Evolving intelligent life took billions of years − but it may not have been as unlikely as many scientists predicted

The Sun's distance from Earth allows it to be habitable for life. DrPixel/Moment via Getty Images

A popular model of evolution concludes that it was incredibly unlikely for humanity to evolve on Earth, and that extraterrestrial intelligence is vanishingly rare.

But as experts on the entangled history of life and our planet, we propose that the coevolution of life and Earth’s surface environment may have unfolded in a way that makes the evolutionary origin of humanlike intelligence a more foreseeable or expected outcome than generally thought.