From page 306 of “Darwin’s Ghost” by Steve Jones.
“Given all this emphasis on efficiency, it is a surprise to find great tracts of repetition and decay within the DNA. There are not just thousands of repeats of the same message, but hundreds of delaiadated ruins of what once were working genes. Such pseudogenes, as they are known, are everywhere, in mammals at least. The hemoglobin gene family has half a dozen, each corrupted almost beyond recognition. Long ago, a mutation destroyed the switch that turns the gene on, or inserted an instruction that it should stop doing its job, or damaged its ability to edit its message. Some pseudogenes are the remnants of viral attack and have been read back into the DNA from an edited version of the genetic message to be scattered where they fall. Evolution at once lost interest; as soon as the gene stopped work it was, in effect, invisible. Such structures sit for millions of years and crumble until thier shape can barely be discerned.
Yep, that’s the evolutionary philosophy I’m talking about.