Researchers in West Virginia discovered that the local cicadas were infected by a mind-controlling fungus that caused them to act early to facilitate the spread of the disease, exhibiting what was described as “hypersexual behavior.” Parts of the insects’ bodies are replaced by the fungus that just dried away, while the fungus keeps the deadly wounded cicada alive.
Researchers in West Virginia have discovered that about one-third of the cicadas, small winged insects that appear each year, are under the influence of Massospora, a psychedelic fungus that contains chemicals similar to those found in hallucinogenic mushrooms. The chemicals cause the infected cicadas to nurture other cicadas to facilitate the spread of the fungus, manipulating male cicadas to flicker their wings like females – an invitation to mate – which requires and infects terribly male cicadas. The study, “Behavioral Betrayal: How Select Mushroom Parasites Invite Insects to Make Their Offers,” was published in the journal PLOS Pathogens.
“Essentially, the cicadas lure others to become infected because their healthy colleagues are interested in mating,” said Brian Lovett, co-author and postdoctoral researcher at Davis College of Agriculture, Natural Resources and Design. “The bioactive compounds can manipulate the insect to stay awake and transmit the pathogen for longer.”
In true horror movie fashion, Massospora spores knead away at genitals, buttocks and stomach of a cicada, and replace them with fungal spores. Then “wear them away like a glue on a pencil,” Lovett said.
The fungus manipulates the behavior of the insects to keep the host alive instead of killing them to maximize spore spread.
“If one of our limbs were removed or if our stomach was opened, we would probably be awkward,” said co-author Matthew Kasson CNN. ‘But infected cicadas, despite the fact that a third of their body has fallen, continue with their activities such as mating and flying as if nothing had happened. This is really, really unique to fungi with killing insects. ”
Even though infected cicadas compare their ability when their hindquarters are replaced by the fungus, they will still try to pair to sexually transmit the fungus to healthy cicadas in what researchers describe as “hypersexual behavior.”
“When they fly around or walk on branches, they also spread spores that way,” Kasson said. “We call them flying salt shakers of death, because they basically spread the mold the way salt would come out of a shaker that turns over.”
Lovett compared the transmission of the behavior-altering virus to rabies.
Both rabies and entomopathogenic fungi (parasites that kill insects) increase their live hosts for successful ‘active host transmission’, Lovett said.
“When you are infected with rabies, you become aggressive, you become afraid of water and you do not swallow,” Lovett said. “The virus is transmitted by saliva and all these symptoms actually turn you into a machine with the spread of rabies, where you are more likely to bite people.
“In that sense, we are all very familiar with active host transmission. Since we are also animals like insects, we want to think that we have complete control over our decisions and we take our voluntariness as applicable. But when these pathogens infect cicadas, it is very clear that the pathogen attracts the behavioral cigars of the cicadas to cause it to do things that are not in the interest of the cicada, but very much in the interest of the pathogen are. “
As bizarre as the infection sounds, it is generally harmful to humans and cicadas. The insects reproduce at such a rate that the control of fungi by hordes of cicadas does not have much effect on their total population.
“They’re very decent,” Lovett said. ‘You can walk right up to one, pick it up to see if it has the mold (a white to yellow plug on the back end) and put it down. They are by no means a major plague. They are just a really interesting insect that developed a bizarre lifestyle. ”
Cicadas have a life cycle of 13 or 17 years and live underground until they emerge more than a decade later, studying how Massospora infects these species can be very difficult.
