New Research Suggests the Universe May Be Teeming with Alien Minds

Scientists debate whether human-level intelligence is a cosmic rarity or commonplace in the universe.

Published on Feb. 22, 2026

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New research is challenging the long-held 'hard steps' theory that suggests human-level intelligence is an extremely rare evolutionary occurrence in the universe. Geomicrobiologist Dan Mills and other scientists argue that certain evolutionary transitions may not be as improbable as previously thought, opening up the possibility that advanced alien civilizations could be more common than we realize. However, others like Anders Sandberg warn that even if intelligent life exists elsewhere, it may not necessarily be detectable or interested in contacting us.

Why it matters

The debate over the rarity or prevalence of intelligent alien life has profound implications for our understanding of humanity's place in the cosmos. If advanced civilizations are indeed common, it could mean we are not alone and may one day make contact with extraterrestrial beings. Conversely, if human-level intelligence is an evolutionary fluke, it could suggest we are truly unique and the only intelligent life in the observable universe.

The details

The 'hard steps' theory argues that the evolution of human-level intelligence required a series of highly improbable transitions that only occurred once on Earth. However, Mills and other researchers propose alternative explanations, such as the 'priority effect' where the first successful lineage of intelligent organisms alters the environment to prevent competitors. Sandberg also notes that the difficulty of a transition may not be the key factor, but rather turning it into a survival advantage. Environmental conditions on a planet can also make certain evolutionary steps more or less likely.

  • The 'hard steps' theory was published in a 2025 review in the journal Science Advances.
  • Human ancestors first appeared around 7 million years ago when our lineage split from chimpanzees.

The players

Dan Mills

A geomicrobiologist and affiliate member of the Penn State Extraterrestrial Intelligence (PSETI) Center who previously supported the 'hard steps' theory but has since reconsidered his views.

Anders Sandberg

A researcher at the Mimir Center in Stockholm and senior research fellow at the Future of Humanity Institute at Oxford University who approaches the topic of the rarity of intelligent life with an open mind.

Jason Wright

An astronomer and co-author of the 2025 study that reassessed the 'hard steps' theory.

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What they’re saying

“At first, I was looking at what makes the hard steps theory look correct, and there is evidence that arguably supports it. To me, the strongest evidence for hard steps is that there do appear to be evolutionary transitions in Earth's past that needed to happen for us to exist and it looks like they only happened once, but even if hard steps are real, we don't know how to identify them.”

— Dan Mills, Geomicrobiologist (Science Advances)

“It's not always easy to tell if something was a hard step. It is possible that life itself is exceedingly rare, especially intelligent life, but another possibility is that intelligent civilizations are common but end up annihilating themselves.”

— Anders Sandberg, Researcher (Science Advances)

“Intelligent life always manages to screw things up. So the argument is self-annihilation, and I do believe intelligence irrevocably destroys itself, which is a strong sociological thesis. Most of us don't want it to be true, but that doesn't mean it isn't.”

— Anders Sandberg, Researcher (Science Advances)

What’s next

The debate over the prevalence of intelligent alien life is likely to continue as scientists gather more data and refine their theories. Future research may focus on identifying potential technosignatures that could provide clues about the existence and behavior of advanced civilizations elsewhere in the universe.

The takeaway

This research highlights the ongoing scientific debate over whether human-level intelligence is a rare cosmic phenomenon or potentially more common in the universe. While the possibility of encountering alien minds is intriguing, the findings also suggest that even if such civilizations exist, they may not be easily detectable or interested in contacting us, raising questions about humanity's place in the grand cosmic scheme.