Monica Gagliano and Thus Spoke the Plant
Monica Gagliano (b. 1974) is an Italian-Australian evolutionary ecologist whose pioneering research explores plant behavior, cognition, and communication. Trained in marine ecology, Gagliano is best known for experimental studies demonstrating that plants can learn, remember, and respond to their environments in ways once believed exclusive to animals.
Raised in Italy, Gagliano received her PhD in marine ecology from James Cook University in Australia and launched a successful academic career studying coral reef fish. But a crisis of conscience—brought on by experiments that required her to kill sentient sea creatures—led her to leave the field. This rupture prompted a journey to the Peruvian Amazon, where she apprenticed with Indigenous healers and worked with plant medicines including tobacco, ayahuma, and ayahuasca in ceremonial contexts. There, she began to hear plants speak. These visionary encounters would alter the trajectory of her life and research.
In the years that followed, Gagliano helped establish the field of plant bioacoustics and argued, provocatively, that plants should be treated not merely as objects of study but as subjects—interlocutors in scientific dialogue. What distinguishes Gagliano’s work is not only its empirical findings but the method through which they arose: visionary episodes in which plants imparted instructions that shaped her experimental design. These experiences are chronicled in her memoir Thus Spoke the Plant: A Remarkable Journey of Groundbreaking Scientific Discoveries and Personal Encounters with Plants (2018), a genre-defying text that blends autobiography, ethnobotany, and vegetal revelation.
In the book, Gagliano recounts how dreams, altered states of consciousness, and ceremonial encounters guided her research, even when doing it meant risking professional marginalization. Structured as a series of dialogues with individual plants, the book presents each plant as a distinct being—wise, idiosyncratic, and articulate. Gagliano describes the book as written “about plants and by plants,” and claims those plants helped her enact a “new formulation of contemporary science,” one that operates at the frontier “where the physical world and alternate domains of reality (weirder than we can conceive of) meet.”1
In the visionary episodes below, an oak tree reveals Gagliano’s life’s mission: to “tell our stories” and serve as a scientific medium for plant beings. In another, the Amazonian plant ayahuma dictates the design of one of Gagliano’s most controversial and impactful experiments, which demonstrated associative learning in pea plants.
Today, Gagliano holds a research position at Southern Cross University in Australia. Her work has shaped emerging fields in philosophy, literature, and the arts, in addition to plant biology. Despite fierce criticism from some in the scientific establishment, Gagliano’s writings have helped expand our understanding of intelligence, communication, and consciousness beyond the human. Her work has not only altered the field of plant science but also challenged foundational assumptions about what counts as valid ways of studying and being in relationship with more-than-human beings.
Source
The following episode occurred while Gagliano was on a vision quest to which she had been invited by a Lakota healer. The quest took place at a time of great stress, shortly after Gagliano had submitted a grant proposal to the Australian Research Council to study sound communication in plants—a decision met with scorn among colleagues, some of whom characterized the move as “career suicide.”2 For this quest, Gagliano was stationed alone on a mountain, without food or water, for four days.3
At the top of the mountain . . . I was no longer aware of how many days I had been there or how much time I had left before having to come down. A sense of anxiety started creeping in . . . . Would my prayer be answered? . . .
I was bearing witness to my own undoing when the oak tree spoke. “Tell our stories,” he stated with authority. Startled, I looked up toward the old tree. He reiterated, “You are here to tell our stories.” And the conversation began. If I had had pen and paper (which, of course, I did not), I could have written down a list of all the things that, according to the tree, I was here to do. I was fumbling around inside my mind, as he, endlessly calm and steady, went on emphasizing how important my scientific work was as a medium for plant people. I would tell their stories, which would reveal them—plant people—to the human mind, and in doing so, deliver something humanity urgently needed. . . .
You need not worry about the boring details [how to make money and have a secure job]. We are well aware of your needs, and every single one of them has already been taken care of.
The next episode occurred after some days apprenticing to an Indigenous shaman—Gagliano calls him Don J—in the Peruvian Amazon. Gagliano recounts how the ayahuma plant dictated the design of one of her most groundbreaking experiments.4
As Don J had mentioned the day before, while looking at the plants growing around his hut, the plant spirits themselves teach us what to do . . . by showing me this strange fruit that looked like a cannonball, Piñon blanco had told me the plant that was waiting to work with me next. And ready she was, the mighty Ayahuma.
“The experiment is pretty simple. Train young plants in a maze and give them the freedom of choice,” Ayahuma declared, inside myself. Then she added, “But you’ve got to think peas, not sunflowers.” For several months earlier that year, I had tried to design an experiment that would allow me to test plants’ ability for associative learning . . . how to actually test this in plants was something that I had stubbornly been thinking about since 2011 . . .
Ayahuma is widely recognized as a mighty protector and teacher. Although this tree is typically considered a powerful maestro . . . the spirit often also appears as a giant woman and, specifically, one without a head. I never actually glimpsed at her ethereal form—but this wonderfully quirky and buoyant spirit enjoyed playing with my head (in the most benevolent ways!) and educating my mind. To do so, she made sure I could hear her voice loud and clear when she started prescribing the complete set of instructions for testing Pavlovian learning in plants. I transcribed as she dictated. . . . As instructed by Ayahuma, I set up a series of experiments by placing pea seedlings in individual Y-shaped mazes constructed out of PVC pipes.
Bibliography
Bridle, James. Ways of Being: Animals, Plants, Machines: The Search for a Planetary Intelligence. New York: Farrar, Straus and Giroux, 2022.
Gagliano, Monica. Thus Spoke the Plant: A Remarkable Journey of Groundbreaking Scientific Discoveries and Personal Encounters with Plants. Berkeley: North Atlantic Books, 2018.
———. “In a Green Frame of Mind: Perspectives on the Behavioural Ecology and Cognitive Nature of Plants.” AoB PLANTS 7 (2015): plu075.
Gagliano, Monica, Mavra Grimonprez, Martial Depczynski, and Michael Renton. “Tuned In: Plant Roots Use Sound to Locate Water.” Oecologia 184, no. 1 (2017): 151–60.
Gagliano, Monica, Michael Renton, Nili Duvdevani, Matthew Timmins, and Stefano Mancuso. “Out of Sight but Not out of Mind: Alternative Means of Communication in Plants.” PLoS ONE 7, no. 5 (2012): e37382.
Gagliano, Monica, Stefano Mancuso, and Daniel Robert. “Towards Understanding Plant Bioacoustics.” Trends in Plant Science 17, no. 6 (2012): 323–25.
Gagliano, Monica, Vladyslav V. Vyazovskiy, Alexander A. Borbély, Mavra Grimonprez, and Martial Depczynski. “Learning by Association in Plants.” Scientific Reports 6 (2016), 38427.
Gagliano, Monica, John C. Ryan, and Patrícia Vieira, eds. The Language of Plants: Science, Philosophy, Literature. University of Minnesota Press, 2017.
Ryan, John C., Patrícia Vieira, and Monica Gagliano, eds. The Mind of Plants: Narratives of Vegetal Intelligence. Santa Fe, NM: Synergetic Press, 2021.
Pollan, Michael. “The Intelligent Plant.” The New Yorker, December 15, 2013. https://www.newyorker.com/magazine/2013/12/23/the-intelligent-plant.
Shechet, Ellie. “Do Plants Have Something to Say?” The New York Times, August 26, 2019. https://www.nytimes.com/2019/08/26/style/can-plants-talk.html.
Rachael Petersen
Rachael Petersen studies the interplay of philosophy, science, and literature in the long nineteenth century, with a particular focus on how German thinkers engaged questions of mind, matter, and animacy across human and nonhuman life. Her work traces how developments in biology and psychology shaped metaphysical and political thought, examining figures such as Gustav Fechner, Ernst Haeckel, and others. Rachael holds a Bachelors from Rice University and a Master of Divinity from Harvard, where she was awarded the Esther Sellholm Walz Prize for her thesis on Fechner’s Nanna: Oder Über das Seelenleben der Pflanzen. At the Center for Study of World Religions, she launched and led the Thinking with Plants and Fungi Initiative, convening interdisciplinary public programs that explored vegetal and fungal life in relation to questions of sentience, cognition, and care.
Prior to her doctoral studies, Rachael spent a decade working at the intersection of conservation, science policy, and environmental advocacy, consulting for nonprofits and philanthropies worldwide. She has conducted fieldwork in the Amazon, Borneo, and Arctic Canada, and previously served as Senior Advisor to the National Geographic Society and Deputy Director of Global Forest Watch. Rachael is also a creative writer and poet, with work appearing in The Sun, Aeon, Harvard Divinity Bulletin, Tricycle and elsewhere. In addition to German, she speaks Spanish and Portuguese. You can learn more about Rachael at rachaelnpetersen.com.
