An excellent video series by Vi Hart on Fibonacci numbers hiding in other strange places (and spirals and plants): Part 1: https://www.youtube.com/watch?v=ahXI

An excellent video series by Vi Hart on Fibonacci numbers hiding in other strange places (and spirals and plants): Part 1: https://www.youtube.com/watch?v=ahXIMUkSXX0 https://www.youtube.com/watch?v=ahXIMUkSXX0 Part 2: https://www.youtube.com/watch?v=lOIP_Z_-0Hs https://www.youtube.com/watch?v=lOIP_Z_-0Hs Part 3: https://www.youtube.com/watch?v=14-NdQwKz9w https://www.youtube.com/watch?v=14-NdQwKz9w