Archaea are more than just oddball lifeforms that thrive in unusual places — they turn out to be quite widespread. Moreover, they might hold the key to understanding how complex life evolved on Earth. Many scientists suspect that an ancient archaeon gave rise to the group of organisms known as eukaryotes, which include amoebae, mushrooms, plants and people — although it’s also possible that both eukaryotes and archaea arose from some more distant common ancestor.
As scientists learn more about enigmatic archaea, they’re finding clues about the evolution of the complex cells that make up people, plants and more.