The brain, though contained by our skull, contains so many neurons that, if they were stretched end-to-end, they would reach all the way to the moon. This episode discusses various animal brains, as well as how our own brains work.
Tropes:
- All Cavemen Were Neanderthals: In discussing the human brain, Neanderthal Jumbo and Neanderthal Pest are shown.
- Continuity Nod: The intro shows a Stegosaurus, as well as Jumbo and Pest in their "Neanderthal Man" forms.
- Good Angel, Bad Angel: Played with. By the end of the episode, Le Teigneux and Nabot try to provoke Jumbo. Jumbo's devil is shown as a crocodile, while his angel is off-screen, only represented by a calm voice.
- Never Smile at a Crocodile: The crocodile is used to represent the reptilian brain.