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What would it mean if the Great Filter occurred early in the development of life?

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artist's conception of Kepler-186f — extraterrestrial intelligence An artist's conception depicts Kepler-186f, the first Earth-sized extrasolar planet found in its star's habitable zone.

The "Great Filter" is a concept used to explain the Fermi paradox, suggesting that some step in the evolutionary chain from the formation of a habitable planet to the development of a space-faring civilization is extremely improbable.1

If the Great Filter occurred early in the development of life—such as at the origin of life itself or during the transition from single-celled prokaryotes to complex eukaryotes—it implies that the emergence of intelligent life is an exceptionally rare event.2

From this perspective, humanity may be one of the very few, or perhaps the only, species to have successfully navigated these initial evolutionary hurdles. This would mean that we are not necessarily "lucky" to have survived a future catastrophe, but rather that we are a statistical anomaly because we managed to overcome a barrier that prevents the vast majority of life from ever reaching an advanced stage. Consequently, the lack of evidence for extraterrestrial intelligence would be explained by the fact that life elsewhere simply failed to progress beyond those early, difficult stages.21