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We know that evolution is how life adapts to its environment over time. This adaptation is driven by variability and by competition within populations of organisms. Evolution allows for the most successful traits within a population to continue on through reproduction. We have good reason to think that this process of selection for certain traits has been around for as long as living things and maybe even before that. It’s possible that the evolution of chemical systems was one necessary step in the origin and development of life on Earth. If that’s the case, where do you think these early evolving systems might have been found?

Since we know water is such an important solvent for life, many have considered whether the first evolving chemical systems developed in “warm little ponds” or in tide pools or maybe around hydrothermal vents or in hot springs. These kinds of places have water as well as ways of concentrating molecules together and providing energy sources from sunlight or from heat. We also need to consider how some early chemical reactions may have been catalyzed: that is, were there molecules or maybe minerals present that caused chemical reactions to happen? Clays and some kinds of minerals might have been good at doing this. There are also some molecules that act as natural catalysts. For instance, RNA (ribonucleic acid) is a molecule that’s a lot like DNA (deoxyribonucleic acid), but it’s often just single-stranded ( DNA is double-stranded) and we now know that RNA can catalyze reactions like those that form bonds between amino acids to turn them into proteins.

It’s important for the scientists who study these questions to consider the environments on the early Earth and possible reactions that could have happened then as well as to look at how life functions in our modern world. While some people are working in labs to better understand cellular functions and how life catalyzes reactions in different environments, there are other researchers who are studying old rocks to better understand what the chemical and physical environment of the early Earth’s surface was. If we want to better understand how life may have gone from an evolving chemical system to the great diversity of living, evolving things that we see today, then we need people from a lot of different scientific backgrounds to work together to put together the pieces of the puzzle.

We know that evolution is how life adapts to its environment over time. This adaptation is driven by variability and by competition within populations of organisms. Evoluation allows for the most successful traits within a population to continue on through reproduction. The most successful traits aren’t always the ones that might seem to be the best. We have good reason to think that this process of selection for certain traits has been around for as long as living things and maybe even before that. It’s possible that the evolution of chemical systems was one necessary step in the origin and development of life on Earth that preceded even the development of cells. If that’s the case, where do you think these early evolving systems might have been found?

Since we know water is such an important solvent for life, many have considered whether the first evolving chemical systems developed in “warm little ponds” or in tide pools or maybe around hydrothermal vents or in hot springs. These kinds of places have water as well as ways of concentrating molecules together and providing energy sources from sunlight, from motion (like waves or tides), or from heat. We also need to consider how some early chemical reactions may have been catalyzed: that is, were there molecules or maybe minerals present that caused chemical reactions to happen? Clays and some kinds of minerals might have been good at doing this. There are also some molecules that act as natural catalysts. For instance, RNA (ribonucleic acid) is a molecule that’s a lot like DNA (deoxyribonucleic acid), but it’s often just single-stranded ( DNA is double-stranded), and we now know that RNA can catalyze reactions like those that form bonds between amino acids to turn them into proteins. Forming these bonds, known as peptide bonds, and making proteins is something that RNA does inside of our own cells today. Not only can RNA catalyze reactions, but it also acts as an information storage molecule and might have been the primary source for carrying information before DNA existed. This has led some scientists to propose that a so-called “RNA World” existed early in the history of life, where RNA was acting as a catalyst and information carrier for all (or at least most) of the living things that existed at that time. However, even getting to an RNA World would have required a lot of steps in the processes of chemical evolution, and these are steps that we’re still trying to learn more about today.

It’s important for the scientists who study these questions to consider the environments on the early Earth and possible reactions that could have happened then as well as to look at how life functions in our modern world. While some people are working in labs to better understand cellular functions and how life catalyzes reactions in different environments, there are other researchers who are studying old rocks to better understand what the chemical and physical environment of the early Earth’s surface was. If we want to better understand how life may have gone from an evolving chemical system to the great diversity of living, evolving things that we see today, then we need people from a lot of different scientific backgrounds to work together to put together the pieces of the puzzle.