The gray-green fronds of a neglected staghorn fern drooped sadly down the sides of its pot, which was full of desert-dry soil. I wasn’t sure it had a chance at revival, but I wanted to try. I researched its needs, watered it, and placed it in a south-facing windowsill. A few months later, bright green fronds unfurled from its center, reaching straight up in full vitality. As a naturalist and nature-lover, I beamed with joy at having succeeded in bringing this plant back to life.
This delight is rooted in biophilia: humans’ innate love of living things. E.O. Wilson’s 1984 book Biophilia popularized the term in the cultural lexicon, and innumerable anecdotal accounts of the phenomenon support its existence, despite the lack of quantitative proof that we have some hardwired love for nature. Naturalists, it would seem, are the equivalent of a type-specimen for biophilia. I can recall so many moments of experiencing it in my life: flipping logs to find toads as a child in Florida, the salmon run in Alaska, my first hike through California’s old growth redwoods. The wonder and awe were already within me.
I recently stumbled upon a study that has made me rethink my understanding of the term. In 2022, scientists from the University of Chicago designed a wrist-worn heart rate monitor that only works if a slime mold – integrated into its electronics – is properly nourished by the wearer. The study was investigating whether humans might develop a “care-based relationship” with the device if its function depended on an actual living organism. The slime mold is housed in a transparent case at the base of the device and integrated with the circuitry of the heart rate monitor. Users feed the slime mold by placing watery oats in a compartment on the side of the case. If left unfed for too long, the slime mold goes dormant, and the device stops working. The results of the study suggest that, yes, users do indeed care for the slime mold and the device, and therefore are likely to keep the device for longer.
Slime molds are in the kingdom Protista – a catch-all kingdom for eukaryotic organisms that are not plants, animals, or fungi. The species used in the study, Physarum polycephalum, might be familiar to you as the slime mold that, in a famous experiment, recreated the routes of the Tokyo metro system when presented with food arranged in the pattern of the actual stations. Despite being single-celled, it demonstrates incredible problem-solving abilities and social dynamics. In a group known as the plasmodial slime molds (class Myxomycetes), Physarum polycephalum goes by the common name “the blob,” which refers to the bright yellow oozing appearance of the organism as it feeds on microbes and decaying organic matter. It’s hardly an adorable creature.
The human capacity for biophilia is, apparently, so great that a single-celled yellow blob, completely isolated from its forest habitat, enabled caring relationships between people and heart rate monitors. Study participants called the device their “little friend” and “pet,” and all participants described feeling “sadness” when they were instructed to neglect the slime mold as part of the study. As a naturalist, I can understand biophilia for shrews, grassland hybrids, or even individual staghorn ferns. It blows my mind that a slime mold can have the same effect.
Perhaps this study’s revelations on the reach of biophilia can help build a more engaged and understanding conservation community. Can naturalists help people access their own biophilia to reduce bear-human conflicts, or to save mudpuppies from death by lampricide? Can we go a step further, and harness biophilia to nudge people toward a better understanding of our collective reliance on biodiversity? Simply going outside and being face to face with the plants, animals, and slime molds of our local trails might be even more impactful than previously thought, if we allow ourselves the time to develop relationships with them. If the presence of a slime mold can convince people to care for a plastic watch, then I am convinced that biophilia can be better leveraged to grow the conservation community.
