New theory emerges about extraterrestrial communication: But what’s the connection to fireflies?

According to a recent study, advanced extraterrestrial communication may not rely on radio waves, but rather on subtle, repeated flashes of light. Surprisingly, fireflies could help us understand this phenomenon, potentially revolutionising long-standing assumptions about alien life.

For decades, the search for alien civilisations has primarily followed a technology-based approach. The world’s leading organisation in the search for extraterrestrial life, the SETI Institute, mainly monitors radio signals from distant exoplanets and attempts to detect heat emissions from hypothetical megastructures, such as Dyson spheres. This strategy is based on the assumption that extraterrestrial communication might resemble our own.

However, a new study proposes a radically different approach. Researchers suggest that communication among advanced extraterrestrials could be based on light signals, and that fireflies might offer surprising insights into how such a system could work.

The significance of fireflies

On Earth, fireflies generate regular, repeated light signals through internal chemical reactions. These flashes are primarily used for mating purposes, but the patterns vary between species, allowing individuals to recognise one another. While simple, these signals constitute an effective means of communication.

The researchers argue that a highly advanced alien civilisation could send messages into space in a similar manner. Flashes that initially appear random might, in fact, encode complex systems or function as repeated beacons, allowing other civilisations – potentially including humanity – to detect and decode them.

The universe is already full of natural but often poorly understood light bursts, meaning artificial signals could easily be concealed among them. Consequently, extraterrestrial communication could remain entirely undetected.

Anthropocentric bias in the search for alien communication

The authors highlight the problem of anthropocentric bias – the tendency to interpret non-human intelligence from a human perspective. This bias means we often search only for signals resembling our own forms of communication, potentially overlooking entirely different methods.

If extraterrestrial communication is indeed akin to that of fireflies, it could have profound implications, expanding our thinking and guiding science toward new detection strategies.

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Pulsars as possible analogues

The study also analysed the light signals from over 150 pulsars – rapidly rotating, strongly magnetised neutron stars. Pulsars emit regular electromagnetic radiation, which in some respects resembles the flashing patterns of fireflies.

While no artificial signals were identified, the researchers found several parallels between pulsars and biological, light-based communication. Based on these observations, they proposed strategies for recognising flashes that deviate from natural phenomena and could indicate intelligent origin.

Radio waves take a back seat

According to the research team, light-based communication is most likely to develop in civilisations that have moved beyond widespread use of radio waves. Interestingly, a similar trend is occurring on Earth, as modern communication satellites increasingly employ more targeted and concentrated signals.

This suggests that an advanced civilisation may deliberately choose alternative communication methods that are less conspicuous yet highly efficient.

A new direction in the search for extraterrestrial life

Estelle Janin, one of the study’s authors, emphasises that communication is a fundamental characteristic of all life and can take many diverse forms. Studying non-human communication may help broaden our perspective on alien intelligence.

The researchers stress that their work is primarily a thought experiment, intended to encourage collaboration between SETI researchers and animal communication experts. Their ultimate goal is to inspire new, creative approaches to studying extraterrestrial communication and seeking out alien life.