Open AccessLarval transfer and the origins of larvae
Author(s) -
WILLIAMSON DONALD I.
Publication year - 2001
Publication title -
zoological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.148
H-Index - 83
eISSN - 1096-3642
pISSN - 0024-4082
DOI - 10.1111/j.1096-3642.2001.tb01310.x
Subject(s) - biology , deuterostome , larva , lineage (genetic) , metamorphosis , zoology , evolutionary biology , phylogenetics , hybrid , genome , ecology , gene , genetics , botany
Larval transfer is presented as an alternative to the widely held assumption that larvae and corresponding adults have always evolved together, within the same lineage. I submit (1) that genes specifying the basic forms of all embryos and larvae originated as the genomes of animals that matured without metamorphosis, (2) that such genomes have been transferred by hybridization, and (3) that fertile hybrids have been produced at infrequent and irregular intervals between animals at all levels of relationship during the course of evolution. The origins of blastulas, hydromedusae, protostome and deuterostome ciliated larvae, arthropodan larvae and urochordate tadpoles are discussed as examples of my hypothesis. I believe that practically all metazoans have at least one inter‐group hybrid in their ancestry. Larval transfer is briefly considered in relation to other theories on ontogeny and phylogeny. Methods of verification are suggested.