What was the main contribution of Miller and Urey's experiment in relation to the origin of life?

The main contribution of Miller and Urey's experiment was the demonstration of how organic compounds, specifically amino acids, could be synthesized under conditions thought to resemble those of the early Earth. Their famous experiment used a mixture of gases (methane, ammonia, hydrogen, and water vapor) and subjected them to electrical sparks to simulate lightning. The results showed that within just a week, several amino acids had formed, which are essential building blocks of proteins and crucial for the formation of life.

This finding is significant because it provided insight into possible biochemical pathways that could lead to the emergence of life from non-living materials. Prior to this experiment, the origin of life was largely hypothetical, and Miller and Urey's work offered experimental evidence supporting the idea that the fundamental components of life could arise spontaneously under suitable conditions. Thus, their experiment played a key role in shaping our understanding of biogenesis and the origins of living organisms on Earth.