We humans are smart, to be sure, but if we’re so smart then how come we can’t figure how we got so smart in the first place? Think about that! We sure did and we go over some theories in this super interesting episode.

Selects: Mangroves: Nature's Best Tree?
44:31

How the Kowloon Walled City Worked
41:27

Short Stuff: In-Flight Entertainment
12:23