Give a new (central, top) leaf the number 1, and now count out/downward. See, how the difference between neighboring numbers show Fibonacci numbers, e.g. 11-3=8. But look also at all of the three neighbours of 10. The neighbors differ by 3, 5, and 8.

The angles between successive leaves are Golden Angles, or about 137.5º.

360/222.5≈222.5/137.5≈phi