What we observe is a world where the details matter. But evolution is a theory of serendipity. For example, it is beyond all odds that proteins would arise by chance, but this is only the beginning of evolution’s difficulties. The gene encoding the protein needs to be expressed at the right times, the resulting protein needs to be produced in the right quantities, it then needs to be transported to the right place in the cell, and so forth.
Here’s one study showing the intricacies not of a protein’s design, but of its distribution. In this case the concentration of a multi-purpose protein called cohesin within the cell is crucial.
Cohesin is involved in such tasks as chromosome condensation, segregation and cohesion, and DNA repair. But the concentration of cohesin required to perform these different tasks differs substantially. And if the concentration levels go wrong then some of the cell functions can fail while others may continue to work properly:
The requirement for different in vivo cohesin concentrations to achieve distinct cohesin functions provides an explanation for how cohesin mutations can specifically lead to adult disorders such as Cornelia de Lange Syndrome and Roberts Syndrome without compromising the cell divisions needed for development and maturation.
In biology, the details matter. Proteins do not merely evolve by chance and then suddenly begin solving problems. An army of other molecular machines need to sense the need for the protein, access the associated gene, open it up and make a copy, use the copy to construct the protein, construct the right quantity, transport the protein to the right place in the cell and in the right concentration, and destroy the protein when the job is done.
Could all of this have evolved by chance? I don’t know, perhaps. But that is not what science is telling us.