Haeckel's manipulation of evidence was recognized in his own time. He was attacked for fraud by both embryologists and creationists, with whom he battled incessantly. Still, many of his drawings can be found in textbooks well into the 20^th century. Stephen Jay Gould lamented this ongoing inaccuracy in his 1977 book Ontogeny and Phylogeny. The controversy was rekindled in the late 1990s when British embryologist Michael K. Richardson published Haeckel's drawings alongside contemporary photographs (shown at right) that demonstrate Haeckel's errors.

Much to his dismay, Richardson's critique was seized on by creationists, who plastered his work on their Web sites. Of course, the case for evolution does not hang on Haeckel's drawings, as is clear from a mountain of other evidence.