Ancestor of All Life on Earth Had Steamy Beginning

The mysterious common ancestor of all life on Earth may have lived in hot springs that were iron-rich and oxygen-poor, a new study finds. The last universal common ancestor, or LUCA, is what scientists call the forerunner of all living things. To learn more about how and where LUCA might have lived, researchers analyzed 6.1 million genes from prokaryotes — microscopic, single-celled organisms that lack distinct cell nuclei.