How Many Have Read Darwin? 

Of course no-one has any idea of how many people actually read any book! But I am one who did read Darwin’s 1859 book On the Origin of Species, and who (as a result of that reading) became a fan of his beautifully clear and convincing writing and of the insight he shared with Wallace and others that the entire variety of living organisms might be just the result of a process of natural selection acting on the results of some (as then unknown) source of random variation between parents and offspring. That the words “might be” can almost certainly be replaced by “is” depends of course on subsequent discoveries about the process of inheritance and the mechanisms and rate of “mutations” that lead to the assumed random variation, as well as on the fact that the age of the Earth is actually much greater than was understood at the time of his writing. But the fact that everything we have discovered since then (from the existence of nuclear fusion to keep the sun and earth warm for long enough, to the details of how the rate at which DNA encoding of protein structures can get altered by radiation and other factors) all support his idea… Well that just increases my admiration for the power of his insight!

Source: (1002) Alan Cooper’s answer to How many Charles Darwin fans actually read his theory of evolution? – Quora