Geologists, often mocked by the fictional physics Nobel Laureate Sheldon Cooper of The Big Bang Theory believe the presence of oceans, continents and plate tectonics on Earth is the most likely reason why there is no evidence of advanced extraterrestrial civilisations, according to new research by University of Texas at Dallas and the Swiss Federal Institute of Technology in Zurich.
Published in Nature’s Scientific Reports, the paper explores the lack of “active communicative civilisations (ACC)” and suggest that a change to the infamous Drake Equation.
The Drake Equation is a formula which astronomers use to estimate the number of intelligent civilisations in our galaxy capable of communicating with humans. However, we haven’t found any evidence to support this, a mystery known as the Fermi Paradox.
The Fermi Paradox is the apparent contradiction between the high probability of extraterrestrial life existing in the universe and the lack of evidence or contact with such civilizations. Named after physicist Enrico Fermi, who famously asked, “Where is everybody?” during a casual conversation in 1950, the paradox highlights the discrepancy between the expectation that the universe should be teeming with life and the reality that we have not observed any signs of it.
The paper believes that they have resolved the issue of the Fermi Paradox with the type of tectonic activity on planets, which affects biological evolution. There’s evidence that a shift from simple tectonics to modern plate tectonics happened between 1.0 to 0.541 billion years ago, speeding up the development of complex life on Earth.
We also believe that both continents and oceans are necessary for intelligent civilizations. Early life needs water, but advanced life that can create technology needs land.
To explain the Fermi Paradox, the study suggests adding two new factors to the Drake Equation:
- The fraction of habitable planets with both significant continents and oceans.
- The fraction of those planets that have had plate tectonics for at least 0.5 billion years.
These factors are very small, which means it’s rare for planets to have the right conditions for intelligent civilizations. This scarcity might explain why we haven’t found any evidence of them.
One part of the Drake Equation refers to the fraction of life-bearing planets where intelligent life emerges. The new research suggests that the necessity for large oceans, continents and plate tectonics—the latter lasting for over 500 million years—should also be considered.
Dr Robert Stern, a professor of sustainable wrote in the paper published in Nature: “Life has been around on Earth for about four billion years, but complex organisms like animals didn’t appear until about 600 million years ago, which is not long after the modern episode of plate tectonics began. Plate tectonics jump-starts the evolution machine, and we think we understand why.”
Plate Tectonics refers to a theory that says that the earth’s lithosphere – its upper mantle and crust – is split into sections called plates that move. These movements created mountains, volcanoes, and most importantly oceans.
Basically, Earth’s plate tectonics and the existence of continents and oceans, are crucial to the existence of advanced life. By adding these factors to the Drake Equation—foc (fraction of planets with significant continents and oceans) and fpt (fraction with long-term plate tectonics)—the authors show that the probability of finding such planets is very low (less than 0.00003 to 0.002). This scarcity of suitable conditions could explain the lack of evidence for active communicative civilisations, addressing the Fermi Paradox.
