A common pathogenic fungus called Entomophthora muscae lives by infecting common houseflies with lethal spores.
Research now revealed that the fungus has a special strategy to secure its life.
When exposed to the fungal-infected carcasses of dead females, the fungus "bewitches" male houseflies and induces necrophilia in them.
Dead flies become attracted by fungi
The fungus spreads after infecting a female fly with its spores until the victim is gradually devoured alive from within.
The fungus takes control of the female fly's behavior after about six days and drives it to the highest place, such as a wall or some plants, where it dies.
After the zombie female is dead, the fungus starts to emit sesquiterpenes, which are chemical messengers.
Henrik H. De Fine Licht, an associate professor at the University of Copenhagen's Department of Environment and Plant Sciences and one of the study's authors, explained that the chemical signals function as pheromones that seduce male flies and give rise to an intense desire for them to mate with dead female carcasses.
The researchers were able to show that deceased female flies gain in attractiveness over time by monitoring fly behavior.
Particularly, 73% of the male flies in the research mated with female fly corpses that had perished between 25 and 30 days previously due to the fungus.
Only 15% of the males mated with three to eight hour-old female corpses.
According to Licht, "We discover that a female fly gets more tempting to males the longer it has been dead because the amount of fungal spores grows with time, which amplifies the seductive smells," via ScienceDaily.
Numerous techniques were utilized by the researchers.
These included examining the fungus' genome using RNA sequencing and conducting chemical analyses of odors released by the fungus and amplified in dead female flies.
In behavioral trials, male flies were exposed to deceased female flies that were at various stages of fungal infection as well as females who had died from other reasons.
This allowed researchers to study the male flies' sexual behaviors.
In this instance, research findings showed that male flies preferred mating with dead females who had fungal infections.
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Insect destroyer
When the lead researcher, Carolyn Elya, was a graduate student at the University of California, Berkeley in 2015, she was luring wild fruit flies with a lovely, decaying watermelon when she discovered the fungus, which is Greek for "bug destroyer," as per the National Geographic.
This is the first investigation of the puppet-master fungus, which has been investigated in house flies since 1855.
The fungus first feeds on the fly's hemolymph, which is the equivalent of blood in invertebrates, before moving on to the fat cells of the insect.
Free liposuction is followed by the start of mind control.
According to Elya, the fungus causes the fly to "crawl up anything nearby" and extend its proboscis before it dies.
The fly then drools something onto the area it is standing on that is probably a fungal secretion; this sticky material sticks the poor insect to the floor.
The fly is then subjected to a form of mind control by the fungus, which causes it to lift its wings erect until they are pushed out from their backs at a sharp upward angle, according to Elya.
A few hours later, a striped pattern created by the white fungus spreading out through the bug's brownish body may be observed.
In a stunning demonstration of physics, spores develop at the ends of the fungal fuzz and then shoot out of the fly's body like bullets, searching for another fly to infect.
According to Elya, the spore has the ability to go further than, for example, if the fly died on the ground because of the insect's height, elevated wings that keep the road free, and the forceful (20 mph) ejection of the spores.
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