Scaling of swim speed and stroke frequency in geometrically similar penguins: they swim optimally to minimize cost of transport
- 11 November 2009
- journal article
- Published by The Royal Society in Proceedings Of The Royal Society B-Biological Sciences
- Vol. 277 (1682), 707-714
- https://doi.org/10.1098/rspb.2009.1515
Abstract
It has been predicted that geometrically similar animals would swim at the same speed with stroke frequency scaling with mass−1/3. In the present study, morphological and behavioural data obtained from free-ranging penguins (seven species) were compared. Morphological measurements support the geometrical similarity. However, cruising speeds of 1.8–2.3 m s−1 were significantly related to mass0.08 and stroke frequencies were proportional to mass−0.29. These scaling relationships do not agree with the previous predictions for geometrically similar animals. We propose a theoretical model, considering metabolic cost, work against mechanical forces (drag and buoyancy), pitch angle and dive depth. This new model predicts that: (i) the optimal swim speed, which minimizes the energy cost of transport, is proportional to (basal metabolic rate/drag)1/3 independent of buoyancy, pitch angle and dive depth; (ii) the optimal speed is related to mass0.05; and (iii) stroke frequency is proportional to mass−0.28. The observed scaling relationships of penguins support these predictions, which suggest that breath-hold divers swam optimally to minimize the cost of transport, including mechanical and metabolic energy during dive.Keywords
This publication has 29 references indexed in Scilit:
- Phenotypic plasticity in the scaling of avian basal metabolic rateProceedings Of The Royal Society B-Biological Sciences, 2006
- Emperor penguins adjust swim speed according to the above-water height of ice holes through which they exitJournal of Experimental Biology, 2005
- Synchronous diving behavior of Adélie penguinsJournal of Ethology, 2004
- Swim speed of free-ranging Adélie penguinsPygoscelis adeliaeand its relation to the maximum depth of divesJournal of Avian Biology, 2002
- Energetics of Free-Ranging SeabirdsPublished by Taylor & Francis Ltd ,2001
- Benthic diving in male emperor penguins Aptenodytes forsteri foraging in winterMarine Ecology Progress Series, 2000
- Life in Moving FluidsPhysics Today, 1995
- Animal Physiology: Adaptation and Environment.Journal of Applied Ecology, 1985
- Phylogenies and the Comparative MethodThe American Naturalist, 1985
- Kinematics of swimming of penguins at the Detroit ZooJournal of Zoology, 1979