A team of scientists in Japan have discovered how a particular species of wasp uses natural secretions from its body to force larger spiders to build it a home only to have the unsuspecting arachnids killed after the labor is done.
In a study featured in the Journal of Experimental Biology, Kobe University researcher Keizo Takasuka and his colleagues gathered specimens of a species of spider known as Cyclosa argenteoalba. These arachnids were located in different shrines around the cities of Sasayama and Tamba.
Upon closer examination of the spider specimens, the researchers found that some of the insects have been previously parasitized by a wasp known as Reclinervellus nielseni. This was done by laying the wasp eggs either on the spiders or within their body.
Takasuka and his team noticed that each of the parasitized spiders was suddenly compelled to produce webbing, complete with a cocoon and decorations of web using their silk. The spiders worked on this web for approximately 10 hours, and it was finished just in time before the larvae of the wasp begin to pupate.
The spiders used several strands of fibers to produce the web, making it up to 40 times stronger and more durable compared to the usual webbing that the arachnids create for their own habitat as well as for catching their prey.
Once they finish building the special web, the larvae of the wasp would move into the new habitat and begin its process of becoming a pupa using the silk cocoon. The wasp pupa would then lure the hapless spider toward it and kill it.
According to the researchers, the substance that the wasp injects into its spider victim is made of a hormone compound, similar to the one that is naturally-produced by the spiders themselves. Takasuka and his colleagues believe that this manipulative compound causes a chemical reaction from within the endocrine system of the spiders, resulting in their unusual and hyperactive behavior of web-building.
This manipulative behavior is also seen in other parasitic organisms that often take advantage of their hosts for their own benefit.
One such organism is the horse worm which is typically seen developing in the bodies of grasshoppers and crickets. This species of worm manipulates the actions of its host, forcing the larger insects to jump into streams to allow the adult worm to emerge and go off on its own. This resulting worm would then repeat the whole process to produce more of its kind.