The family Araneidae includes more than 3,000 species of spiders, widespread throughout the world and known for building webs with the most classic shape possible, the spiral ones. Some of these species decorate their webs with what they call themselves establishes – agglomerations of silk and other materials that are placed in specific places for the most disparate purposes.
Do you want an example? A study published in Ecology and Evolution tells of two species of the genus Cyclosa who, to keep predators away from their web, decorate it with “puppets”, simulacra of large spiders that scare and disorientate birds, lizards and other potential dangers.
The spider monument. We wrote “two species” but in reality, reading the study, it turns out that there are three: Cyclosa inca And Cyclosa longicauda live in Peru, while the species of Cyclosa observed in the Philippines, and which uses the same technique as its South American relatives, has not yet been identified, because it was only observed “from afar”, and it has not been possible to capture a specimen. All three species, however, are small in size (2.5 mm), but build webs of more than respectable, as well as frightening, dimensions.
The strategy of the three spiders is identical: they collect various debris (pieces of leaves, twigs, the corpses of their prey…) and mix them with the silk they use to build the web. The material obtained is then shaped into the shape of… a giant spider, much larger than its creator and with an unmistakable eight-legged silhouette.
Multipurpose puppet. The gigantic (relatively…) simulacra are therefore not a simple decoration, but have a defensive purpose: not only do they keep the natural predators of the spiders at a distance, but they also serve as a real hiding place, given that the specimens of Cyclosa they are the same color as their “scarecrows” – which therefore also serve as bunkers. But also from the control room: when a predator approaches, the hidden spiders shake their abdomen, producing vibrations that make the puppet seem alive.
On the run. However, it must be said that these spiders also know when to run away: during field observations, the researchers noticed that, when they got too close to the web, the Cyclosa they threw themselves on the ground in search of a safer hiding place, returning to the canvas only once the danger had passed. Finally, there is one last use worth mentioning for the spider puppet: i Cyclosa they use it when they have to move the newly laid eggs to a new nest, hiding them inside the mass of silk and debris.
