This is a great breakdown on the nature, cause, and avoidance of different kinds of turbulence (thermal, mechanical, aerodynamic, shear). This gets a gold star for being classic "Finer Points" material. Highly recommended.
I have been in the right seat teaching when a wasp came out of the fresh air vent and stung the pilot. As an instructor, I have to tell you, it's amazing. You wish all your students could have that sort of experience of needing to fly the airplane first and deal with something very urgent seeming second. I'm not deranged enough to actually put bees in the airplane, but it's tempting. Reading this author's experience, I think seeing bees, but not getting stung, is probably more dangerous than getting stung by a bee you never saw.