Synthesized answer
The provided passages do not explicitly list questions that remain unanswered in the book "Ontogeny and Phylogeny." However, the text does mention that "Ontogeny recapitulates phylogeny" was Haeckel's answer to a "vexing question" in 19th-century biology: what is the relationship between individual development and the evolution of species and lineages [1].
The book then documents the history of this idea of recapitulation, tracing it from its origins to its decline in the early 20th century [1]. While the passages indicate that the concept of recapitulation was presented as an answer to a significant biological question, they do not specify any questions that remained unanswered by the end of the book or within the scope of the provided information.
Synthesized from the book passages below. Chat with the book on Feynman for follow-up.
From the book
Title: Ontogeny and Phylogeny by Stephen Jay Gould Description: “Ontogeny recapitulates phylogeny” was Haeckel’s answer to 19th-century biology’s most vexing question: what is the relationship between individual development and the evolution of species and lineages? Gould documents the history of the idea of recapitulation from its first appearance among the pre-Socratics to its fall in the early 20th century. Categories: Science Pages: 522 Snippet: Gould documents the history of the idea of recapitulation from its first appearance among the pre-Socratics to its fall in the early 20th…