Is a Spider’s Web Part of its Brain?

With the help of their webs, spiders are capable of planning, learning, and other complex cognitive tasks, challenging our ideas of intelligence.

Earlier this year, biologist David Robson published an essay explaining a new extraordinary king of consciousness. A consciousness found in spiders that allows their minds to extend beyond their bodies.

Spiders are basically blind, and rely on vibrations that ripple through their webs to interact with the world. Sitting at the hub of their webs, spiders pull gently on the threats to adjust how sensitive they are to these vibrations in different parts of the webs. And it works. When insects land on the tensed areas of webs, spiders are more likely to notice and capture them. And when spiders are gunfire, they tighten the radial threads, hoping to detect even the smallest prey.

When a spider sits at the hub of its web, it isn’t just passively waiting for vibrations. It is actively tugging and loosening different strands, manipulating the web in subtle ways.In this way, the tension of the web is a type of filter. The spider and web work together as a larger cognitive system in which changes in the spider’s cognitive state alter the web and vice versa.

Spiders also learn over time. If one section of the web catches more prey, the spider will likely enlarge that part in the future.

Further, the state of the spider’s nervous system can affect its webs. In the 1940’s researchers gave spiders caffeine, amphetamines, LSD, and other drugs. When dosed, spiders created irregular strange webs.

There is an ongoing debate about whether or not this constitutes extended cognition. Webs evolved over time into an extension of the spider’s body and sensory system, but does that mean it’s part of the mind?

It’s part of a theory of mind known as “extended cognition,” and humans utilize it too. For instance, we might like to think of our minds as contained in our heads, but we rely on a number of structures outside of our heads (and even outside of our bodies) to help us think. Computers and calculators are an obvious example. We organize our living spaces to help us remember where things are, we jot notes, and we take photographs or store mementos.

Spiders both passively receive information from their webs and actively manipulate how that information gets back to them by making adjustments.

This leaves the philosophical question to be answers about whether spiders use webs to form mental representations and, further, if this constitutes “consciousness.”

Even so, I think we can still learn something about ourselves from these spiders. All those interconnected threads are necessary and support each other in doing the web’s job. Similarly, our own brains do not operate in isolation. At the same time that we are using working memory, we are also using visual processing, and auditory processing. Our brains are deciding what to pay attention to, what to just handle subconsciously and what you to need to be consciously working with – a neural web.

So, take a moment to marvel at the incredible and fascinating construction that is a spider web before simply dusting it away. And thank you to the researchers continuing to pursue these questions!