The origins of life

The doctrine of Spontaneous Generation holds that organic life could and does arise from inorganic matter. As late as the 17th century, there were recipes to "create" life.

The origins of life

Subterranean Surprises Hazen, a mineralogist, is investigating how the first organic chemicals—the kind found in living things—formed and then found each other nearly four billion years ago.

He began The origins of life research inabout two decades after scientists discovered hydrothermal vents—cracks in the deep ocean floor where water is heated to hundreds of degrees Fahrenheit by molten rock.

The vents fuel strange underwater ecosystems inhabited by giant worms, blind shrimp and sulfur-eating bacteria. Hazen and his colleagues believed the complex, high-pressure vent environment—with rich mineral deposits and fissures spewing hot water into cold—might be where life began. Hazen realized he could use the pressure bomb to test this theory.

If something were to go wrong, the ensuing explosion could take out a good part of the lab building; the operator runs the pressure bomb from behind an armored barrier.

In his first experiment with the device, Hazen encased a few milligrams of water, an organic chemical called pyruvate and a powder that produces carbon dioxide all in a tiny capsule made of gold which does not react with the chemicals inside that he had welded himself.

He put three capsules into the pressure bomb at degrees and 2, atmospheres. And then he went to lunch. When he took the capsules out two hours later, the contents had turned into tens of thousands of different compounds.

The origins of life

In later experiments, he combined nitrogen, ammonia and other molecules plausibly present on the early earth. In these experiments, Hazen and his colleagues created all sorts of organic molecules, including amino acids and sugars—the stuff of life.

Before them, origins-of-life research had been guided by a scenario scripted in by Charles Darwin himself: Miller set up a container holding water representing the early ocean connected by glass tubes to one containing ammonia, methane and hydrogen—a mixture scientists of the day thought approximated the early atmosphere.

A flame heated the water, sending vapor upward. In the atmosphere flask, electric sparks simulated lightning. But over the next few days, the water turned deep red.

Miller had created a broth of amino acids. His work soon led him to a more surprising conclusion: Cracking open space rocks, astrobiologists have discovered amino acids, compounds similar to sugars and fatty acids, and nucleobases found in RNA and DNA.

Abiogenesis - Wikipedia

But NASA, then starting up its astrobiology program, was looking for evidence that life could have evolved in odd environments—such as on other planets or their moons.

How did the right building blocks get incorporated? Amino acids come in multiple forms, but only some are used by living things to form proteins.

How did they find each other? In a windowed corner of a lab building at the Carnegie Institution, Hazen is drawing molecules on a notepad and sketching the earliest steps on the road to life.

It was probably just a few molecules here and there in a vast ocean.

BBC - Earth - The secret of how life on Earth began

He thinks that rocks—whether the ore deposits that pile up around hydrothermal vents or those that line a tide pool on the surface—may have been the matchmakers that helped lonely amino acids find each other. Rocks have texture, whether shiny and smooth or craggy and rough.

Molecules on the surface of minerals have texture, too. An amino acid that drifts near a mineral could be attracted to its surface. Kateryna Klochko is preparing an experiment that—when combined with other experiments and a lot of math—should show how certain molecules stick to minerals.

Do they adhere tightly to the mineral, or does a molecule attach in just one place, leaving the rest of it mobile and thereby increasing the chances it will link up to other molecules?

Klochko gets out a rack, plastic tubes and the liquids she needs. She puts a tiny dab of a powdered mineral in a four-inch plastic tube, then adds arginine, an amino acid, and a liquid to adjust the acidity.Inside you'll learn just how mysterious this all is, as we reveal the different scientific theories on the origins of life on Earth.

How did molecules first make the leap from non-living to living? An English chemist may have solved part of the mystery. The Origins of Life A mineralogist believes he’s discovered how life’s early building blocks connected four billion years ago A fossil collector since childhood, Bob Hazen has come up with new scenarios for life's beginnings on earth billions of years ago.

After the s, the scientists on the quest to understand life's origins split into three groups. Some were convinced that life began with the formation of primitive versions of biological cells.

Origin of Life - Spontaneous Generation For millennia, the Origin of Life was thought to be the result of Abiogenesis (also known as "Spontaneous Generation").

The doctrine of Spontaneous Generation holds that organic life could and does arise from inorganic matter. Watch video · An origin of life scenario must explain DNA rich in specifications for proteins, but many proteins are necessary to read the instructions and reproduce the DNA; a conundrum.

BBC - Earth - The secret of how life on Earth began