Part 1: youtu.be/ahXIMUkSXX0 Part 3: youtu.be/14-NdQwKz9w More on Angle-a-trons: www.youtube.com/watch?v=o6W6P8JZW0o Here is a program that draws plant leaves at whatever angle you want: www.khanacademy.org/cs/plant-leaves/822940457 Note: Beautiful spirally non-Fibonacci pinecones are very rare! If you find one, keep it. My personal website, which you might like: vihart.com