I often hear “mutation can’t create anything new, only damage” as a criticism of genetic mechanisms that supply variation in organisms. It’s not true, since there are so many mutations that some of them are immediately useful. But another mechanism of variation is gene duplication. Once you have two identical genes (“No new information,” chant the creationists), one of them is free to change into something else. It’s like hiring two waiters. Both of them may have the same job description, but one can take orders while the other fetches them, or lays tables, or ushers people to their seats.
I want creationists to imagine one of those children’s activity tables where organizers pass out photocopied line drawings to be coloured. Do they imagine that all those duplicated sheets end up the same after the children are finished? Don’t they remember the walls of multi-coloured art based on the same picture? What makes them think evolution can’t do the same with duplicate genes? It is wilful stupidity.