Many may not know but Haekel's work were adopted by Nazism following his racist views. Haekel said that the Germans were members of a biologically superior community (akin to Nietzsche's 'super-man'). More about Haekel here.
New Scientist reviewed a book by Bob Hopwood, a science historian, who had his book recently published. The full review can be found here and reproduced in part below.
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Some of the most iconic images in biology hold a dark secret. Haeckel's Embryos: Images, evolution, and fraud delves into their history
IT's embarrassing but true: some of the most influential drawings in the history of biology are wrong, exaggerated to fit a thesis.