Someone asked this question on Reddit. They point out that human lifestyles change “incredibly fast” compared to evolution, which in turn “might not have enough time to catch up.” They want to know:

So how does human evolution work in a world where the environment and ways of life are constantly shifting? Are we still undergoing biological evolution, or has culture and technology replaced the need for it?

Below is my lightly edited answer.

There are three different types of evolution we know of.

1. Biological evolution: the replication, variation, and selection of genes.
2. Cultural evolution: the replication, variation, and selection of memes (Dawkins).
3. Mental evolution: the replication, variation, and selection of ideas within a single mind.

In all three cases, evolution explains the origin of knowledge.

All life undergoes biological evolution. Only some animals have memes (eg apes and cats). Humans are the only ‘animal’ that has mental evolution on top of that (which makes them so markedly different from all other life that it’s actually misleading and inappropriate to call them ‘animals’).

Humans still undergo biological evolution and will continue to do so for as long as we remain in our biological bodies. Maybe one day we can transfer our minds to machines, but until then, our genes will continue to evolve.

Human memes replicate differently from animal memes. In his book The Beginning of Infinity, physicist David Deutsch explains (chapter 16) that animals replicate memes by mindless imitation only, which means the reach of animal memes is inherently limited. Humans, on the other hand, replicate memes by understanding and then enacting their purpose. So although some animals have a ‘culture’ of sorts, it’s fundamentally limited compared to human culture and will drive animal evolution only to an extent. Human culture (language, spacecraft, medicine, poems, movies, etc) has a much greater effect on human evolution generally. Animal memes evolve faster than genes, but human memes evolve faster still, because humans replicate memes faster. Since gene evolution is so slow in comparison, memes have a far greater impact on our lives.

Mental evolution is my own, original contribution building on previous work by philosopher Karl Popper. He suggested that knowledge grows through an evolutionary process of guesses and criticism, where guesses of new ideas are like mutations in genes and criticisms are like selection. That’s not an analogy, as Popper points out: ideas literally grow through an evolutionary process. It’s not biological evolution, to be sure, but still evolution. (Abstractly speaking, evolution is something any pool of imperfect replicators undergoes.) However, Popper did not consider the central role of replication as the driving force of mental evolution. In my neo-Darwinian approach to the mind, I explain the origin of human creativity by drawing an analogy to the abiogenesis of life and the RNA World hypothesis on the one hand and the historic occurrence of the first self-replicating idea inside a single mind. In addition, this approach provides a new way to explain phenomena such as memory.

Human creativity also explains why we have so much junk DNA, and why we have fewer genes than even simple organisms such as flies.

It’s hard to overstate how much evolution of ideas happens inside a single mind. Think of all of the ideas a person comes up with in his lifetime. Many of those he never even becomes consciously aware of, yet they can still have an impact. His genes, on the other hand, remain the same throughout his lifetime. This is one of the reasons evolutionary psychology is overrated: genes simply can’t have as much of an impact on humans as ideas. (Another issue with evo psych is that, again, it’s inappropriate to study humans as if they were animals.)

So yes, humans still undergo biological evolution, and it does have some impact on their evolution in the wider sense, but not nearly as much as many people think. Memes have a greater impact on human evolution, and every person’s individual creativity has by far the greatest impact on his own evolution while his genes remain the same throughout his life. If someone has a genetic mutation that causes cancer for which there is currently no cure, then whether he lives ultimately depends on human creativity and creating the knowledge for how to cure it. If he instead waited for his genes to find a cure, he’d be sure to die.

These are the three different sources of knowledge in every person’s life: genes (limited, just a starting point); memes (far greater impact than genes); an individual’s creativity, ie the mental evolution occurring inside a single mind. The last one typically is by far the most important. Without it, human meme replication wouldn’t even be possible in the first place. However, just how creative any one person ends up being depends, among other things, on his courage, his honesty, his rationality, his desire for progress, and the kind of society he lives in (see The Beginning of Infinity chapter 15).