Charles Darwin's educational and scientific attainments were not exactly of the highest, particularly when compared to all the opportunities available in our own day. Darwin embarked on medical studies in Edinburgh, but failed to complete them and abandoned the course half-way through. For that reason, when he launched the theory of evolution, he was ignorant of many branches of science closely related to his theory.
Thomas Huxley was Darwin's closest friend and greatest supporter in terms of the theory of evolution. He is even remembered as "Darwin's bulldog" for his vociferous defense of the theory of evolution on Darwin's behalf. But even he admitted of this friend:
Like the rest of us, he had no proper training in biological science.23
From a letter written to Darwin by A. Sedgwick, his closest friend:
23- Francis Darwin, The Life and Letters of Charles Darwin, Vol. I, p. 315.Parts of it I admired greatly, parts I laughed at till my sides were almost sore; other parts I read with absolute sorrow, because I think them utterly false and grievously mischievous... Many of your wide conclusions are based upon assumptions...24
24- Francis Darwin, The Life and Letters of Charles Darwin, Vol. II, p. 43.