Controversial but standard. Haeckel’s enemies continued to exploit the forgery charges. Controversy exploded in the early 1900s, when organized atheists clashed with anti-Darwinists promoting Christian approaches to science. Biologists did not condone Haeckel’s schematizations, but hardly any doubted (from the abundance of other evidence) that evolution had occurred and a majority defended him against criticism from outside. Remarkably, in spite of specialist and antievolutionist criticism, American textbooks reprinted Haeckel’s grids through the twentieth century, as the standard illustration of the embryological evidence of evolution. So some of the most controversial pictures of embryos are also among the most widely seen. In the late 1990s, revived interest in evolution and development combined with the rise of creationism and concern over fraud in science to make his pictures intensely controversial again.

Forgery charges

Some university teachers of embryology welcomed Haeckel’s pictures, but experts who disagreed with his particular approach to Darwinism accused him of making embryos look more similar than they really are.

Haeckel was criticized fast, but the attacks took several years to take off. The Basel zoologist Ludwig Rütimeyer raised the alarm. First, he charged Haeckel with having figures representing different species printed from the same block . Obviously sharp practice, Haeckel corrected this in the second edition and eventually explained it away as ‘extremely rash foolishness’. Second, Rütimeyer said Haeckel had tendentiously miscopied standard illustrations. This was much more debatable. Even as the Natural History of Creation made Haeckel a lightning rod for Darwinist controversy, these figures had enough competent supporters to stay through many editions.

Haeckel’s second semi-popular book, the Anthropogeny (1874), was filled with new and provocative pictures, including a much expanded comparative embryological grid. Rütimeyer’s ex-colleague, Wilhelm His, who had developed a rival, physiological embryology, which looked, not to the evolutionary past, but to bending and folding forces in the present. He now repeated and amplified the charges, and lay enemies used them to discredit the most prominent Darwinist. But Haeckel argued that his figures were schematics, not intended to be exact. They stayed in his books and were widely copied, but still attract controversy today.

Haeckel’s expanded embryological comparison, 1874


Illustrations by Wilhelm His to show ‘the specific physiognomies of young embryos’, 1874