Professor shares opinion on where life began

In an article titled "Russian hot springs point to rocky origins for life" New Scientist writer Colin Barras tackles the question that strikes at the very heart of one of the deepest mysteries in the universe: How did life begin on Earth?

New findings challenge the widespread view that it all kicked off in the oceans, around deep-sea hydrothermal vents. Life may have begun on land instead – just as Darwin thought.

Although conventional wisdom has it that hydrothermal vents on the ocean floor offered an ideal chemical environment for the earliest life, Paul Knauth, a geologist in ASU's School of Earth and Space Exploration, thinks life may not have begun in the sea. "The early ocean was a deathtrap of hot salty water," he says. "I like the idea of a non-marine origin."

Knauth has analyzed the oxygen isotopes in the silica-rich rocks deposited early in Earth's history, from which you can work out temperatures at the time the rocks formed. He says that the entire planet was much hotter than anyone suspected – surface temperatures of 50 to 80 degrees Celsius may have been common. The seas also were twice as salty as today, because so-called "evaporitic" deposits – that locked away vast quantities of salt – had not begun to form.