Life can emerge from a lake that is rich in phosphorus, Life as we know it needs phosphorus. It is one of the six basic chemical elements of life, forming the backbone of DNA and RNA molecules, acting as the basic currency for energy in all cells and securing the lipids that separate cells from their environment.
The so-called “phosphate problem” has obscured the original study for 50 years.
The problem is that the chemical reactions that make up the building blocks of living things require a lot of phosphorus, but phosphorus is rare. This study focuses on carbonate-rich lakes that form in arid environments at depths that flow into the water from the surrounding landscape. Due to high evaporation rates, sea water is concentrated in saline and alkaline solutions or at high pH. Such lakes, also known as lye or soda lakes, exist on all seven continents.
Although the exact concentration depends on where and in what year the sample was taken, the researchers found that carbonate-rich lakes have up to 50,000 times the phosphorus content in seawater, rivers and other types of lakes.
Such high concentrations indicate a common natural mechanism that stores phosphorus in these lakes.
Today, this carbonate-rich lake is biologically rich and holds the life of germs for the famous flamingo flock at Lake Magadi. These creatures affect the chemistry of the lake. For example, researchers conducted laboratory experiments with carbonate-rich water bottles with different chemical compositions to understand how lakes accumulate phosphorus and how high phosphorus concentrations can be achieved in a lifeless environment.
The reason for the high phosphorus content in these waters is because of the carbonate content. In most lakes, calcium, which is far more common on Earth, binds to phosphorus and forms hard calcium phosphate minerals whose lives have no access. In carbonate-rich waters, carbonate exceeds phosphate and binds calcium, with some unbound phosphates. Laboratory tests that combine ingredients in different concentrations show that calcium binds to carbonate and phosphate remain available in water.
Phosphate levels in seawater can even increase millions of times if the water in the lake evaporates during the dry season, on the beach or in a pond that is separated from the main part of the lake.
Very high phosphate levels in lakes and ponds will trigger a reaction that puts phosphorus into the building blocks of RNA molecules.
Carbon dioxide-rich air from the early earth some four billion years ago would be ideal for making such lakes and allowing them to reach maximum phosphorus levels. Lake containing carbon tends to form in the atmosphere with high carbon dioxide content. In addition, carbon dioxide dissolves in water, which creates acidic conditions in which phosphorus is released effectively from rocks.
Another recent study by the two authors shows that this type of lake can also contain lots of cyanide to support the formation of amino acids and nucleotides, the building blocks of proteins, DNA and RNA.
So far, researchers have struggled to find a natural environment with enough cyanide to maintain the origin of life. Cyanide is toxic to humans, but not to primitive germs, and is important for the type of chemical that easily creates the building blocks of life.