Book Review: Greenspan, Stanley I. & Shanker, Stuart G. (2004). The First Idea: How Symbols, Language, and Intelligence Evolved from Our Early Primate Ancestors to Modern Humans. Cambridge, MA: De Capo Press. 504 pp., $25.00 (hardback)

YOU MAY REMEMBER THE FIGURE FROM YOUR HIGH SCHOOL biology textbook: in drawn parallel images it showed the embryonic development of fish, amphibians, reptiles, pigs, and humans and was titled, “ontogeny recapitulates phylogeny.” That now famous phrase was coined in 1866 by German zoologist and early evolutionary zealot Ernst Haeckel, who also made the drawings. Haeckel claimed that he had discovered that the development of each individual repeated the evolution of its species. He dubbed his discovery the biogenic law, now also known as the theory of recapitulation.

Haeckel's drawings are uncanny in showing how at various stages the human fetus looks like the fetus of a fish, an amphibian, a reptile, and so on. Unfortunately, the drawings are deceptions, tendentiously selected and rendered to overemphasize the similarities and downplay the differences. Within a few years of their publication Haeckel was accused of fraud by his colleagues. While admitting inexactitude, he defended the drawing as providing schematic illustrations of his theory rather than evidence for it. The evidence for the biogenic law was incontrovertible, he claimed; the drawings simply made it easier to understand. As it turns out, the biogenic law—along with the drawings—has been dismissed by scientists for decades. It's a powerful metaphor that inspired some of the very research that disproved it; in fact there are links between evolution and biological maturation, but they are far more complex than anyone in Haeckel's time could have imagined. Yet “ontogeny recapitulates phylogeny” and Haeckel's drawings found their way into textbooks until the last decade of the 20th century. Powerful metaphors supported by simple illustrations die hard.

British philosopher Herbert Spencer, a contemporary of Haeckel, wrote made similar claims about mental development:

“If there be an order in which the human race has mastered its various kinds of knowledge, there will arise in every child an ap