Fossils of biochemistry evolution- still in dna tree of life - in our dna. Anthropic principle the world is so perfect for us that it could have not happened by chance. World was change by geological, cosmological and biological evolution (1988 barrow and tipler) We can take 2 amino acids and we can polymerize them - peptide bond. Range of di erent r group and rotation of peptide bond - gives speci city to protein. Binding and catalysis is enhanced by protein polymers then nucleic acid polymers. Hydrophobic places interior of protein or membrane - away from the solvent. Epitopes pick most hydrophilic regions - peaks just get amino acid sequences for the peaks. They are a primary sequence of nucleotides/nucleic acids is under selection. Then, what is under selection is a primary sequence of amino acids. Protein goes into all kinds of shapes, and it falls into energy trophs. The bottom shape is usually the preferred and stable shape.