Mono Lake in California. Credit: Ron Reiring / Wikimedia Commons (CC BY 2.0)

Life on earth appeared billions of years ago in an accidental way, according to the scientific discoveries made.

An investigation by scientists of the University of Washington has determined that the waters of lakes with high content in phosphorus, have the necessary conditions for the emergence of organic molecules.

Life on earth requires phosphorus, moreover, it is one of the six main chemical elements for its appearance, and is present in the DNA Y RNA.

The researchers wondered how Primitive earth got a match for life to appear.

Jonathan Toner, research assistant professor of Earth and Space Sciences of the University of Washington and lead author of the study, said in a statement:

For 50 years, what is called ‘the phosphate problem’ has plagued studies on the origin of life. ”

Phosphorus: conducive to life

The investigation focused on carbonate-rich lakes, formed in dry environments where water drains through surrounding landscapes. These types of lakes are found on all continents and are also called alkaline lakes.

The researchers proceeded to measure the amounts of phosphorus in lakes rich in carbonates, the main ones being: Mono Lake in California, the Lake Magadi in Kenya and the Lonar Lake in India.

Lake Magadi in Kenya, a lake rich in carbonates whose bed is made of volcanic rock. Credit: Stig Nygaard / Flickr

It was determined that carbonate lakes possessed 50,000 times higher phosphorus levels to sea water, rivers or other lakes. This suggests the existence of some natural mechanism that allows the accumulation of phosphorus.

At present, carbonate-rich lakes host microbial life and even flocks of flamingos in Magadi, so researchers have suggested that life on Earth would have originated in this place.

To carry out the research, carbonate-rich water was collected in bottles in order to determine how lakes accumulate phosphorus and how high concentrations of phosphorus could reach a lifeless environment.

Waters in carbonate-rich lakes show a substance that is more abundant than even on earth: calcium. Tests showed that calcium binds carbonate leaving phosphate freely available in the water.

Mono Lake in California has no outflow, which allows salts to accumulate over time. The high concentration of salts in this carbonate-rich lake can become pillars. Credit: Matthew Dillon / Flickr

Chemical reactions originated life

The lakes analyzed showed that their phosphate levels can increase 1 million times superior to seawater. This happened especially when the waters of the lakes evaporated in the dry seasons.

David Catling, professor of Earth and Space Sciences of the University of Washington He said in a statement:

Extremely high levels of phosphate in these lakes and ponds would have caused reactions that put phosphorus in the molecular building blocks of RNA, proteins and fats, all of which were necessary for life to continue. ”

In addition, another factor encouraged life to originate: the air rich in carbon dioxide because the primitive Earth was a volcanically active place, approximately 4 billion years ago.

These conditions enabled the formation of carbonate-rich lakes that reached very high levels of phosphorus.

The colored dots show the level of phosphorus measured in different carbonate-rich lakes around the world. Existing carbonate-rich lakes may contain up to 50,000 times the phosphate levels found in seawater, with the highest levels measured in the Goodenough and Last Chance lakes system in British Columbia (yellow dots). Credit: Toner and others / PNAS

Toner added:

Primitive Earth was a volcanically active place, so it would have had many fresh volcanic rocks reacting with carbon dioxide and supplying carbonate and phosphorus to the lakes.

Primitive Earth could have harbored many lakes rich in carbonate, which would have had phosphorus concentrations high enough to begin life. ”

The scientific study has been published in the journal Proceedings of the National Academy of Sciences.

Source: University of Washington