Haeckel’s Embryos

Setting the Record Straight Original Article

In The Origin of Species Charles Darwin wrote that “the embryos of mammals, birds, fishes, and reptiles [are] closely similar, but become, when fully developed, widely dissimilar.” He inferred that all vertebrates “are the modified descendants of some ancient progenitor,” and that “the embryonic or larval stages show us, more or less completely, the condition of the progenitor of the whole group in its adult state” (Darwin 1859, pp. 338, 345). Darwin’s contemporary Ernst Haeckel called this the “Biogenetic Law,” according to which “ontogeny recapitulates phylogeny.” To illustrate the law, Haeckel (1891) produced drawings of vertebrate embryos which have been widely used in biology textbooks ever since (Figure 1).

Continue Reading the PDF Version

Jonathan Wells

Senior Fellow, Center for Science and Culture
Jonathan Wells has received two Ph.D.s, one in Molecular and Cell Biology from the University of California at Berkeley, and one in Religious Studies from Yale University. A Senior Fellow at Discovery Institute's Center for Science and Culture, he has previously worked as a postdoctoral research biologist at the University of California at Berkeley and the supervisor of a medical laboratory in Fairfield, California. He also taught biology at California State University in Hayward and continues to lecture on the subject.