In a cave located on the border between Albania y Greecescientists documented a giant spider web of more than 106 meters squares inhabited by around 110.000 spidersin what is already considered one of the most surprising findings in recent underground biology.
The most striking thing is not only the size of the structure, but that it is made up of Tegenaria domestica y Prinerigone vagans, two species that normally live alone. In this case, both developed a stable coexistence within the same giant network, something never before documented in these animals.
The discovery was studied by international teams and published in the scientific journal Subterranean Biologywhich describes a complex underground ecosystem supported by bacteria that oxidize sulfur, the basis of the entire food chain of the place.
What is the gigantic colony of spiders like in a cave without light
The structure is located within the call Sulfur Cavea cavity with an atmosphere rich in hydrogen sulfide and stable temperature close to 26 °C. No sunlight reaches there, so life depends on chemical processes instead of photosynthesis.
In one of the hallways near the entrance, the researchers detected a network made up of thousands of individual spider webs connected to each other. The complex covers more than 100 square meters, a surface area comparable to half a tennis court.
Within this gigantic network, approximately 69,000 specimens coexist that belong to the species Tegenaria domestica, while 42,000 correspond to the arachnid species Prinerigone vagans.
The phenomenon was first observed in 2022 by cavers and then analyzed in detail by multidisciplinary teams.
How two solitary species that learned to coexist without aggression
Under normal conditions, these spiders do not share territory. In fact, one could prey on the other. However, in the extreme environment of the cave they coexist without aggression and form a stable cooperative structure.
Scientists believe that this coexistence is explained by the total darkness of the cave, which reduces visual perception among predators; in addition, the abundance of food reduces competition and, finally, the extreme environment favors unusual adaptive behaviors.
This case represents the first documented record of two solitary species forming a shared supercolony of this magnitude.
How spiders survive without sunlight
in the cave there is no photosynthesis. The base of the food chain is chemosynthesisa process in which bacteria obtain energy from sulfur present in the environment.
The system works as follows:
- Sulfur-oxidizing bacteria produce organic matter.
- That matter feeds larvae of small insects.
- The adult insects become trapped in the spider web.
- Spiders feed on them.
It is estimated that More than 2.4 million non-biting mosquitoes live in the cavewhich guarantees enough food to keep the colony stable.
Most of Spiders are solitary animals. The construction of permanent collective networks is extremely rare, especially in caves.
In this case, the structure is not a single continuous spider web, but a mosaic of individual funnels connected to each other. This organization allows us to capture more prey, reduce risks from predators, and make better use of the available space.
The researchers consider that this cooperative behavior could be driven by the constant availability of resources in the underground ecosystem.
