everything just because of other people's territorial conflicts.

That’s a pretty binary way to describe a spectrum of behavior. The stereotypical sniveling coward, sure, he’s probably not going on a lot of dates but what about someone who’s prudent or careful about the risks they take?

One especially big confound here is remembering the distinction between having sex and having children. From an evolutionary standpoint, the latter is the only thing which matters and unlike animals humans have contraception which completely changes the situation. From an evolutionary perspective the stereotypical bad boy who’s sleeping around constantly might not have even as many children as the cautious, financially stable guy who is monogamous because the former guy’s partners are looking for fun while the latter’s is intentionally trying to start a family.

> remember that we are not descended from fearful men

Edward R. Murrow

Cultural influences matter a lot too. Even if the parents past down certain genes, a lot of that can be suppressed by environmental or cultural factors, everything from lifestyle to propaganda.

It's different when you're randomly drafting conscripts from the overall population though, vs having "brave" genes self-select into mortal combat before they can reproduce.