Some plants want ample water and sunshine. The plant Nepenthes rafflesiana, however, desires the droppings of Hardwicke’s woolly bats.
The carnivorous plant and the key-sized tiny bat live on the Indonesian island of Borneo, where their unusual arrangement has blossomed. Scientists who placed trackers on the backs of the bats found that they nap away their days nestled in the pitcher of this pitcher plant, and they use it as their personal commode. That’s just fine for the pitcher plant, which doesn’t trap as many bugs as its relatives, but makes up for it by deriving one-third of its nutrients from bat excrement.
“It’s totally unexpected,” said Ulmar Grafe, an associate professor at the Universiti Brunei Darussalam who led the study. “There’s a lot of animal-plant mutualisms, but this one is where the animal gives a nutrient to a plant. Usually it’s the other way around.” [Reuters]
You might think it’d be dangerous for bats to lay around in a plant’s pitcher, where they could plummet into the gooey nectar the plant uses to trap and eat insects. But, in fact, the pitcher is shaped just right so that the bats can’t fall through. Says Grafe: