Studying Mars and complex chemical systems may help understand how life began
Washington, Nov 15 : Scientists have determined that to understand how life began on Earth, it is important to study the chemistry that preceded early life, as well as studying Mars.
These two new approaches for understanding how life started on our planet were discussed at a European Science Foundation (ESF) and COST ‘Frontiers of Science’ conference in Sicily, which was held recently.
The first applies complex systems theory to the chemistry that preceded early life. The second involves studying Mars, which may yield ample evidence about what Earth was like when life evolved.
Complex systems chemistry uses computer models to simulate combinations of reactions, involving membrane-forming reactions, self-replicating nucleic acids and metabolic energy-producing reactions.
Then it examines how these systems develop in time and space.
One promising area is the discovery of reaction systems that lead to the spontaneues generation of chiral asymmetry.
It is a universal property of life that compounds such as amino acids and sugars exist exclusively in a one-handed form although both forms are equally likely from an energetic point of view.
It is quite difficult to achieve this asymmetry in non-living chemical reactions. Chemistry tends to create equal proportions of the different forms, which behave like objects and their mirror images.
“The recipe for asymmetry is the co-occurrence of positive and negative feedback loops within such systems,” said Gunter Von Kiedrowski, of Ruhr Universitat Bochum in Germany.
Complex systems chemistry cannot tell the story of life entirely.
“We are in the same position as the physicists trying to understand the origin of the universe,” said Kiedrowski.
“We will not know exactly how life began, because we do not know the precise conditions at the time, but we can get a good model of how it could have happened with this approach,” he added.
Understanding the context of early life from the evidence on Earth is difficult. Because the Earth’s crust is so active, there is very little surface rock remaining from the time when life originated, before 3.5 billion years ago.
On Mars, by contrast, about 50 percent of the surface is from before 3.7 billion years ago, so there is a lot more to work with.
“Mars may be our best bet to find out about life’s origins on Earth,” said Tanja Zegers, a geoscientist from Utrecht University in the Netherlands. (ANI)