SSS 2009-09-17（在线收听）

The early Earth’s oceans were home to a lot of interesting chemistry. Now scientists have found that amino acids thought to be present way back when could have been cooked into other compounds vital for life—an idea you should take with a grain of salt.

Four billion years ago, the planet was probably covered by a salty ocean, dotted with volcanic islands and short lived continents. German researchers recently mimicked some of the chemistry taking place along the coasts of the volcanic islands. They created an approximation of primordial seawater. Then they evaporated it, to simulate what went on at those volcanic coasts. They baked the residue, creating salt crusts.

At those high temperatures, amino acids interacted with metal ions in the salt crusts and were converted into other important biological molecules, such as pyrroles—which are part of the structures of chlorophyll in plants and hemoglobin in animals. The scientists presented their findings September 17th at the European Planetary Science Conference in Potsdam.

Over hundreds of thousands of years, these novel compounds could have built up along the volcanic coasts, creating materials for the first living cells. Which were really worth their salt.