On evolution, how we talk about it incorrectly, and when humans will speciate
Many people today think of evolution and natural selection entirely incorrectly.
We often repeat the idea that individuals compete to pass on their genes and through this process, coupled with advantageous mutations passed down to their offspring, those individuals or their offspring “evolve”.
It’s painted as “survival of the fittest”, whereby only the healthiest and strongest individuals get to pass on their genes and either become or create “evolved beings” – a fallacious view of Darwinian evolution that is at the foundation of “Social Darwinism”.
The problem is that this isn’t at all what happens.
Evolution doesn’t care about individuals.
Two major driving factors of evolution are genetic drift and gene flow – the former occurs when populations become isolated from each other, allowing them to diversify and speciate; the latter occurs when species populations interact, preventing speciation as the population breeds indiscriminately, which dilutes the gene pool instead of forcing it to diverge for the original population.
Genetic drift typically takes a long time to result in speciation, and gene flow can very quickly halt any progress towards speciation even after prolonged periods of isolation between populations.
Hence why genetic drift in human populations largely isolated from each other for millennia didn’t result in speciation, in the main due to the relative small timescales of the isolation and the effects of gene flow whenever that isolation was eventually broken or punctuated.
Evolution doesn’t happen to individuals, and not just in terms of a person evolving during their lifetime. *Populations* evolve, not individuals or their immediate offspring.
Evolution is about the changes in allele frequencies in a population over time. It has nothing to do with individuals beyond a most minor level.
Speciation doesn’t occur because of one or two mutations getting passed on to a family’s offspring.
It takes *many* mutations from *many* different groups in a population, which in turn must be isolated from the larger population or other population groups.
As such, it isn’t actually about individual competition, and it has nothing to do with the survival of the fittest.
Whether you survive to pass on your genes or die before you get the chance, has practically zero bearing on the process of evolution, because your children will not magically be a new species – your genetic mutations don’t magically code for “new species of human”.
Speciation is a cumulative and emergent effect, not a sudden over-night phenomenon.
Whilst your genetic mutations can play a part in that cumulative and emergent process, it will happen with or without you and your role in it is as close to negligible as to be practically irrelevant.
Again: evolution happens to *populations*, not individuals or their immediate offspring.
It isn’t your genes that will magically create a new and/or better species of human, or in any way create a “more evolved” human.
To put it clearer, even in isolated populations, the genetic mutations you pass on may very likely be overridden or diluted by others. So the genetic mutations of you and your partner have statistically little affect on speciation.
Individuals don’t matter, it’s the *collective process* that determines speciation.
It should also be noted that evolution is environmentally led, not individually led.
If your species needs a certain amount of oxygen in the atmosphere in order to breathe properly, and the level of atmospheric oxygen drops, it doesn’t matter how fit or strong or intelligent you are – you die out.
And you personally can’t make the many genetic mutations occur for you and your offspring to evolve the body plan capable of surviving with lower levels of atmospheric oxygen. Unless you are lucky enough to play a part in a long and fortunate process of cumulative mutations that result in such body plans evolving over a necessary long time period, you die out.
Game over, thanks for playing.
And this gets to another piece of annoyingly incorrect terminology often used in relation to evolution – the “evolutionary arms race”.
This term typically describes the process by which both prey and predator adapt over time to either avoid getting eaten or become better hunters.
The problem is that it implies some kind of intent or agency that doesn’t exist.
In an arms race, both sides actively engage in research and development projects, intentionally designing new weapons to defeat the enemy.
There is no intention in evolution. It’s a blind process in which population groups gain an advantage due to environmental factors completely outside of their control and without any individual or collective agency guiding that process.
It’s not an arms race. Neither side is purposefully trying to “out-evolve” the other. Environmental factors and changes in allele frequencies in population groups lead to new species emerging with different characteristics, which in turn define the dynamics of the food chain and the success and potential of the different species involved.
It doesn’t sound as sexy as an “arms race”, but it’s a hell of a lot more accurate and doesn’t readily lend itself to “Social Darwinism” on either an individual or global scale.
Gene flow is also the reason why human beings won’t speciate until we colonise new star systems, when those populations will be necessarily isolated enough from each other for genetic drift to take hold.
Whilst we’re only colonising our own solar system, movement of people between the colonies will be too simple and frequent for speciation to occur, as gene flow dominates over genetic drift.
It is only when we create colonies vastly isolated from each other, where movement between colonies is extremely rare and difficult – such as between star systems – that genetic drift will take over, and speciation will become an inevitability.