Forehead, fivehead, threehead

Aeluga, Beluga, Celuga

I don’t have one I just love that this structure is called a melon. 🍉

The melon is a mass of adipose tissue found in the foreheads of all toothed whales.[1][2] It focuses and modulates the animal's vocalizations and acts as a sound lens. It is thus a key organ involved in communication and echolocation.

https://en.m.wikipedia.org/wiki/Melon_(cetacean)

Cranial capacity classes:

A: Average.

B: People who thank the bus driver.

C: Elon Musk.

When you're prairie dogging it but there's no bathroom around, so you suck it back up.

a. W

b. T

c. F

So long, and thanks for all the fish

Percolating

Head bubbling

Wait; Did his head deform? So I caption it: Head deformation in swimming mammal.

"You Won't Believe What This Beloved Fish Can Do With A Cherry Stem!"