Given how difficult it can be to communicate within our own species, it’s not surprising that we are just learning of the amazing conversations that are happening between other species. For example, local species of bats in Borneo and Nepenthes hemsleyana, a large, carnivorous pitcher plant, have developed a unique, symbiotic relationship based on communication. According to a recent study published in the journal Current Biology, ultrasonic signals emitted by the bats are reflected by the pitcher plants, which allows the bats to locate a relaxing spot to rest. In return, the pitcher plants receive a nutritional feast from the bat’s guano (poop).
Pitcher plants serve as an ideal receptor for ultrasonic mammalian messages because of their unique form. “With these structures, the plants are able to acoustically stand out from their environments so that bats can easily find them,” says Michael Schöner, researcher at Ernst-Moritz-Arndt-University of Greifswald and co-author of the report. “Moreover, the bats are clearly able to distinguish their plant partner from other plants that are similar in shape.” Curious why the bats seem so adept at locating the pitcher plants, the researchers used an artificial biomimetic bat head, which emitted ultrasonic signals, to test the plant’s ability to bounce back the waves. As the experiments reveal, the acoustically-shaped plant is a perfect receptor for bat signals.
Researchers have long wondered why Nepenthes hemsleyana has not as vigorously consumed insects as other pitcher plants. This study offers the answer: it receives its nutrients from the rich waste product of bats. Like other plants, carnivorous plants create their own energy through photosynthesis. However, meat-eating veggies lack an interest in acquiring nutrients from the soil. Instead, they absorb what they need to grow from animal sources.
Although lacking a central nervous system, plants have managed to problem solve their way out of many evolutionary challenges. “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,” says Schöner. “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.” Poison Ivy would be proud.