Maybe the error in this thread is to assume the first genius to come up with a given theory then becomes to ultimate be all end all of that particular branch of science.
We could talk about a another certified genius by the name of Newton, who first really accurately described and pioneered the the understanding of the laws of Physics while inventing some new mathematics to better describe those laws. And to this day, many of the laws of Physics bear the name Newtonian physics. And only in the last century or so have new people come along in the field of relativity and quantum mechanics to extend those laws to the realm of the minute and to cosmic scales.
Yet when Newton was asked at the time, how he could see so much further than his many others who had far more flawed Physics models , Newton was quick to say he stood on the shoulders of other giants.
And now for an understanding of evolution we stand on the shoulders of giants like Darwin and Mendel. After all why should we leave out Mendel? Darwin merely proposed a mechanism of natural selection should exists, it was Mendel who described the math of how it worked.