It is widely accepted that we humans evolved via accumulating genetic mutation for the majority of our evolutionary history. Only until very recently after we learn to acquire knowledge, initially through customs and rituals and later through codification (in recorded forms) that we start to evolve via means other than genetic mutation. With the acquisition of knowledge and subsequent manipulation of knowledge to generate a particularly consequential type of knowledge, namely “ideas” human begins to interact with the environment in ways that is different to how their gene have drive them. That was a mouthful, let me unpack it.
Our genes not only determines our anatomy, it also affect our behavior towards our environment. For example when a humans stand on the edge of a cliff, that human will instinctively incline to walk back and for most cases males instinctively prefer to cosy up with a female than another male.
With ideas, humans can develop new ways to interact with the environment. These kind of interaction range from making sophisticated stone tools to building a supercomputer.
Now let me go back and explain why i refer to human knowledge development as a form of evolutionary process. This is because human knowledge development (“adaptation” is probably a more accurate word instead of “development”) is driven by the same evolutionary process as genes, namely heritability, variation and selection. In the case of knowledge, scientist use the word meme to describe the knowledge equivalent of gene. Driven by humans interaction with memes, memes are copied from carriers of memes such as people, customs, rituals, books and other media to other carriers. Variation occurs when memes is not accurately pass on from carrier to carrier or when new memes interact with other existing meme in a human carriers mind (creating new idea or knowledge). Through selection pressure, memes that is either difficult to co-exist with other memes, difficult to be copied or unattractive will eventually decrease in population and make room for other memes. It is through this process memes spread and evolve. As memes evolve, humans gain the benefits of increasingly sophisticated memes that give us incredible power to manipulate our environment. Going to the moon for example.
In morden times, memes rather than genes accounts for almost all of our adaptive capacity. Furthermore due to the nature of our economy (we really value innovation) and information technology the proportion of our adaptation by memes is growing even more. This does not mean that we are no longer evolving genetically, we still are (eg: here and here), in fact genes and memes coevolve, its just that memes evolve faster and have larger impact. There can also be other form of human adaption, like accumulation of change we have done to the environment. I decide not to dwell to much on it, because it is largely a manifestation of our memes.
I hope that answers your questions, and its not too dry.