Scientists: the Universe found to have its own musical rhythm

Fireflies, crabs, birds, and humans communicate in the same rhythm: scientists have discovered a mysterious coincidence in nature. Researchers from Northwestern University in the US noticed that in the mangrove forests of Thailand, fireflies Pteroptyx malaccae and nearby crickets were producing signals at nearly the same frequency — about 2.4 hertz, or 145 beats per minute. This observation launched a large-scale study, the results of which have been published in the journal PLOS Biology.

Intrigued by the finding, scientists analyzed numerous studies of communication in the animal world — and discovered something striking. The rhythmic signals of the most diverse creatures fall within a common range — approximately 0.5 to 4 hertz, or 30 to 240 beats per minute. This "universal tempo" unites species separated by millions of years of evolution that differ drastically in size and body structure: from tiny fireflies and fiddler crabs to fish, birds, great apes, and humans. An additional analysis of 124 recordings from the Xeno-Canto wildlife sound archive made it possible to identify 50 species with regular rhythmic signals. They also predominantly fell within this range, with the most commonly occurring frequency being around 180 beats per minute.

But what explains this coincidence? The researchers suggested that the answer lies in the structure of the nervous system. Neurons do not respond to incoming information instantaneously: their activity can be influenced by signals received over the preceding several hundred milliseconds. Therefore, neural circuits may be particularly good at processing information arriving at a certain rate.

A computer model supported this hypothesis. Simple neural circuits tuned to an internal tempo of about 120 beats per minute responded best to signals at a similar frequency. Music perception researcher Henkjan Honing from the University of Amsterdam, who was not involved in the study, called the possible existence of a shared rhythm among such different species intriguing and noted that most popular Western music also falls within this range — around 120 beats per minute.

The observation is also consistent with research on human rhythm perception. According to cognitive scientist Nori Jacoby from Cornell University, people are capable of synchronizing with a wide range of rhythms, yet perception and reproduction of a beat are typically most effective at approximately 85–120 beats per minute.

However, it is too early to put a period at the end of this story. Scientists do not yet consider neural processing to be the sole explanation. In Honing's view, the tempo of communication may also be influenced by other biological rhythms — for example, body movements or breathing. Why such different species independently use similar signal transmission rates is a question that remains to be answered.