How long would it take to become a giant squid?
Laboratory and field studies suggest that cephalopod growth occurs rapidly and is linked to temperature throughout a short life span. For giant squid such as Architeuthis, a paucity of size-at-age data means that growth is only inferred from isolated field specimens, based on either statoliths or isotopic analyses of tissue. In this study we apply simple growth models to obtain projections of the life span required to achieve the Architeuthis average body mass in scenarios which include an energy balance between rates of food intake and expenditure on growth and metabolism. Although the analysis shows that a wide range for the estimated life span is possible, energy conservation suggests that achievement of a larger size would be assisted by slower exponential growth early on. The results are compared with a sparse set of size-at-age data obtained from male and female Architeuthis wild specimens and possibly hint at some behavioural differences between males and females.
KeywordsFeeding and metabolic rates Simple two phase growth model Energy balance Architeuthis Giant squid Cephalopod growth Growth models
We especially thank Sophie des Clers and Natalie Moltschaniwskyj for several comments which greatly improved the original manuscript of this paper.
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