Scientists from the University of Washington analyzed the chemical composition of some alkaline lakes in Canada and discovered that life may arise from such ecosystems. Due to climatic conditions, phosphates necessary for RNA and DNA construction accumulate in Last Chance Lake, and the high alkaline concentration helps accumulate in the water column carbon, nitrogen and other substances that living organisms cannot do without.

According to Charles Darwin, life on our planet may have emerged by chance in a “little, warm pond” about four billion years ago. But for the transformation of molecules from inorganic to organic, special conditions are required – a very high concentration of phosphates, phosphoric acid salts. These substances form the basis of the cell membrane, the synthesis of amino acids, and even RNA and DNA, the key molecules of real life.

Theoretically, this problem was solved in 2019 when alkaline lakes (bodies of water with high salt content) were proposed as “warm ponds”. Later, scientists discovered that natural conditions can create a phosphate concentration million times higher than normal.

Now researchers decided to find and study a similar environment. The article was published in the journal Communications Earth & Environment.

Scientists chose Last Chance Lake in British Columbia, Canada; It has been listed as the richest lake in natural phosphates since the 1990s. The depth of the Last Chance is less than half a meter, it is located on basalt rocks, the water level is unstable – the reservoirs are fed mainly by precipitation and underground flow. Scientists sampled this lake three times from 2021 to 2022; The most alkaline period was September.

It turns out that cycles of accumulation of phosphorus and sodium carbonate in the shallow lakes of the early Earth may indeed have provided the necessary conditions for the origin of life. Phosphates helped water bodies store carbon, nitrogen, and sulfur, as well as carbon dioxide and volcanic sulfides needed for carbon metabolism.

“This study adds to the growing evidence that evaporating soda lakes represent environments that meet the requirements of origin-of-life chemistry and accumulate high concentrations of essential components,” said study co-author David Catling.

Scientists also compared Last Chance’s chemical composition to nearby Goodenough Lake, where cyanobacteria fix nitrogen from the air. Goodenough is deeper and the water in it is not as turbid and salty – cyanobacteria consume phosphates, preventing them from accumulating. The water in Last Chance, on the contrary, is so salty that it inhibits the development of organisms – very few algae live there. This makes the reservoir an analogue of the still lifeless Earth.

The new results could help researchers better reproduce in laboratories the conditions of early Earth or other celestial bodies potentially suitable for the development of life, such as the sub-icy ocean on Enceladus, a moon of Saturn. Lakes similar to the alkaline Last Chance lakes may exist on early Mars.