At first I was shocked because I thought he had pulled the brain out of one species and placed it in the skull of another. Then I learned it was between two fish of the same species with some minor environmental adaptations (the statement about their brains being as different as human and ape brains is completely ridiculous, please don't get me started). Then I learned he didn't switch brains by means of an operation at all. He just changed gene expression, which made it "look" like the brain of the other fish.
Meh. The line about the mouse was more interesting.

Don't forget to watch their other videos:
Positioning Systems II - From Point A to Point B
Wheels and Cogs - Working Normally
Metronomes Without Music
and
Water Meters in Action

I'm guessing R2 is Batman and C3P0 is Robin, because I just can't see it the other way around.

What evolution took place here? The fish have not evolved into something other than fish, but to the contrary have mutated resulting in loss of genetic information.

It's a conspiracy. No one really walked on this "Mars" and there are clearly no glowing green plumbobs above those sims. Fake.

Actually, the first character is turned upside down...Not smart, indeed.

What I want to know is, how do you put it in reverse?!