Science fiction often imagines Earth’s galactic neighborhood teeming with hyper-advanced extraterrestrial civilizations, but the actual cosmos near us may be far quieter.
A study published in the International Journal of Astrobiology, led by Chris Doughty, a professor of ecoinformatics at Northern Arizona University, proposes that the evolution of complex life on exoplanets depends heavily on cumulative plant energy rather than just the passage of time. Although many of the planets orbiting Earth’s stellar neighbors are several billion years older than our world, worse conditions for cumulative photosynthesis mean life on those planets likely evolved much more slowly.
Among 29 nearby exoplanets, worlds outside our solar system that could potentially have liquid water, the team identified only two where life might have progressed beyond Earth’s evolutionary stage. Those planets, GJ 1061c and K2-3d, are larger, hotter, brighter, and older than most Earth-like planets in our stellar neighborhood. Three others could have reached a stage roughly comparable to Earth’s Mesozoic Era, the age of dinosaurs.
It's far more unlikely that these are competant "scientists."
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