Parasitic Worms Manipulate Mantises into Diving into Water, and we Now Know-how

Throughout nature, there are wonderful examples of parasites manipulating their hosts to change their behavior for their own benefit. There are species of fungi that ants climb trees from before they explode from their heads, snatch season during mating and their hips fall off, and unicellular parasites that sexually attract cats to urinate.

Researchers have now discovered how a parasite called the hair follicle hosts their prayer ministers and leaps into the water. Takua Sato, an associate professor at Kobe University in Japan, said, “I was originally an ecologist and found that infected hosts that jumped into the water became a very important source of seasonal energy for aquatic predators (salmonid fish) in Japan’s forests.” IFLScience is an associate professor at the university.

Parasitic Worms Manipulate Mantises into Diving into Water, and we Now Know-how

“A great example of how parasites (which are easily overlooked in ecological studies) are important in mediating ecosystem processes.” Begin their life in rivers and ponds, where their larvae enter the bodies of aquatic insects. These insects then spread their wings and emerge from the water, where predators, such as the praying mantis, wait. If an infected insect eats a mantis, the hair worms continue to grow and mature in its body. However, on the way back to the water to reproduce, the parasites need to be creative, manipulating their hosts to keep them submerged.

Scientists haven’t figured out how the parasite goes about this for a century, but new research published in Current Biology claims it’s cracked. It was previously thought that the brightness of the light flying from the water caused greed in mantids and other hairy insect hosts – but this explanation does not account for other bright spots that do not attract hosts. “Previous research has shown that positive photo taxis found in hair-infected cricket are a key factor in triggering water-logging behavior.

But as a field biologist, I don’t understand why we’ve never seen hair worms like burns like shallow, bright water,” Sato told IFLScience. Instead, the researchers estimated that the attraction is less than the polarization of reflected light.