A strange fungus could transform emerging cicadas into ‘saltshakers of death,’ scientists say

Kate Golembiewski, CNN

(CNN) — This spring, billions of cicadas will emerge aft much than a decade underground, fresh to climb into nan trees and make a ruckus arsenic they singing to pull mates. But immoderate of these insects won’t win successful their extremity of procreating — instead, they’ll beryllium controlled for illustration zombies into spreading a unusual fungus that hijacks cicadas’ bodies and behavior.

The specifications of nan fungus’ onslaught connected nan bugs — destroying nan insects’ genitals, replacing their abdomens pinch a cavity afloat of fungal spores, manipulating nan bugs into hypersexual behaviour to dispersed nan fungus further and transforming nan cicadas into what immoderate scientists word “saltshakers of death” — whitethorn look for illustration they beryllium successful a animal characteristic scary movie. But erstwhile it comes to nan fungus Massospora cicadina, said Dr. John Cooley, an subordinate professor successful residence of ecology and evolutionary biology astatine nan University of Connecticut, Hartford, “the truth is really overmuch alien than subject fiction.”

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Periodical cicadas laic their eggs successful character branches, and erstwhile those eggs hatch, nan resulting babe cicadas, aliases nymphs, driblet to nan crushed and burrow into nan soil. Depending connected their species, they walk 13 aliases 17 years underground, drinking sap from character roots, until it’s clip for nan astir grown cicadas to emerge. At immoderate point, nan insects are exposed to spores of nan fungus Massospora cicadina. It’s not clear to scientists whether it happens erstwhile nan cicadas participate nan ungraded aliases erstwhile they time off it, aliases really that vulnerability happens.

How Massospora cicadina controls cicadas

The spores make their measurement into nan cicadas’ bodies, and from that constituent on, nan cicadas are astatine nan mercy of nan fungal parasite. A wide of fungal spores builds up successful nan abdomen of each infected cicada. Eventually, nan backmost extremity of nan cicada — including its genitals — falls off. In its place, a achromatic fungal plug is exposed, “a clump of spores that are erupting retired of wherever nan genitals and abdomen erstwhile were,” said Dr. Matt Kasson, an subordinate professor of mycology and wood pathology astatine West Virginia University. “It looks for illustration there’s a gumdrop that’s been dropped successful chalk dust, glued to nan backside of these cicadas.”

“There’s a cicada stepping astir pinch personification else’s genitals stuck to them.”

Despite having a chalky gumdrop of spores alternatively of genitals, nan infected cicadas still effort to mate, pinch gusto. The fungus manipulates nan cicadas’ behavior, causing what researchers, including Kasson, mention to arsenic hypersexualization. The infected males support trying to mate pinch females, and they besides alteration their behaviour to pull their chap males. Healthy female cicadas will flick their wings to bespeak that they’re fresh to mate. Both antheral and female cicadas infected pinch Massospora flick their wings to tie successful amorous, soon-to-be-infected males.

But attempting to mate is conscionable 1 portion of really infected cicadas dispersed nan fungus.

“Periodical cicadas person interlocking genitalia. So erstwhile they propulsion apart, conjecture what happens? Rip. And past there’s a cicada stepping astir pinch personification else’s genitals stuck to them,” Cooley said. “And now nan cicada that’s infected is busted open.”

Researchers clasp a cicada infected pinch nan fungus Massospora cicadina. | Angie Macias, WVU via CNN Newsource

Once nan chalky fungal plug is ripped apart, nan infected and disemboweled cicada flies around, raining down fluffy, brownish spores. “We telephone them nan saltshakers of death,” Kasson said. The spores dispersed by these flying saltshakers spell connected to infect nan adjacent procreation of cicadas that will look much than a decade later and statesman nan rhythm again.

Zombie cicadas stimulated by an amphetamine?

It’s an atrocious batch of moving astir and mating for animals whose bodies person been torn apart. Kasson and his colleagues have recovered a imaginable explanation for what keeps these cicadas going. “We recovered an amphetamine successful those fungal plugs, which provides a plausible mentation arsenic to why nan behavioral modification is occurring,” Kasson said. After all, amphetamines are powerful stimulants successful humans.

Cooley noted that while amphetamines stimulate nan cardinal tense systems of vertebrate animals, insects (which are each invertebrates) specified arsenic cicadas person different tense systems, and it’s not clear if those stimulants would impact them nan aforesaid way.

“We’re near pinch this problem, that it’s making a powerful psychoactive chemical, but nan powerful psychoactive chemic whitethorn not do thing to nan insects,” Cooley said. He suggested that nan fungus whitethorn person a different intends of controlling nan cicadas’ behavior, and that nan amphetamines it produces mightiness alternatively service to ward disconnected vertebrate predators of cicadas (and thus, of cicada-dwelling fungi), specified arsenic birds.

This spring’s periodical cicada emergence is noteworthy because two different broods will look simultaneously successful neighboring regions — 17-year cicadas concentrated successful bluish Illinois, and 13-year cicadas passim overmuch of nan Midwest and Southeast. These 2 broods person not been aboveground astatine nan aforesaid clip since 1803; however, scientists expect small geographical overlap of nan 2 broods.

Kasson said he hopes to study infected insects from nan 2 different broods and spot whether location are familial differences betwixt nan M. cicadina infecting nan 17-year and 13-year broods.

While cicadas are edible, Kasson said group hoping to sample nan bugs should beryllium choosy astir which ones they eat. If you find big cicadas adjacent nan extremity of their lives, aliases already dead, Kasson said, “you do not want to put those successful your mouth,” sloppy of whether they’re infected pinch M. cicadina. If a person, canine aliases feline were to eat an infected cicada, they wouldn’t beryllium affected by nan amphetamines successful it — nan dose is excessively small. And for “The Last of Us” fans, M. cicadina is only tin of infecting cicadas (and conscionable nan 13- and 17-year varieties of these bugs), truthful humanity is astir apt safe from zombification.

Kasson said that while he understands nan trepidation group mightiness person astir nan upcoming cicada emergence, not to mention nan grotesque fungal infection that up to 10% of them mightiness develop, he noted, “It’s a biologic spectacle. And I deliberation we should conscionable admit this arsenic 1 of nan earthy wonders of nan world.”

Kate Golembiewski is a freelance subject writer based successful Chicago who’s particularly willing successful zoology, thermodynamics and death.

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