Transitions during cephalopod life history: the role of habitat, environment, functional morphology and behaviour
Robin, J-P and Roberts, M and Zeidberg, L and Bloor, I and Rodriguez, A and Briceno, F and Downey, N and Mascaro, M and Navarro, M and Guerra, A and Hofmeister, J and Barcellos, DD and Lourenco, SAP and Roper, CFE and Moltschaniwskyj, NA and Green, CP and Mather, J, Transitions during cephalopod life history: the role of habitat, environment, functional morphology and behaviour, Advances in Marine Biology, 67 pp. 361-437. ISSN 0065-2881 (2014) [Refereed Article]
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.
cephalopod ontogeny, life stages, morphological changes, acquisition of behaviours, habitat shifts, environmental variability, cohort survival, paralarvae