People the world over have a good sense that flies are filthy and that we do not want them landing on our food during our summer picnics. Research has justified that disgust, showing that flies associated with humans and their livestock spread a diversity of pathogens. In a collaboration with Roman Wittig of the Max Planck Institute for Evolutionary Anthropology and the Taï Chimpanzee Project, a research team led by Fabian Leendertz at the Robert Koch Institute in Germany has now shown that such fly associations also exist in highly mobile non-human primate groups as they move kilometers every day through the rainforest.
The researchers first looked at fly densities inside and outside groups of wild sooty mangabeys and chimpanzees in Taï National Park, finding many more flies in primate social groups than outside them. First author Jan Gogarten then carried out a quirky experiment to understand how this high density of flies was maintained, marking over 1,700 flies with nail polish in a group of mangabeys. To their surprise, the researchers recaptured these colorful flies in the mangabey group up to two weeks later and nearly a kilometer and a half from where they were marked. "These surprising results suggest there is a high density fly cloud following monkeys as they move kilometers each day through the forest", says Gogarten.
Read more at Max Planck Institute for Evolutionary Anthropology
Image: Fly clouds are following sooty mangabeys through the forest and may spread disease among them. (Credit: Jan Gogarten, Taï Chimpanzee Project)