According to Erika DeBenedictis, “one of the big limitations of biology are the basic building blocks themselves.”
I will begin with an example from embryology, then turn to metabolism, and finish with the breadth of chemical space covered by the natural amino acids.
Paleontologist George Gaylord Simpson once declared that “man is the result of a purposeless and natural process that did not have him in mind.”
For our biochemistry geeks, one mug contains both the periodic table of elements and a DNA-amino acids codon wheel.
Twenty elements — and water, too — appear to have been precisely fine-tuned in advance for highly specific biochemical roles.