The Earth was born about 4.5 billion years ago which was followed by the first living being much later. It is known that microbial life was the first to appear on the planet but the origins of life have rather remained a mystery. While it has been a long-standing theory that undersea hydrothermal vents were the birthplace of life, scientists now think it could also have originated from phosphorous lakes.
In a new study, scientists have solved the phosphate problem that has shrouded the origins of life for 50 years. Phosphorous is one of the key elements of the building blocks of life that make up DNA and RNA. Even though it is one of the main ingredients of life, the amount of phosphorus in nature is limited. Most phosphorus is in the form of calcium phosphate, making it inaccessible for the formation of life.
Researchers focused their study on alkaline lakes, like the Lonar Lake which tends to have a high concentration of carbonate salts. Alkaline lakes were found to have high amounts of phosphorus, about 50,000 times of the levels seen in seas, rivers and other types of lakes. To understand the mechanism behind high levels of phosphorus, researchers experimented with carbonate-rich water with different chemical compositions. They found that carbonate surpasses phosphate in the ability to bind with calcium. So, some phosphate is freely available in the waters of alkaline lakes.
“Carbonate-rich lakes may have been relatively common on early Earth due to strong chemical weathering of abundant, fresh volcanic rocks under early Earth’s CO2-rich atmosphere”, researchers explained in their paper inciting it is plausible for life to have originated from lakes.
A separate study adds to the plausibility of the conclusion, as it found that alkaline lakes also provide abundant cyanide, another key ingredient of life that is scarce and poisonous to humans. Lead author of the study, Jonathan D. Toner said, “It’s a straightforward idea, which is its appeal, It solves the phosphate problem in an elegant and plausible way.”
