A new study questions one of the key theories of the origin of life on Earth, first established by Charles Darwin. He suspected that life first arose in shallow pools.
University College London researchers, however, have successfully created protoplasts in hot, alkaline sea water, similar to marine environments found near deep-water hydrothermal vents in the deepest areas of the world and not in the shallowest areas.
"There are several competing theories about where and how life began, and hydrothermal underwater sources are among the most promising locations for the beginnings of life – our findings now support this theory with solid experimental evidence," said the lead author of the study, Nick Lane, in a statement.
Earlier experiments unsuccessfully attempted to form protocells, which are considered to be one of the key building blocks for the evolution of cell-based life. However, the generation of simple molecule protocells naturally occurring was successful in cooler fresh water under tightly controlled experimental conditions, which later disassembled when duplicated in environments resembling hydrothermal wells.
"Other experiments used only a small number of types of molecules, mostly fatty acids of the same size, while in natural environments a larger number of molecules could be expected," said lead author Sean Jordan. [1
"In our experiments, we have created one of the essential components of life in conditions that reflect older environments more than many other laboratory studies," Jordan said. "We still do not know where life first formed, but our study shows that you can not rule out the possibility of hydrothermal deep-sea vents."
Hydrothermal ocean vents are found in places around the world that have only been around recently accessible to people through advanced technologies are chnology. Such marine features are air holes that eject minerals beneath the earth's crust. When in contact with the surrounding seawater, these minerals form a warm, nitrogen-rich environment characterized by "chimneys" that have been formed by years of mineral deposition and are able to seep out alkaline and acidic liquids. Overall, the environment provides an energy that is ripe for interactions between hydrogen and carbon dioxide that can form increasingly complex organic compounds.
As our knowledge of hydrothermal vents in the deep ocean has expanded, researchers have widely accepted the idea that life on Earth began in the very, very hot depths of the deepest parts of the oceans. But it's not that cut and dried. A 2017 study revived Darwin's original idea of proponents and opponents on both sides of the argument, especially as hydrothermal discharges were observed on other planets of our solar system.
"Space missions have found evidence that icy moons of Jupiter and Saturn could do it. We've never seen evidence of life on these moons, but if we want to find life on other planets or moons, studies like ours can help us helping to decide where to look, "Lane said.