Safety in numbers: The reason running water makes you want to urinate

An evolutionary adaptation

Photo by Andre Morales Kalamar on Unsplash

There are a few theories on the all-important question of why the sound of running water makes you want to urinate. The most popular being a Pavlovian response to the sound of past urination sessions.

I offer a deeper hypothesis born of evolutionary adaptation:

The sound of running water mimics the sound of other human beings urinating in your proximity, and that can be taken as a sign that it is safe to urinate here and now.

The reasoning behind this hypothesis is as follows:

Picture the primitive communities in which we all spent a vast portion of our evolutionary history as modern/proto-human beings.

1. Urination/waste disposal must be done some distance from the protection of the community for hygiene reasons. You are also somewhat incapacitated during the process.
2. This makes urination inherently dangerous (if you stray too far from the fire you might get taken out by a big cat). You should therefore scan the area carefully before giving yourself the all-clear.
3. By urinating together, in groups of 2 or more, it becomes far less risky (you bring with you the protection of the community). You have the eyes and ears of your fellow tribesmen as well as your own.
4. If you can hear someone else urinating, you can safely assume they have checked their surroundings and determined that the coast is clear.
5. If it’s safe enough for them to urinate safely, and you’re close enough to hear it, there’s a good chance it’s safe enough for you to urinate safely too.
6. Those of us with the caution to urinate in groups were less likely to be taken out by a red-toothed predator and subsequently more likely to propagate our genes.
7. Thus evolved over time, the physiological prompt to relax and urinate when you hear the sound of others urinating — interchangeable with the sound of running water.

Naturally, this hypothesis is highly speculative with no supportive evidence — but my gut tells me I’m onto something here.

Thanks for reading, and please comment if you have any evidence that contradicts the above hypothesis.

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