Melon (cetacean)

The melon is a mass of adipose tissue found in the foreheads of all toothed whales.

The melon is structurally part of the nasal apparatus and comprises most of the mass tissue between the blowhole and the tip of the snout.

The function of the melon is not completely understood, but scientists believe it is a bioacoustic component, providing a means of focusing sounds used in echolocation and creating a similarity between characteristics of its tissue and the surrounding water so that acoustic energy can flow out of the head and into the environment with the least loss of energy.

It was once hypothesized that the melon had functions in deep diving and buoyancy, but these ideas are no longer considered valid by cetologists.

The bulk of that nose is composed of two large, fatty structures, the spermaceti organ and the "junk".

Typically, the inner core of the melon has a higher wax content than the outer parts and conducts sound more slowly.

[7] The speed of sound in the melon is lowest in the Delphinidae, Phocoenidae, and Monodontidae, intermediate in the Ziphiidae (beaked whales), and highest in the Physeteridae and Platanistidae (South Asian river dolphins).