The Bubbly Origins of Life
The origins of life as we know it here on Earth — a murky and complicated mystery spurring countless competing theories and research — remain inconclusive. Currently, abiogenesis offers one explanation, while asteroids provide a slightly different story. There are those who are confident that life is inevitable, but others are firm in stating that life on Earth started as a chance event.
These widely varying theories have been bolstered by the fact that there is no consensus on how the gases that existed on a lifeless Earth became the molecules that, almost 4 billion years later, led us here. But one new study suggests something very different.
In a paper recently published in ACS Central Science, Israeli researchers made digital models of 12 potential conditions that could have birthed life on Earth. They did this using a combination of gases — carbon (CO, CO2, or CH4) and nitrogen (N2 with or without HCN, or NH3 with or without HCN).
After setting up these conditions, it was time to model a "trigger." It is known that there must have been some trigger to turn these gases into the life-giving molecules that later created viable organisms. But this team looked beyond previous considerations of lightning or meteorites to trigger this change. They suggested that collapsing bubbles could be responsible for the transformation. That's right — collapsing bubbles.
Inside of collapsing bubbles, at the microscopic level, pressures and temperatures can exist in such extremes that they can cause chemical reactions. And, because bubbles can be found anywhere from deep under the ocean to the breaking of waves or the crashing of waterfalls, these researchers considered them as a possible trigger for the origins of life through a process known as sonochemical synthesis.
The team's model of initial Earthly conditions showed them what organic molecules could realistically be produced inside of these bubbles. The computer model reacted and resulted in the creation of transient and stable products.
Of these stable products were what are known as biologically relevant molecules — which could eventually form lipids, amino acids, and nucleotides. Hopefully, this model will be recreated physically and the results can be shown chemically, not just in a computer model, that life could potentially emerge from bubbles.