There are many characteristics of the DNA code that make it very sophisticated. Some evolutionists claim that natural selection can explain how the DNA language became optimized. However, the idea that mutations could produce a new workable code is absurd. Like changing the position of some of the keys on a computer keyboard. Without a simultaneous change in the software associating the keys with the letters, numerous words would be misspelt. This led the co-discoverer of the DNA structure, Francis Crick, to argue that, once in place, the DNA code would be frozen as it would be very difficult, if not impossible to change.