Why was charles darwin drawn as a monkey?Watch
My answer, was because his theory went against the idea, that all animals were created by God - so this depicted him as crazy and ridiculous.
Many people are saying that it was because we humans evolved from monkeys/apes, and this may well be correct - but I used a different answer. There is the explicit point "Darwin's theory went against the idea that god created all animals" is in the syllabus, in B1.4 (I think). Look at the following links, it says in both that Darwin was drawn as an ape/monkey, to expose him to ridicule:
I'm not saying that I am right, I am simply providing an alternative answer that has some evidence for it. The idea that all humans evolved from monkeys could be correct, I'm not denying that. But I think that this answer is a likely correct one, due to the fact that it is an explicit point in the syllabus - and the picture was originally made to make Darwin look ridiculous.