Meet my pet watch: Scientists create living smartwatch powered by slime

Luke Benedictus

It’s probably a sign of just how much some people care about their watches, but timepieces have long been attributed human characteristics. I’ve often heard the movement of a watch described as its “beating heart”, while it’s also routine to talk about a watch’s “face” or “hands”.  Perhaps this is a natural development given that a watch is an unusually intimate device that we wear day-in, day-out next to our skin. But a new creation from researchers from the University of Chicago has taken this anthropomorphic idea to a whole other level.

The researchers created a unique watch design in which the case is filled with an electrically conductive single-cell organism known as “slime mould”. The watches were designed to tell the time and measure the wearer’s heart rates. But that second function was dependent upon the health of the Physarum polycephalum, a species of slime mould apparently known for its rapid growth, resilience and curious maze-solving abilities.

The watch will only fully work when the organism is healthy, requiring the user to regularly feed it a mixture of water and oats to induce its growth. When the slime reaches the other side of the enclosure, it forms an electrical circuit that activates the heart-rate monitor function. When not fed, the organism enters a dormant state, although it can be revived at a later date.

“People were forced to think about their relationship to devices in a lot of really interesting ways,” said Jasmine Lu, who created the watch alongside Assistant Professor Pedro Lopes.

“When discussing their experiences with normal smartwatches, Fitbits, or other wearable devices, people said they just used it for an explicit purpose. And with this device, it felt more like a bi-directional relationship because they had to care for it. They also had some sort of attachment to it because it’s living, and they felt like they couldn’t throw it away, or just put it in the closet.”

Once the watches were built, Lu and Lopes conducted a study with five participants who wore the watch for two weeks. Over the first week, the users cared for the slime mould until the heart-rate monitoring was enabled. Then for the second week, the researchers asked participants to stop feeding the organism, causing it to dry out and disrupt the heart-rate function. Throughout the study, participants were asked to write in journals about their feelings regarding the device and answer interview questions.

Reviewing the responses, the researchers found a high level of attachment to the watch, with some users saying it felt like a pet – even naming it, or putting their partner in charge of the feeding when they got sick.  Some of the subjects also experienced pangs of guilt and grief when they were told not to feed the watch.

“People were shocked; almost all of them were like, ‘Really? I have to do that?’” Lopes said. “There were very human responses. Some people were sad, some people really felt like the connection was broken.”

Lu hopes that her research will inspire designers to create technologies that inspire deep attachment, thereby making devices that feel less disposable.

Bringing to life a watch that provokes such emotional attachment is certainly a development that would seem to merit further exploration from the industry. Although should this technology ever be taken up by the watch world, expect to hear the term “slime mould” replaced for something with a slightly more aspirational ring to it.