In the rainforests of Chile and Argentina lives a vine that camouflages itself by mimicking the tree it climbs on. But Boquila trifoliolata doesn’t just evolve to look like its host. It doesn’t pick trees that it resembles. It actually changes its leaf shape when it grows up a tree! A single vine will have a certain shape leaf while it grows across the ground, and then a different shape growing from the parts of the vine that climb a tree. And a single Boquila vine can have several different leaf shapes as it grows from tree to tree. Why does it do that?
The probable answer is that it keeps it from being eaten.
The forest is full of leaf-eaters. Imagine a hungry caterpillar wandering up to a tree:
It loves eating leaves. It might find vine leaves extra tasty. But if our vine is hiding among the many, many leaves of the tree, each vine leaf has a smaller chance of being chewed on.
Or maybe the vine is assuming the shape of leaves that are toxic to the caterpillar. This is called Batesian mimicry, when a harmless species tries to look like a very bad meal.
Whatever the reason, mimicry seems to work. Gianoli and his co-author, Fernando Carrasco-Urra, reported that when the vine is mimicking its neighbors higher up, it gets chewed on less.
The real question is how the “stealth vine” achieves its mimicry. How does a plant without eyes know what the surrounding leaves look like? Scientists have no concrete answers, but they have some ideas of what might be going on. Read about those theories at Phenomena. -via Digg
(Image credit: Robert Krulwich)