Most trees grow vertically straight, but under challenging conditions where individuals have to compete for light, or when mechanical stress is intense, trees may grow at an angle.

Araucaria columnaris, or Cook pines —named after Captain James Cook, whose second voyage around the globe carried the first botanists to classify the tree— is a tree endemic to New Caledonia in the Melanesia region of the southwestern Pacific Ocean, but have since been planted in temperate, subtropical, and tropical areas throughout the world. When grown outside of its native range, the Cook pines have a pronounced lean that’s so ubiquitous that it is often used as the identifying characteristic for the species. But until recently, nobody paid much attention to which direction it leaned or by how much.