title: Transitions during cephalopod life history: the role of habitat, environment, functional morphology and behaviour.
abstract: Cephalopod life cycles generally share a set of stages that take place in different habitats and are adapted to specific, though variable, environmental conditions. Throughout the lifespan, individuals undertake a series of brief transitions from one stage to the next. Four transitions were identified: fertilisation of eggs to their release from the female (1), from eggs to paralarvae (2), from paralarvae to subadults (3) and from subadults to adults (4). An analysis of each transition identified that the changes can be radical (i.e. involving a range of morphological, physiological and behavioural phenomena and shifts in habitats) and critical (i.e. depending on environmental conditions essential for cohort survival). This analysis underlines that transitions from eggs to paralarvae (2) and from paralarvae to subadults (3) present major risk of mortality, while changes in the other transitions can have evolutionary significance. This synthesis suggests that more accurate evaluation of the sensitivity of cephalopod populations to environmental variation could be achieved by taking into account the ontogeny of the organisms. The comparison of most described species advocates for studies linking development and ecology in this particular group.
authors.affiliation: Université de Caen Basse-Normandie, UMR BOREA: Biologie des ORganismes et des Ecosystèmes Aquatiques, Esplanade de la paix, CS 14032, 14032 Caen, France; UMR BOREA, UMR CNRS7208, IRD207, UPMC, MNHN, UCBN, 14032 Caen, France. Electronic address: jean-paul.robin@unicaen.fr.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Robin
authors.affiliation: Rhodes University, Grahamstown, South Africa; Oceans & Coasts Research, Victoria & Alfred Waterfront, Cape Town, South Africa.
authors.forename: Michael
authors.initials: M
authors.lastname: Roberts
authors.affiliation: Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California, USA.
authors.forename: Lou
authors.initials: L
authors.lastname: Zeidberg
authors.affiliation: School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, United Kingdom.
authors.forename: Isobel
authors.initials: I
authors.lastname: Bloor
authors.affiliation: El Colegio de la Frontera Sur, Colonia Casasano, Cuautla, Morelos, Mexico.
authors.forename: Almendra
authors.initials: A
authors.lastname: Rodriguez
authors.affiliation: Institute for Marine and Antarctic Studies (IMAS), University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Felipe
authors.initials: F
authors.lastname: Briceño
authors.affiliation: Department of Ichthyology and Fisheries Science, Rhodes University, Grahamstown, South Africa; Bayworld Centre for Research & Education, Constantia, Cape Town, South Africa.
authors.forename: Nicola
authors.initials: N
authors.lastname: Downey
authors.affiliation: Unidad Multidisciplinaria de Docencia e Investigación, Universidad Nacional Autónoma de México, Puerto de Abrigo s/n, Sisal, Yucatán, México.
authors.forename: Maite
authors.initials: M
authors.lastname: Mascaró
authors.affiliation: Integrative Oceanography Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California, USA; Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California, USA.
authors.forename: Mike
authors.initials: M
authors.lastname: Navarro
authors.affiliation: Instituto de Investigaciones Marinas (CSIC), Vigo, Spain.
authors.forename: Angel
authors.initials: A
authors.lastname: Guerra
authors.affiliation: Caldwell Laboratory, Department of Integrative Biology, University of California, Berkeley, California, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Hofmeister
authors.affiliation: Laboratório de Ecossistemas Pesqueiros (LabPesq), Universidade de São Paulo, Instituto Oceanográfico Praça do Oceanográfico, Butantã, São Paulo, SP, Brazil.
authors.forename: Diogo D
authors.initials: DD
authors.lastname: Barcellos
authors.affiliation: IPMA Div. RP, Departamento do Mar e Recursos marinhos, Lisboa, Portugal.
authors.forename: Silvia A P
authors.initials: SA
authors.lastname: Lourenço
authors.affiliation: Smithsonian Institution, National Museum of Natural History, Washington, District of Columbia, USA.
authors.forename: Clyde F E
authors.initials: CF
authors.lastname: Roper
authors.affiliation: School of Environmental & Life Sciences, University of Newcastle, Ourimbah, New South Wales, Australia.
authors.forename: Natalie A
authors.initials: NA
authors.lastname: Moltschaniwskyj
authors.affiliation: Department of Environment and Primary Industries, Fisheries Victoria, Queenscliff, Victoria, Australia.
authors.forename: Corey P
authors.initials: CP
authors.lastname: Green
authors.affiliation: Psychology Department, University of Lethbridge, Lethbridge, Alberta, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Mather
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D049830:Cephalopoda / Q000254:growth & development* / Q000502:physiology*; D017753:Ecosystem; D008018:Life Cycle Stages
keywords: Acquisition of behaviours; Adult; Cephalopod ontogeny; Cohort survival; Environmental variability; Habitat shifts; Juvenile; Life stages; Morphological changes; Paralarvae; Subadult