(N/A) In $1953$,an American scientist named $S$. $L$. Miller created conditions in a laboratory similar to the primitive atmosphere of the Earth. He mixed $CH_4, H_2, NH_3$,and water vapor in a closed flask at $800\,^oC$ and created an electric discharge using electrodes.
He observed that amino acids were formed in the mixture. Similar results were observed in experiments conducted by other scientists,where sugars,nitrogen bases,pigments,and fats were also formed.
Analysis of meteorites falling on Earth also reveals the presence of such compounds,suggesting that similar processes might be occurring in space. With such limited evidence,the theory of chemical evolution is accepted to a greater or lesser extent as the primary hypothesis.