Fruit body of a parasitic fungus, growing out of a dead ant.
An unlucky ant inhales a spore, the fungus begins to eat the ant from inside, and, in a particularly sinister twist, Ophiocordyceps hijacks the ant’s brain. The “zombie” ant is forced to leave its nest to climb up onto a tree, clamping its jaws into a leaf vein with abnormal force. A stalk sprouts from the now dead ant’s head. This stalk is fruiting body of the fungus, which will produce new spores that rain down onto the unlucky ants below.
Ophiocordyceps seems like a lean mean killing machine in that scenario, but the fungus itself is vulnerable—to another fungus it turns out. A new paper published in PloS ONE models the disease dynamics of Ophiocordyceps with respect to ants and a hyperparasitic fungi, which is the name for parasite whose host is also a parasite. Unfortunately, this hyperparasite is not of much help for the ant, as it only infects the Ophiocordyceps after the ant has died.
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: