Some Spiders Are Evolving to Be More Social — And Scientists Say That Could Mean They’re Growing More Intelligent

Most spiders are lone hunters, which means that they live and hunt for food by themselves. This is mainly because of the evolutionary adaptation that naturally selected solitary spiders. They rely on staying still and camouflaging to ambush prey, and being with a group can disrupt this rhythm, making survival harder.

Spiders are also territorial, and being social means more competition that could lead to cannibalism. However, a growing number of species are evolving social behavior, living and hunting together in colonies. Now, being more social also meant an increase in cognition and brain capability, one of the drivers of how humans evolved to be the smartest creature on the planet.

The Rise of Social Spiders

Social spiders are still very rare, with only about 23 known species out of 45,000+. These spiders build massive webs to catch more prey to feed everyone in the group. Unlike most spider species, social ones create interconnected webs shared by hundreds or thousands of individuals.

Species like Mallos gregalis, could catch much bigger prey with their collective webs, which is far larger than any solitary spider species could catch. This shift is not just a mutation in a population; it is a unique evolutionary lineage that clearly works in select ecological environments.

Read more: Wikipedia | Australian National University

Bigger Brains or Smarter Brains?

Social Spiders & Communal Tarantulas w/ Dr. Linda Rayor

Researchers at the Australian National University found that social species such as huntsman and African social spiders can show a more refined nervous system than solitary spider species. However, there are also some study that goes deeper into what regions of their brains changed.

Scientists found out that due to task task-sharing feature of communal spiders, they had reduced volume in certain brain areas, while brain regions tied to communication and coordination improved. The reallocation of the brain size and power of social spiders is directly correlated to their focus on group communication, cooperation, and nest maintenance.

Spiders with Memory and Insight

Scientists also argue that spiders are more intelligent than they are given credit for. They know how to avoid prey that could pose a danger to their life, return to the same place where they catch a meal, and even adjust their web-building strategies based on experience on what works or not.

This means that they have spatial memory, the ability to learn, and gather feedback from their environment, whether they are solitary or social. However, the social brain theory that the more species cooperate, the more complex their nervous system does, could maybe apply to some species of spiders too.

Read more: IFLScience

Sociality as a Driver of Intelligence?

In mammals and birds, there is a social brain theory that states that complex social and community systems could drive brain evolution, and some spiders might be capable of this feature, too.

Since members of social spiders share tasks, they become repetitive and are easily memorized, but they also share a lot more information because of the need to coordinate in order to build larger webs that could improve prey capture.

Studies have also shown that during storms or other existential threats, communal spiders behave similarly and respond collectively, which is another indication of the sharing of information. All of this could result in the same evolutionary event, which furthers the cognitive abilities of mammals and birds.

The Insane Evolution of Spiders

Author's Final Thoughts

The evolution of social behaviors and communities played a big role in the evolution of humans and their brains. While differing in complexity, intricate social structures, cooperation when gathering food and maintaining a nest, and stronger social bonds are some similarities between social spiders and humans, along with other mammals and birds.

As we examine more about how humans evolved to be who they are today, spiders might offer an unexpected window to gather insights into how brains evolve in community-driven environments.

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