A classic problem in evolutionary biology is the origin of larvae - how and why did they occur? Indeed, it has often been suggested that many entirely unique body plans first originated as retained larvae of ancestral organisms. But what of the larvae themselves? What developmental and evolutionary forces shape and constrain them? These questions and others are dealt with by this international team of leading zoologists and developmental biologists. Intended to contribute to a continuing dialectic, this book presents diverse opinions as well as manifold conclusions. Certain to challenge and intrique, The Origin and Evolution of Larval Forms should be a part of the library of every evolutionary and developmental biologist interested in larvae and their significance.

Many biological facts are irreconcilable with the assumption that larvae and adults evolved from the same genetic stock. The author of this book draws attention to these, and presents his alternative hypothesis that larvae have been transferred from one taxon to another. In his previous book (Larvae and Evolution, 1992), the author used larval transfer to explain developmental anomalies in eight animal phyla. In the present book, he claims that the basic forms of all larvae and all embryos have been transferred from foreign taxa. This leads to a new, comprehensive theory on the origin of embryos and larvae, replacing the discredited 'recapitulation' theory of Haeckel (1866). Metamorphosis, previously unexplained, represents a change in taxon during development.

A science writer reflects on his journey into the profession.