The study was conducted in the laboratories of Prof. Yossi Yovel from the School of Zoology and Prof. Lilach Hadany from the School of Plant Sciences and Food Security at TAU's Wise Faculty of Life Sciences. It was led by students Dr. Rya Seltzer and Guy Zer Eshel, in collaboration with scientists from the Plant Protection Institute at the Volcani Institute. The paper was published in the journal eLife.

This study follows the dramatic discovery published by the same researchers about two years ago, which generated worldwide interest: plants under stress emit sounds—at ultrasonic frequencies, above the range of human hearing, but detectable by many animals. The researchers state: “That discovery opened the door to extensive research on acoustic communication between plants and animals. In the present study, we began to explore this subject.”

Prof. Yovel explains: “After proving in the previous study that plants produce sounds, we hypothesized that animals capable of hearing these high-frequency sounds may respond to them and make decisions accordingly. Specifically, we know that many insects, which have diverse interactions with the plant world, can perceive plant sounds. We wanted to investigate whether such insects actually detect and respond to these sounds.”

Prof. Hadany adds: “We chose to focus on female moths, which typically lay their eggs on plants so that the larvae can feed on them once hatched. We assumed the females seek an optimal site to lay their eggs — a healthy plant that can properly nourish the larvae. Thus, when the plant signals that it is dehydrated and under stress would the moths heed the warning and avoid laying eggs on it? To explore this question, we conducted several experiments would the moths heed the warning and avoid laying eggs on it? To explore this question, we conducted several experiments.”

Prof. Yossi Yovel and Prof. Lilach Hadany

In the first experiment, aiming to isolate the auditory component from other plant features like color and scent, the researchers presented the female moths with two boxes: one contained a speaker playing recordings of tomato plants in a state of dehydration, while the other was silent. The moths showed a clear preference for the ‘noisy’ box, which they likely interpreted as a living plant (even if under stress). Conclusion: the moths do indeed perceive and respond to a playback of plant-emitted sounds. When the researchers neutralized the moths’ hearing organs, this preference disappeared and they chose both boxes equally — clear evidence that the preference was specifically based on listening to sounds, and not on other stimuli.

In the second experiment, the female moths were presented with two healthy tomato plants – one with a speaker playing sounds of a drying plant, and one that was silent. Again, they showed a clear preference – but this time for the silent plant, from which no distress sounds were heard, and therefore probably serves as a better site for laying eggs.

In another experiment, the moths again faced two boxes—one silent and the other containing male moths, which also emit ultrasonic sounds at a frequency similar to plant sounds. This time, the females showed no preference and laid their eggs equally on both boxes. The researchers concluded that when deciding where to lay their eggs, the females specifically respond to plant-emitted sounds — and not, for example, to sounds made by males.

The researchers conclude: “In this study, we revealed the first evidence for acoustic interaction between a plant and an insect. We are convinced, however, that this is just the beginning. Acoustic interaction between plants and animals doubtlessly has many more forms and a wide range of roles. This is a vast, unexplored field — an entire world waiting to be discovered.”

The program's initiator, Prof. Dalit Rom-Shiloni from the Department of Biblical Studies, Chaim Rosenberg School of Jewish Studies and Archaeology, explains: "The Orit of Beta Israel includes the Five Books of the Torah, as well as the Books of Joshua, Judges, and Ruth. So far, we have documented four Orit books, including the two from the 15th century, as well as 13 other sacred books. All the sacred books of Ethiopian Jewry are written in Ge'ez, a language known only to the Kessim, and each manuscript has its own fascinating story. They have been passed down through generations from father to son, and some were given to Kessim by their teachers — Jewish monks who taught the sacred traditions in Ethiopia. The books were carefully guarded and preserved, with some of their owners even risking their lives to bring them to Israel. Today, most of these books are privately owned by Kessim and their families and used as “living books” in the prayer houses of Ethiopian Jewish communities across Israel. Until now, they were inaccessible to interested individuals of the general public, nor to the research world, and we intend to locate as many books as possible for preservation, digitization, and academic study."

To this end, a unique traveling workshop was held in June 2024, with participants including: Prof. Rom-Shiloni, anthropologist Prof. Erica Weiss, linguist Dr. Anbessa Teferra, and students from the Orit Guardians program — all from Tel Aviv University, alongside representatives of the Ethiopian Jewry Heritage Center and the National Library, as well as three international experts in ancient Ethiopian sacred texts: Prof. Loren Stuckenbruck (Ludwig Maximilian University of Münich), Dr. Sophia Dege-Müller and Ted Erho (University of Hamburg). The international experts examined and dated the books using palaeography — based on script forms. To their astonishment, they found that two of the Orit books were written as early as the 15th century — the oldest discovered so far in the hands of Beta Israel. Prof. Rom-Shiloni explains: "Our discovery is causing a stir among experts in the field worldwide. While we are familiar with similar Ethiopian texts from this period or even earlier, all of those are Christian texts, not Jewish. Now, for the first time, it has been revealed that Kessim from Beta Israel possess Orit books that are over 600 years old."

In total, the workshop yielded four Orit books — two from the 15th century and two from the 18th century, as well as 13 other sacred books from the 17th to 20th centuries. All the discovered books were documented with their owners’ consent and remain in their possession — so they can continue to serve as “living books” in their communities. The documentation now enables academic research and the establishment of a digital archive at the National Library.

Prof. Youval Rotman, Academic Director of the Koret Center and faculty member in the Department of Jewish History at Tel Aviv University, added: "This is an extraordinary finding. Discovering ancient manuscripts is rare, and when they are the oldest of their kind in existence, the find is all the more exceptional. This discovery was made thanks to the Orit Guardians' emphasis on studying the textual knowledge and interpretive tradition preserved and orally transmitted over centuries within the various Beta Israel communities. The uniqueness of the program lies not only in mapping manuscripts and training students for their research but also in doing so as an integral part of the knowledge preserved within the community — thereby continuing and expanding it. The young researchers form personal connections and earn the trust of the Kessim as successors to the tradition and oral interpretation. In doing so, they connect communal-social knowledge to academic knowledge — and this is our great pride. The program unearths hidden treasures that have so far dwelt within the four walls of local synagogues, then documents and studies them and makes them accessible. Imagine a situation in which the great Bible commentaries were passed down orally through generations."

Prof. Rom-Shiloni concludes: "Through the traveling workshop of the Orit Guardians program we discovered 17 sacred books of Beta Israel held by Kessim across Israel and still used as “living books” in the prayer houses of Ethiopian Jewry. Among them, we discovered two Orit books — the Torah of Beta Israel — written in the 15th century, the earliest found so far in the hands of Jewish Kessim.
Alongside the excitement, we believe our discovery is only the tip of the iceberg. It is likely that many more sacred books of Beta Israel are held by families and Kessim around the country, and we will continue searching for them. It is important to emphasize that all manuscripts located (like those found through the workshop) will remain in the possession of their owners, while being photographed and documented to make them accessible to interested members of the community, the broader public, and researchers in Israel and around the world. Another, especially urgent task of the Orit Guardians is documenting the scholarly oral traditions of the Kessim in Ethiopia, which includes translation from Ge’ez to Amharic and interpretation of the Orit and other holy books. This heritage, transmitted only orally from generation to generation, has never been set down in writing. Today, only 18 senior Kessim, who were trained in Ethiopia and hold this knowledge, remain active in Israel, and they are aging. If we do not act quickly, we might lose this precious cultural treasure."