Why can’t we all just get along like bats and carnivorous plants do? It’s true … a meat-eating plant in Borneo signals its location to bats that hang from its sides and fertilize the ground with their guano.
This unusual bat/plant mutual cooperation relationship is described in a study published in the latest edition of Current Biology. Researchers led by Michael Schöner of Ernst-Moritz-Arndt-University of Greifswald in Germany were originally trying to figure out why Nepenthes hemsleyana, a large, carnivorous pitcher plant native to Borneo, seemed to be growing so … large.
This is unusual since meat-eating plants are often undernourished due to a lack of bugs and other living creatures to eat. When they found the bats hanging around the plants, they quickly determined that the bat droppings, rich in nutrients, were providing the plants with fertilizer they wouldn’t normally get.
But why were the bats there in the first place? The researchers suspected it had something to do with the shape of the pitcher plant. To test this theory, they created an artificial biomimetic bat head that emits and records ultrasounds (I’ve got to get one of those!). They pointed the head at a plant from various directions and angles and picked up the strongest reflective signals from the back wall of the pitcher … where the real bats hang out because it’s cool and away from the toxins the plant uses to kill its prey.
That caused the researchers to notice something else … the plants didn’t seem to be killing many bugs. They believe the Nepenthes hemsleyana has evolved to depend on the bat poop for primary nourishment and relies on bugs for backup (and dessert?). Schöner sounds pretty excited about this discovery:
It is even more astonishing that in the case of N. hemsleyana the system is taking a new turn. While N. hemsleyana reduced many insect-attracting traits, it obviously exhibits some traits that are highly attractive for a species that provides the plants with nutrients without being digested by the plant itself.
Personally, I’d be more excited about driving bugs batty with the artificial bat head.