The Monkey-Puzzle Tree
A striking example of spines for protection, this tree bears but few seeds and protects them, with a spiny armor, from destruction by monkeys. The nuts are borne at, or very near the top, and the spines are so sharp that it is impossible for any animal to climb the tree. Where the cactus spines are designed to protect the plant itself, the monkey-puzzle spines are designed to protect the offspring of the plant, represented by its seed.
This image is from: Luther Burbank: his methods and discoveries and their practical application. Volume 1 Chapter 1