Haeckel s illustrations show vertebrate embryos at different stages of development, which exhibit embryonic resemblance as support for evolution, recapitulation as evidence of the Biogenetic Law, and phenotypic divergence as evidence of von Baer s laws.
12.
The first half of the book explores Ernst Haeckel's biogenetic law ( recapitulation ) the largely discredited idea that embryonic developmental stages replay the evolutionary transitions of adult forms of an organism's past descendants and how this idea influenced thinking in biology, theology, and psychology.
