The mean weight in sea water of specimens of the electric ray, Torpedo nobiliana Bonaarte, was only 0·4 % of the weight in air compared with 4·4 % in other bottom-living rays. T. nobiliana was so buoyant because it had large livers (up to 20% by weight) containing a lot (up to 70 %) of oil of low density (0·91 g/cm3) and because some of the body tissues were less dense than in other rays.
No takes yet. Share an insight, caveat, or question.
B. L. Roberts (1969) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: