GREIFSWALD, Germany, July 9 (UPI) -- The leaves of a pitcher plant species in Borneo serve as a sounding board for the sonar of resident bats, attracting the furry, flying mammals to hang out -- and poop.
By using special sonar-bouncing leaves, the plant makes itself easier to find, thus increasing its odds of being fertilized by bat droppings.
"With these structures, the plants are able to acoustically stand out from their environments so that bats can easily find them," researcher Michael Schoner, a scientist at Germany's Ernst-Moritz-Arndt-University of Greifswald, explained in a press release. "Moreover, the bats are clearly able to distinguish their plant partner from other plants that are similar in shape but lack the conspicuous reflector."
Schoner is the lead author of a new study on the pitcher plant's leaves, published in the journal Current Biology.
Just as animals develop unique adaptations and specialized traits to outcompete their rivals for mates and food, plants too are locked in a never-ending competition for resources. Quality fertilizer is one of the those resources, and bat poop is especially rich in plant-boosting nutrients.
But standing out in the lush, crowded forests of Borneo, South East Asia's largest island, is difficult. For one species of pitcher plant, Nepenthes hemsleyana, curved, soap dish-like leaves are the answer. As tests showed, the cupped leaves offer a strong backboard for reflecting sonar, sending back out an echo that bats can easily recognize.
Developing these leaves has cost the carnivorous plant some of its ability to attract insects to digest, but the extra bat poop makes up for the losses. Fewer bugs turns out to be a good way to keep the Kerivoula hardwickii bat coming back. The species enjoys hanging out on plants where fewer pests and parasites reside.
"Carnivorous plants in general have already solved the problem of nutrient deficiency in a very unusual way by reversing the 'normal system' of animals feeding on plants," Schoner said. "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," he added, "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."