Imagine a small island in the ocean. On that island is a type of beetle that can fly. But, one day, there's a mutation in one of them that corrupts the genetic information that codes for the creature's wings, so that particular
one, and all of its offspring, are flightless. One day a hurricane comes through, and the beetles that can fly take to the air to try to escape, but they're all blown into the sea and they drown. The beetles that cannot fly because of the mutation try to hide in the grass or perhaps under a rock. So, the flightless beetles thrive and repopulate the island.
So...what happened? It can be said that the mutation was beneficial to the creature because it helped it to survive. While that's true, look what really happened. Information was lost! -- in this case, information that allowed the beetle to fly. The creature is now simpler, not more complex!
Darwinian evolution demands that mutations add to the code, making it more complex. But all observed mutations do is remove code, or corrupt it. So, while some mutations might serve some sort of benefit, they do not, and cannot, help Darwin!
