Remaining relatively unchanged for over 550 million years, jellyfish are among the simplest multi-organ lifeforms, yet much of their life history remains poorly understood. Some of the remarkable abilities of these organisms challenge the predictions of many ecological and physiological models. I am undertaking a Natural Environment Research Council (NERC) funded PhD project, supervised by Prof. Andrew Hirst, Prof. David Atkinson, Dr Mathew Spencer (all of University of Liverpool), and Dr Cathy Lucas (University of Southampton), to analyse how metabolic rates and body size are related in jellyfish, with particular reference to how body surface area for exchange of materials change over their development.
Many gelatinous species (including ctenophores, cnidarians and thaliaceans) demonstrate isometric or even hyperallometric scaling of metabolic rates over ontogeny (i.e. they have constant mass-specific metabolic rates, or even mass-specific rate that increase as an animal enlarges). Such relationships are prime illustrations of the “rule bending” seen in many pelagic invertebrates, which contrast with the physiological and ecological rates achieved by many other organisms. This project will provide novel insights into what drives metabolic demand as animals enlarge, but also how oxygen and substrates can be supplied to every mitochondrion in the body. This work has implications to a wide range of animals, beyond the model of jellyfish.