There are also several similarities in the behavior of Greys and dolphins. Terran dolphins use sonar both to navigate and stun prey and enemies. The stun affect is of particular interest in this case. Dolphins can emit very powerful and focused ultrasonic bursts from the anterior section of their skulls, from an organ known as a 'melon'. This is used to stun prey and enemies, such as sharks and barracuda. There has been an excellent film created by a group of students while diving, illustrating a group of dolphins utilizing this ability on a very large barracuda. The barracuda was swimming towards a group of very young dolphins. Four large adult dolphins turned so that there heads were directly aligned with the barracuda, and emitted a sustained ultrasonic burst. The effect on the barracuda was astounding. It literally froze, completely paralyzed in the water, and even the gills ceased to move. The dolphins stared at it for about thirty seconds, during which time the barracuda remained totally immobilized. As soon as they turned their heads away, the ultrasonic beam was no longer focused on the barracuda, whereas it fled at a very high rate of speed from the scene. Obviously, this beam was tightly focused, and required the dolphin's head to be pointed directly at the target. The strength of the beam could be changed as well. When hunting, the ultrasound beam could be directed at small fish and amplified to lethal levels, causing instant death. Some cetacean researchers believe that this is also used when dolphins ram sharks. Autopsies of the shark corpses after a dolphin attack reveal the sharks internal organs have been visibly shattered. The beam can also be controlled so as to produce a stun effect, as in the case of the barracuda. The result was physical paralysis and disorientation. This phenomenon is very similar to the technique used by the Greys as an aid to telepathic control of abductees. The similarities are almost overwhelming. Nearly every abductee states that when they are abducted, they are paralyzed by the Greys, and become mentally disorientated. The most striking thing most recall is what is known as the 'Stare.' This occurs when a Grey looks directly at an abductee, whereas the large, dark eyes capture the abductee's attention immediately. Abductees then report being unable to move, and a feeling of great mental disorientation. On some rare occasions, abductees report a lessening of these effects when a Grey looked slightly away from them. This clearly indicates that the intensity of the effect was directly proportional to the direction or focus of the front portion of the Grey head. This evidence leads to the hypothesis that the Greys use a kind of ultrasonic sound beam in conjunction with telepathy to paralyze an abductee during an abduction.

The 'Stare" as abductees call it, is merely the positioning of the Grey's anterior skull area, the projection area where the Grey equivalent to the cetacean 'melon' is located, to achieve maximum beam concentration on the abductee. When the Grey looks away, the beam would naturally become less focused and the effect would diminish, just as it appears when the Grey is distracted momentarily. The description of the Grey's head is usually large, triangular and rounded in front and back. This suggests a large and rounded rear and frontal brain lobe structure. This is exceedingly similar to the physical structure of a cetacean brain. It is the main difference between cetacean and human brains. This large rounding is thought to be an adaptation of the cetacean brain to handle the enormous data flow received from echo-location and other sound-based communications faculties. It should also be noted that on the rare occasions that abductees hear verbal sounds from Greys, it is described as high-pitched, sometimes chattering or staccato clicks or beeps. These are all similar to the air vocalizations of dolphins. While the brain structure of the Greys has remained basically constant, it can be assumed that the echo-location ability of the Greys would have been decreased or atrophied almost completely. After all, there is probably little use for echo-location is such a society, thus it could have been bred out of the species during cloning.