Crickets chirp, fireflies glow and both follow a surprisingly similar rhythm. A new study shows that communication resonates throughout the animal realm at a rhythm that is also familiar to our brains.
Researchers recently observed a remarkable phenomenon during a warm evening in Thailand. Crickets were chirping. Fireflies were emitting their light signals. Different species, different senses, different evolutionary histories. But their signals seemed to exhibit surprisingly similar rhythms of about 2.4 Hz—roughly corresponding to the pace of a brisk walk. Did this surprising degree of synchronization indicate a deeper connection?
These initial observations led the researchers to a remarkable insight: “Across 8 orders of magnitude in body weight, across modalities (vision versus audition), and across the tree of life (insects, including fireflies and crickets; crustaceans; amphibians; birds; fish; and mammals, including apes, humans, and sea lions), communicating at a ‘carrier frequency’ of ~0.5–4 Hz seems to be the norm. The instances we found are widespread—they come from all around the world and occur in creatures from the air, land, and sea.”1
The Neurological Significance of This Frequency Range
The so-called delta wave range is often regarded as a “sweet spot” in animals, a kind of “comfort zone” for the nervous system. It typically occurs during deep sleep, when motor activity is reduced, or during periods of withdrawal from external activity. In most vertebrates, it is considered a hallmark of the bodily regeneration processes that take place during sleep. To describe the brain’s shift toward this preferred range, researchers use various concepts, each highlighting different mechanisms: entrainment, tuning, synchronization, or resonance. Many researchers, for example, believe that animals are biologically tuned to process communicative signals in this frequency range especially efficiently.
Ultimately, the authors hoped that identifying a shared neural “comfort zone” might help deepen our understanding of animal behavior and, at the same time, explain why human language, speech, movement, and music exhibit similar rhythms. The surprise at this cross-species communication—the light of the firefly and the sound of the cricket—also makes us more receptive to the mystery of communication itself, a mystery that has preoccupied philosophers from Plato to Buber.
The Power of Entrainment
From the consciousness-altering lullaby that gently lulls a child to sleep, to the trance-inducing rhythms of a techno party, to the rousing beats of a military march, rhythm has always held a peculiar power over people—of course, there are numerous exceptions. The music of speech—its prosody, its rising and falling, its stresses and pauses—also often conveys as much as the words themselves. Conversation researchers have long shown that speech does not proceed as a sequence of isolated utterances, but rather as a finely tuned interaction between conversation partners.2 Recent linguistic studies also suggest that patterns of prosodic emphasis exhibit surprising similarities between otherwise unrelated speech forms.3
Even speech itself contains similar riddles. A seemingly trivial expression like “Huh?” actually shows remarkable similarities across the globe.4 This observation suggests that certain forms of communication may emerge time and again wherever people need to quickly resolve misunderstandings and reestablish contact with one another. Rhythm and pitch appear to play a role even before birth. A recent review article indicates that prenatal exposure to speech may influence how newborns use pitch in their earliest vocalizations.5 This is especially interesting because pitch is associated with arousal and excitement in many languages and cultures. Long before a child understands words, it is already living in a world of melody, intonation, and sonic gesture.
When we turn to the useful and still relatively new apps for parents of newborns—the so-called “baby translators”—we encounter similar questions.6 Do cries associated with hunger, discomfort, or tiredness follow recurring patterns across cultures? The world of apps also offers help in understanding animal sounds. Even the plant world has now become part of this discussion. Recent studies of plant activity have inspired attempts to translate aspects of plant life into sounds, leading some observers to speak of a hidden music of the plant world.7 Whether understood as scientific sonification or as a poetic metaphor, such works reflect our deep need to understand and connect.8
Don’t the chirping crickets and the fireflies flickering through the darkness remind us of something deeply familiar? The rhythm, perhaps, of immersing oneself in the other? “This is the relationship that exists when one person meets another and perceives the other ‘I’—that is, devotion to the other—inner resistance; sympathy—antipathy. [. . .] The soul oscillates; it oscillates sympathy–antipathy, sympathy–antipathy, sympathy–antipathy.”9
Translation Joshua Kelberman
Image Abdul Rehman Khalid/Unsplash
Footnotes
- Guy Amichay, Vijay Balasubramanian, and Daniel M. Abrams, “A Widespread Animal Communication Tempo May Resonate with the Receiver’s Brain,” PLOS Biology 24, no. 4 (2026): e3003735.
- Elizabeth Couper-Kuhlen and Margret Selting, eds., Prosody in Conversation: Interactional Studies (Cambridge: Cambridge University Press, 1996).
- D. Robert Ladd and Amalia Arvaniti, “Prosodic Prominence Across Languages,” Annual Review of Linguistics 9 (2023): 171–193.
- Mark Dingemanse, Francisco Torreira, and N. J. Enfield, “Is ‘Huh?’ a Universal Word? Conversational Infrastructure and the Convergent Evolution of Linguistic Items,” PLOS ONE 8, no. 11 (2013): e78273.
- Elanie van Niekerk, Caroline Junge, and Aoju Chen, “The Influence of Prenatal Language Exposure on the Use of Pitch in Newborns’ Vocalisations: A Systematic Review,” First Language 46, no. 2 (2026): 305–334.
- E.g., Chatterbaby; see also Shihui Yu, Pam Birtill, Alison Fildes, Tang Tang, and Marion M. Hetherington, “Towards Developing a Baby Translator: An Exploration of How Infant Appetite Cues Are Understood,” Appetite 206 (2025): 107850. Newborns, however, already have their parents’ accent.
- Ulrich Schnabel, “Die geheime Melodie der Pflanzen” [The secret melody of plants], Die Zeit, no. 24 (May 27, 2026): 27.
- See, e.g., Lydia Denworth, “Brain Waves Synchronize when People Interact,” Scientific American, July 1, 2023.
- Rudolf Steiner, The Foundations of Human Experience, CW 293, translated by Robert F. Lathe & Nancy Parsons Whittaker (Hudson, NY: Anthroposophic Press, 1996); see also Leonhard Weiss, “Steiners Hypothese ‘Ich-Sinn’. Ein Beitrag zu einer heuristischen Lesart der waldorfpädagogischen Anthropologie [Steiner’s hypothesis of the “‘I’ sense.” A contribution to a heuristic reading of Waldorf anthropology],” Steiner Studies: International Journal for Critical Steiner Research 4 (2023): 1–32.
