Comparative morphometrics of cetaceans

The proportions of giants

Why does the humpback whale have flippers a third of its body long? Why does the sperm whale have an asymmetrical skull? This database presents the characteristic morphometric ratios of the main species.

Going further

Morphology shapes swimming: hydrodynamics, swimming performance, anatomical counts and scale comparator.

Morphometrics: what do the proportions say?

Morphometrics compares body length, the length of the flippers and tail flukes, dorsal fin height and blubber thickness. These proportions reveal ways of life. The outsized flippers (~5 m, a third of the body) of the humpback whale (Megaptera = “great wing”) optimise the tight manoeuvrability of bubble net feeding.

The tall, straight dorsal fin of the male killer whale (up to 1.8 m) works as a sexual signal; the bowhead whale has none at all, which eases its passage under the sea ice. The broad horizontal flukes (tail) of rorquals exploit the optimal Strouhal regime for long migrations. The head makes up a third of the body in the sperm whale and houses the largest acoustic organ in the animal kingdom: the spermaceti organ.