Genetic Evolution Was a Prelude to Memetic Evolution
In fact, I've got behind me Popper's book called Objective Knowledge and it's subtitled An Evolutionary Approach and that's no accident at all either. There's symmetry between the theory of epistemology and the theory of evolution as we understand it.
Before we understood what is known as the Darwinian theory of evolution, the only idea that people had was these entities had to be created. All the plants and animals that you see around you had to be created by a Creator; there was no explanatory mechanism. Some people came up with the idea of gradual change over time. Lamarck was one such idea; the reason why giraffes have long necks is because their ancestors had slightly shorter necks, so they tried to stretch their necks to reach the leaves that they couldn't reach.
But again, there was no mechanism for this beyond the fact that an individual goes off to the gymnasium and works on their biceps and their biceps get a little bigger over time. Although you can work out in the gym and increase the size of your biceps, that doesn't mean your children are going to inherit those characteristics.
So what Darwin came up with is a similar idea to what Popper had in knowledge; it was error correction. The idea that an organism would trial itself out in a particular environment and if it wasn't, as we say, fit for that environment, then it would die off. But if it was fit in that environment, then it would survive.
So you have this encounter with reality between living organisms and the environment, and it's the environment that's giving you feedback from reality and destroying those organisms that aren't fit enough to survive. The Neo-Darwinist view is to give us what the unit of selection is; it's not the group or the herd, it's not even the individual; it's the gene.
It's the selfish gene idea which comes to us from Richard Dawkins, who says if any one of those genes happens to be not fit for the particular environment, that could cause the death of that organism. But the species might not go extinct; the species might survive, but its entire DNA will ever so subtly change over time as the environment changes.
And now we have leveled that up; we human beings are the next step in that evolutionary process where we can create explanatory knowledge which does the same thing. Deutsch likes to say genetic evolution was merely a prelude; what's coming next is mimetic evolution. The history of the universe from here on out is going to be the history of ideas undergoing the same evolutionary process as what the genes did previously.