It’s not just a monkey puzzle, it’s a hydrodynamics puzzle. The spiky leaves of the tree also known as the Chilean pine confound not only the hands of primates, scientists have found, but also the brains of fluid dynamicists.
If you drip water on to the leaves of araucaria trees, the genus that includes the monkey puzzle, then it flows in one direction and one direction only. Drip ethanol on to it, researchers discovered to their amazement, and it goes in the other.
The finding, said Zuankai Wang, from City University of Hong Kong, “was like a miracle”. Despite the ubiquity of the ornamental plants, “this was the first recorded observation in the scientific world”.
In a paper in the journal Science, he and