A study from the University of Oxford (UK) has revealed the extremely important metal that has driven the evolution of life on Earth, contributing to the emergence of humanity. This will also serve as a significant indicator in the search for intelligent extraterrestrial life.
The article published in the journal PNAS asserts that this special element is iron. Iron is an essential nutrient that all forms of life require for growth and development, and according to the authors, it is one of the leading factors that drive evolution.
Analyzing iron in the atmospheres of exoplanets could help identify planets capable of forming intelligent life – (Image: Pixabay/CC0 Public Domain)
“The initial amount of iron in Earth’s rocks was established by planetary accretion conditions, during which Earth’s metallic core separated from its rocky mantle,” explained Associate Professor Jon Wade, a planetary materials scientist from the Department of Earth Sciences at the University of Oxford.
According to Professor Wade, too little iron, as found on Mercury, would make it difficult for life to emerge. Too much, as on Mars, would hinder the retention of water on the surface and prevent the stimulation of complex life development.
The iron conditions on primitive Earth, according to models created by the research team, were optimal for maintaining water on the surface. Iron could also dissolve in seawater, providing simple life forms with a favorable starting point.
However, by the Great Oxidation Event (2.4 billion years ago), the increase in oxygen reacted with iron, forming iron oxide, which drastically reduced the amount of dissolved iron. According to Professor Hal Drakesmith from the MRC Weatherall Institute of Molecular Medicine at the University of Oxford, a co-author, life began to face difficulties and had to find new ways to survive.
A powerful evolutionary process began, such as the emergence of multicellular organisms and symbiotic lifestyles, to utilize scarce nutrients more effectively. This ongoing scarcity drove living organisms to become extremely complex, ultimately leading to the development of intelligent species like humans.
According to Phys.org, the aforementioned analysis opens a new path for the search for extraterrestrial life, or even the fortunate discovery of an entire extraterrestrial civilization.
Professor Drakesmith explains that the conditions that ensure basic life, which we have previously used as a basis for searching, may not necessarily support the evolution of life into complex forms. Therefore, by assessing the amount of iron in the atmospheres of exoplanets, it is possible to narrow down the search scope and identify planets that have the potential to develop intelligent life.
