Spiders, unlike ants or bees, do not have queens because the vast majority of the over 50,000 known spider species are solitary creatures. While the solitary nature of spiders is the biological default, a small number of species have evolved unique forms of communal living. However, even these group-living spiders lack the specialized reproductive structure that defines a true queen found in highly organized insect societies.
Solitary Spiders: The Standard Model
The default behavior for nearly all spiders is one of aggressive independence, focused on individual survival and reproduction. Most species, such as orb-weavers or wolf spiders, operate in isolation, building their own webs and hunting alone. This solitary existence is reinforced by a high degree of intraspecific aggression, meaning adult spiders frequently attack and consume others of their own species.
Hunting and web construction are individual tasks, and cooperation is generally limited to the brief period of mating. Female spiders often exhibit maternal care, guarding an egg sac and sometimes feeding spiderlings. However, this care is short-lived, with the young dispersing via walking or “ballooning” shortly after hatching to establish their own solitary lives.
What Defines a Social Insect Queen?
The idea of a “queen” is linked to eusociality, the highest level of animal social structure seen in ants, bees, wasps, and termites. This system is defined by three characteristics that allow the colony to function as a “superorganism”:
- A reproductive division of labor, where only the queen is capable of reproduction, giving her a reproductive monopoly over the colony.
- The existence of distinct, often sterile, worker castes that perform all necessary tasks like foraging, defense, and nest maintenance. These workers forego their own reproduction to support the queen’s offspring.
- Overlapping generations, meaning offspring remain in the nest to assist their parents in raising subsequent broods, leading to a continuous, self-sustaining society.
A queen’s pheromones often regulate the behavior and reproductive development of the worker caste, maintaining the rigid hierarchy.
Communal Living: Spiders That Share Webs
Although they do not have queens, a small fraction of spider species do live in groups, exhibiting varying degrees of sociality. These are often referred to as communal or quasi-social spiders, with the genus Anelosimus providing examples. Species like Anelosimus eximius construct massive, permanent communal webs that can house thousands of individuals.
Within these shared structures, the spiders coordinate activities such as cooperative prey capture, subduing insects much larger than any single spider could manage alone. They also engage in joint web maintenance and shared brood care, with multiple females contributing to the protection and feeding of the young. This group living strategy improves their collective survival and reproductive success.
Absence of Caste Systems and True Queens
Despite their cooperation, communal spiders fail to meet the biological criteria for having a queen, distinguishing them from true social insects. The most significant difference is the absence of a reproductive monopoly; almost all adult females in a communal spider colony are reproductively active. There is no single egg-laying sovereign or a female that suppresses the reproduction of others.
Communal spider societies also lack the specialized, sterile worker castes that define eusociality. While some spiders may perform certain tasks more often, any adult female retains the full capacity to reproduce. The social unit is often genetically inbred and can be relatively fragile, sometimes collapsing under environmental stress.