How did life on Earth begin? Cracks may have been the key.

The discovery opens the door for scientists to devise experiments that could help answer one of the biggest scientific questions facing humanity: How did life on Earth begin? I started exploring biology.

Now, scientists at Munich’s Ludwig-Maximilians-University have taken an exciting step forward by showing how more complex molecules important for life were synthesized from the basic components of early Earth.

In the study published in the journal Nature, scientists replaced the test tube with a small network of branching cracks similar to the cracks that form naturally in rocks. They poured water through the cracks, along with key chemical components, and applied heat, mimicking a process similar to what can occur in porous rocks near hydrothermal vents in the ocean or geothermal pools.

They discovered that the heat flowing through these geological networks sorts and filters molecules, helping to create longer chains called biopolymers that are essential for life.

“This is a great demonstration that simple physical processes work to do things like this,” said Matthew Pasek, a professor of geosciences at the University of South Florida who was not involved in the study.

The question of how life began is so big that it transcends the traditional boundaries that divide science into different disciplines. Chemists, biologists, astrophysicists, and geologists all come to the table to try to answer this question.

Christoph Mast, a biophysicist at Ludwig Maximilian University in Munich, was interested in bridging these boundaries. His lab has designed an experimental setup that somewhat approximates the conditions in which the “prebiotic chemistry” that creates life occurs.

For decades, scientists have wrestled with the problem that early Earth was not a pristine laboratory with beakers, perfectly timed purification steps, and concentrated stocks of raw materials. It’s one thing to recreate life’s chemical reactions in the lab, but experiments that can be performed in a flask may be impossible at best under the chaotic conditions of the real world.

“If you think about the prebiotic earth, this prebiotic soup is very diluted and all these different things are reacting in a very uncontrollable way,” Mast said. Ta.

One problem in the past is that chemical reactions in the lab often produce byproducts that start unwanted reactions themselves, leaving scientists with only small amounts of critical materials. is. So how did early Earth brew enough of these building blocks for life to emerge?

When you try to understand it, The researchers cut through a branching network of interconnected cracks to An inert Teflon-like substance called FEP is sandwiched between two sapphire plates. The sapphire was brought to Accurate but This mimics the flow of heat on early Earth, perhaps near volcanoes or hydrothermal vents. They then poured water and basic chemical components into the crack network and watched what happened.

One proof-of-concept experiment used the simplest amino acid, glycine, and a substance called TMP that can react to combine two glycine molecules.

Such reactions would be difficult in water, Mast said, and TMPs were extremely rare on early Earth. Simply mixing these components in a beaker or in a geological crack without applying heat produces “negligibly small” amounts of more complex biopolymers, the researchers report. did.

However, applying a thermal gradient across the crack significantly increased biopolymer production. That’s important. Amino acids are important, but they are still far from life. For example, these same basic building blocks have been found in lifeless meteorites.

“To take things to the next level, we need to start making polymers. This is a fundamental step in creating the next realm of life,” Pasek said.

Don’t forget the pot

This setting raises the ultimate question of how life began: was it in a pond that may have existed on Earth’s surface, or in a hydrothermal vent similar to a deep-sea hydrothermal vent? I cannot go into the question of whether he was near the hole. Heat flux across rocks can occur in a variety of geological environments and was probably “ubiquitous” on the early Earth, Mast said.

But the experimental device can be used to test other questions about early chemistry on Earth. Mast then wants to create a network of fissures from the geological material to build a larger network of connected chambers.

This study is yet another reminder that elegant chemistry experiments can ignore a fundamental part of a primitive soup: the pot.

In 2021, a team of scientists discovered that in a famous experiment from the 1950s, the test tubes themselves, or rather the borosilicate glass they were made from, influenced the results.

When these scientists repeated their experiments with glass flasks, Teflon flasks, and Teflon flasks with a small amount of borosilicate glass, they found that glass was the key ingredient in catalyzing the reaction.

“In other words, casseroles are important for cooking the ‘primitive soup,'” Juan Manuel García-Ruiz, a professor at the International Physics Center of Donostia in Spain, who was involved in the experiment, wrote in an email.He praised the new work’s imaginative approach. And perhaps most importantly, it is “geologically plausible.”

“This may not be the only mechanism, but it is working, it is original, and above all it is an experimental demonstration,” García Ruiz said. “I think we need a more experimental approach to investigating the geochemical conditions on Earth when life first appeared.”