A Psychotropic Fungus Is Eating Away Cicadas' Genitalia and Boosting Their Sex Drive

WerksMedia, iStock / Getty Images Plus
WerksMedia, iStock / Getty Images Plus

A droning sound that fills your backyard at volumes exceeding 100 decibels is a sign that the cicadas have emerged for the summer. The noisy bugs have one of the most fascinating lifecycles of any insect species—spending up to 17 years of their lives underground as nymphs before finally crawling to the surface, molting their exoskeleton on the first elevated surface they can find, and mating as mature adults for a few weeks before expiring. As The New York Times reports, a recent phenomenon observed by scientists is making this process even stranger. Many cicadas have fallen victim to a psychotropic fungus that invades their bodies and compels them to keep mating even after their genitals have been replaced with fungal spores.

A study recently published in the journal Fungal Ecology explores how exactly the fungus is able to prey upon its hosts. Massospora is a genus of fungi that lives in the soil where young cicadas spend the first part of their lives. A cicada that digs through dirt containing Massospora emerges contaminated with fungal spores. The spores proliferate as the insect matures, eventually eating through its abdomen and destroying its reproductive system.

But the goal of the fungus isn't to kill its host immediately. Even when two thirds of a cicada's body is made up of Massospora, it continues to fly around, committed to its purpose at the end of its life—reproducing—seemingly more than ever. And when it tries to mate, the white clump of spores where its genitals should be can potentially infect a new victim.

The researchers could see how Massospora spread from cicada to cicada, but why the cicadas were driven to keep mating in such poor condition was more of a mystery. Their paper points to psychotropic substances found in the fungus—including the same compound that makes magic mushrooms a Schedule 1 drug.

The spore plugs of infected cicadas contain psilocybin, the hallucinogen in magic mushrooms; and cathinone, an amphetamine found in the East African khat plant. When the researchers sequenced the genomes of Massospora, they found that the fungus didn't contain either the genes used by magic mushrooms or khat to produce their mind-altering substance. This could mean that the cathinone and psilocybin found in the spore plugs are the products of a chemical reaction between the fungus and something in its cicada host, possibly the bacteria in the insect's gut. The two compounds also appeared independently in different types of cicadas: annual cicadas were effected by psilocybin, and periodical cicadas, which include 17-year and 13-year cicadas, contained cathinone.

In people, psilocybin has been shown to combat symptoms of depression and anxiety, while cathinone can improve focus in people with ADHD. It's possible that some version of these effects are amping up the infected cicada's sex drive. In their drugged-out stupor, the host insects seem hyper-focused on mating, even though they're unable to reproduce. It's easy to see how this benefits Massospora: The more cicadas its host tries to copulate with, the more insects are exposed to its spores. Why cicadas would have evolved to synthesize the narcotics in the first place is less clear.

[h/t The New York Times]

The Horrors of Anglerfish Mating

Masaki Miya et al. "Evolutionary history of anglerfishes (Teleostei: Lophiiformes): a mitogenomic perspective," BMC Evolutionary Biology 10, article number: 58 (2010), Wikimedia Commons // CC BY 2.0
Masaki Miya et al. "Evolutionary history of anglerfishes (Teleostei: Lophiiformes): a mitogenomic perspective," BMC Evolutionary Biology 10, article number: 58 (2010), Wikimedia Commons // CC BY 2.0

When you think of an anglerfish, you probably think of something like the creature above: Big mouth. Gnarly teeth. Lure bobbing from its head. Endless nightmares. 

During the 19th century, when scientists began to discover, describe, and classify anglerfish from a particular branch of the anglerfish family tree—the suborder Ceratioidei—that’s what they thought of, too. The problem was that they were only seeing half the picture. The specimens that they were working with were all female, and they had no idea where the males were or what they looked like. Researchers sometimes found some other fish that seemed to be related based on their body structure, but they lacked the fearsome maw and lure typical of ceratioids and were much smaller—sometimes only as long as 6 or 7 millimeters—and got placed into separate taxonomic groups.

It wasn’t until the 1920s—almost a full century after the first ceratioid was entered into the scientific record—that things started to become a little clearer. In 1922, Icelandic biologist Bjarni Saemundsson discovered a female ceratioid with two of these smaller fish attached to her belly by their snouts. He assumed it was a mother and her babies, but was puzzled by the arrangement.

“I can form no idea of how, or when, the larvae, or young, become attached to the mother. I cannot believe that the male fastens the egg to the female,” he wrote. “This remains a puzzle for some future researchers to solve.”

When Saemundsson kicked the problem down the road, it was Charles Tate Regan, working at the British Museum of Natural History in 1924, who picked it up. Regan also found a smaller fish attached to a female ceratioid. When he dissected it, he realized it wasn’t a different species or the female angler’s child. It was her mate.

The “missing” males had been there all along, just unrecognized and misclassified, and Regan and other scientists, like Norwegian zoologist Albert Eide Parr, soon figured out why the male ceratioids looked so different. They don’t need lures or big mouths and teeth because they don’t hunt, and they don’t hunt because they have the females. The ceratioid male, Regan wrote, is “merely an appendage of the female, and entirely dependent on her for nutrition.” In other words, a parasite.

When ceratioid males go looking for love, they follow a species-specific pheromone to a female, who will often aid their search further by flashing her bioluminescent lure. Once the male finds a suitable mate, he bites into her belly and latches on until his body fuses with hers. Their skin joins together, and so do their blood vessels, which allows the male to take all the nutrients he needs from his host/mate’s blood. The two fish essentially become one.

With his body attached to hers like this, the male doesn't have to trouble himself with things like seeing or swimming or eating like a normal fish. The body parts he doesn’t need anymore—eyes, fins, and some internal organs—atrophy, degenerate, and wither away, until he’s little more than a lump of flesh hanging from the female, taking food from her and providing sperm whenever she’s ready to spawn.

Extreme size differences between the sexes and parasitic mating aren’t found in all anglerfish. Throughout the other suborders, there are males that are free-swimming their whole lives, that can hunt on their own and that only attach to the females temporarily to reproduce before moving along. For deep-sea ceratioids that might only rarely bump into each other in the abyss, though, the weird mating ritual is a necessary adaptation to keep mates close at hand and ensure that there will always be more little anglerfish. And for us, it’s something to both marvel and cringe at, a reminder that the natural world is often as strange as any fiction we can imagine.

Naturalist William Beebe put it nicely in 1938, writing, “But to be driven by impelling odor headlong upon a mate so gigantic, in such immense and forbidding darkness, and willfully eat a hole in her soft side, to feel the gradually increasing transfusion of her blood through one’s veins, to lose everything that marked one as other than a worm, to become a brainless, senseless thing that was a fish—this is sheer fiction, beyond all belief unless we have seen the proof of it.”

This Automatic Fetch Machine Will Keep Your Dog Occupied When You Don't Have Time to Play

iFetch
iFetch

Every dog owner knows that it's impossible to keep up with a pooch that's always looking to play. But if you want to keep them active while still having time for yourself, there's the iFetch, a toy that will automatically throw tennis balls, allowing your canine to play fetch whenever they please.

You can find the iFetch Original, which is ideal for small or medium dogs, on Amazon for $115. The Original can either be charged with an AC adapter or run on six C batteries, both of which are included. You can adjust the settings on the iFetch to throw the ball 10, 20, or 30 feet, making it perfect for indoor or outdoor play. Once it's charged and the distance is set, let your canine drop a tennis ball into the machine and it will take care of the rest.

If you have a large dog, look for the iFetch Too, which is available on Amazon for $200. This model has a rechargeable battery that can last up to 300 throws. This model can launch the ball 10, 24, or 40 feet, and it also comes with a custom option, so you’ll find room for your dog to play no matter how much space is available.

If your dog loves their new toy, but you don't love finding slobbery tennis balls around the house, check out the company’s medium- and small-size slobber-proof balls.

It may take time for your canine to learn how to use the toy, but the company has some training tips from Nicole Ellis, a certified professional dog trainer. To start, it's recommended that your dog knows the “drop it” command. If they don’t, check out their training tips here. After your dog has mastered that command, the company has plenty of tricks, such as keeping training sessions short and ending them on a positive note. For more ideas, check out their page.

Once you set up your iFetch and watch your furry friend run back and forth, you may start to wonder why they like fetch so much. According to research on the subject, when dogs exercise, neurotransmitters stimulate reward regions in their brain, which is much like when humans experience a "runner's high."

If you happen to notice your canine seems particularly athletic while they are chasing the ball back and forth, check out these other sports they can play.

Mental Floss has affiliate relationships with certain retailers and may receive a small percentage of any sale. But we choose all products independently and only get commission on items you buy and don't return, so we're only happy if you're happy. Thanks for helping us pay the bills!

SECTIONS

arrow
LIVE SMARTER