title: Postscript: some concluding observations and speculations.
authors.affiliation: School of Biological Sciences, University of Exeter, Exeter, EX4 4QG, UK.
authors.forename: S G
authors.initials: SG
authors.lastname: Hughes
authors.forename: J M
authors.initials: JM
authors.lastname: Garland
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D004261:DNA Replication; D006801:Humans; D008018:Life Cycle Stages; D063245:Plant Development; D018515:Plant Leaves / Q000254:growth & development; D018547:Plant Stems / Q000254:growth & development