Tursiops truncatus left dorsolateral view

This left dorsolateral view of a bottlenose dolphin (Tursiops truncatus) was reconstructed from X-ray CT scans.  The structures displayed within the head are components of the bioacoustic system and are shown in various colors. 

Skull=white.   Structures above the skull are: melon=yellow, melon core=orange, bursae=red, bony nasal passages=blue.  Structures below the skull are: mandibles (lower jaws)=beige, mandibular fat bodies=green, ear complexes (tympanoperiotic complexes)=purple.

The melon, melon core, bursae, mandibular fat bodies are all made of fat and are part of the sound transmission pathways into and out of the head.  For example, sonar sounds are transmitted out through the melon and echos are received through the mandibular fat bodies to the ear complexes.  Bony structures (e.g. skull and mandibles), air spaces, and dense connective tissues (theca) function as sound reflectors in the bioacoustic systems of these animals.

(Tutr0790uu)