Animals start their life as single cells, resembling simple living beings, to become the most complex objects of the known universe. The development of species with completely different adult body plans (like a barnacle and a lobster, or a squid and a snail) uncovers deep phylogenetic relationships. That's why embryology, developmental biology, and evo‐devo have been and are so important for evolutionary biology: ontogenies help to understand phylogenies. The name of a species, thus, should evoke not only the adult stage: Thunnus thynnus, the blue fin tuna, is an egg, a larva, a juvenile, and a series of growth stages. Its predators range from tiny jellyfish eating its eggs and larvae, to white sharks, to us. Its prey ranges from tiny crustaceans to large fish. Constraints on the size of adult populations often act on early ontogenetic stages. The reconstruction of ontogenies, and the understanding of the rules determining for them, thus, is a prerequisite to perform both evolutionary and ecological studies. The genes involved in the making of a phenotype do not act all at the same time. The genotype is identical in polyps and in their medusae, in caterpillars and in their butterflies: the same genotype can make so different phenotypes, and both natural and sexual selection act on their ecological and reproductive performances.
The conservation of species should regard their whole life history (Espinosa et al. Citation2008), just as their description should regard their whole life cycle (Gravili et al. Citation2007; Lanfranchi & Melai Citation2008). The Italian Journal of Zoology calls all zoologists to consider their favourite organisms as multidimensional objects, both in the space they occupy and in the time they live. Pieces of knowledge just like the decriptions of larvae (Ferretti et al. Citation2007; Zetto Brandmayr Citation2007), the morphogeny of their structures (Avallone et al. Citation2007) and their physiological and ecological performances (Zega et al. Citation2007) reveal the multifaceted phases in the life of organisms, phases that need to be reconciled with each other, by bridging gaps across sub‐disciplines.
References
- Avallone , B. , Fascio , U. , Balsamo , G. , Bianco , P. G. , Balassone , G. and Marmo , F. 2007 . Morphogenesis of otoliths during larval development in brook lamprey, Lampetra planeri. . Italian Journal of Zoology , 74 : 247 – 258 .
- Espinosa , F. , Gonzalez , A. R. , Maestre , M. J. , Fa , D. , Guerra‐Garcia , J. M. and Garcia‐Gomez , J. C. 2008 . Responses of the endangered limpet Patella ferruginea to reintroduction under different environmental conditions: survival, growth rates and life‐history. . Italian Journal of Zoology , 75 : 371 – 384 .
- Ferretti , C. , Magnino , G. and Balduzzi , A. 2007 . Morphology of the larva and ancestrula of Myriapora truncata (Bryozoa, Cheilostomatida). . Italian Journal of Zoology , 74 : 341 – 350 .
- Gravili , C. , Bouillon , J. , D'elia , A. and Boero , F. 2007 . The life cycle of Gastroblasta raffaelei (Cnidaria, Hydrozoa, Leptomedusae, Campanulariidae) and a review of the genus Gastroblasta. . Italian Journal of Zoology , 74 : 395 – 403 .
- Lanfranchi , A. and Melai , M. 2008 . Parotoplana rosignana sp nov.: Morphology, taxonomy and post‐embryonal development of a new species of otoplanid (Plathelminthes, Rhabdithophora, Proseriata). . Italian Journal of Zoology , 75 : 197 – 206 .
- Zega , G. , Pennati , R. , Dahlstrom , M. , Berntsson , Sotgia , C. and De Bernardi , F. 2007 . Settlement of the barnacle Balanus improvisus: The roles of dopamine and serotonin. . Italian Journal of Zoology , 74 : 351 – 361 .
- Zetto Brandmayr , T. , Mazzei , A. , Talarico , F. , Giglio , A. , Bauer , T. and Brandmayr , P. 2007 . The larva of Siagona europaea Dejean, 1826: Morphology and collecting technique for a subterranean blind ‘running ant killer’ (Coleoptera, Carabidae). . Italian Journal of Zoology , 74 : 239 – 245 .