Ontogeny and Phylogeny

Blurb

Ontogeny and Phylogeny is Stephen Jay Gould's first technical book, published in 1977 by Belknap, a division of Harvard University Press. Gould wrote that Ernst Mayr suggested in passing that he write the book, but that "I only began it as a practice run to learn the style of lengthy exposition before embarking on my magnum opus about macroevolution." This became The Structure of Evolutionary Theory, published in 2002.
Ontogeny and Phylogeny explores the relationship between embryonic development and biological evolution. The book also discusses the role recapitulation—Ernst Haeckel's discredited idea that embryonic developmental stages replay the evolutionary transitions of adult forms of an organism's past descendants—had on biology, theology, and psychology. The second half of the book details how modern concepts such as heterochrony and neoteny have in influencing macroevolution.
It has been said that of all the books that Gould wrote in his career, "the one with the most impact is probably Ontogeny and Phylogeny ... to say that this work is a hallmark in this area of evolutionary theory would be an understatement.