Advanced alien civilizations could be communicating 'like fireflies' in plain sight, researchers suggest
A new paper posits that advanced alien civilizations may communicate through subtle flashes, like fireflies do on Earth. The thought experiment suggests that we need to avoid human biases in our search for extraterrestrial life.

A new paper suggests that alien civilizations may communicate in ways that we do not currently expect, such as periodically flashing like fireflies. However, there is currently no evidence to support this theory. (Image credit: Trevor Williams via Getty Images)
Advanced alien civilizations may communicate via a series of flashing lights, similar to how fireflies do, a new paper hints. This would potentially make extraterrestrials much harder to spot if we continue to rely on our current observation techniques, the researchers argue.
However, while this thought experiment raises interesting questions about alien intelligence, it does not provide any evidence that these signals actually exist.
So far, the quest to uncover alien intelligence has focused on finding evidence of distant human-like civilizations. For example, the Search for Extraterrestrial Intelligence (SETI) Institute — the world's leading organization dedicated to searching for alien life — spends most of its time searching for radio signals from distant exoplanets or heat given off by technological megastructures, such as the theoretical Dyson sphere.
However, some scientists believe that these searches suffer from an "anthropocentric bias" — meaning we're trying to understand nonhuman entities through a distinctly human lens — and do not account for potential civilizations that are wholly different from our own. Due to this bias, we may be overlooking promising signs of life.
In the new study, uploaded Nov. 8 to the preprint server arXiv, researchers proposed a new way that an alien civilization could communicate — by flashing to one another like fireflies. These flashing signals could be used for specific and complex communications. However, the researchers argue that they are more likely being widely broadcast to other civilizations, like a luminous repeating beacon. (This paper has not yet been peer reviewed, but is now under consideration for publication in the journal PNAS.)

Researchers argue that regularly repeating firefly-like flashes of light from alien civilizations may currently be going under the radar. This photo shows stars in the "cosmic fireflies" galaxy Abell 2163, which was unrelated to the new study. (Image credit: ESA/Hubble & NASA)
On Earth, fireflies communicate via a series of . These flashes are mainly used to find mates. But while these signals are simple, they do allow distinct firefly species to tell each other apart.