"Marx wanted to dedicate his Das Kapital to Charles Darwin."
FYI, this actually is NOT true.
For anyone reading, Marx did write to Darwin at some point and sent him a copy of Das Kapital Vol I (though Darwin never read it.)
Anyway where this myth comes from is that there was a letter from Darwin saying about the dedication of a "volume" (which has been interpreted as Vol II of Das Kapital) to him and how he did not want it dedicated to him. However, this letter was not written to Marx, but someone else.
See "Marx and Darwin: A Reconsideration" by Terence Ball, Political Theory (1979)