Evolution can destroy design - as well as create it

Susan Blackmore has many good memes - as well as a few more dubious ones. In her recent description of her experience lecturing on memes in Oxford (recounted in A hundred walked out of my lecture), there was one of the more dubious ones. Susan said this:

I persevered, trying to put over the idea that evolution is inevitable – if you have information that is copied with variation and selection then you must get (as Dan Dennett p50 puts it) ‘Design out of chaos without the aid of mind’. It is this inevitability that I find so delightful – the evolutionary algorithm just must produce design, and once you understand that you have no need to believe or not believe in evolution.

She presented the same idea at TED. The problem with the idea is devolution. In a nutshell, whether evolution results in the accumulation or the destruction of design depends a lot on the mutation rate. In a sufficiently hostile and mutation-rich environment, living systems do not undergo cumulative adaptive evolution - instead they exhibit devolution - progressive loss of function, possibly culminating in eventual extinction. It isn't really very accurate to say that "evolutionary algorithm just must produce design". It can also destroy and extinguish all appearance of "design" - and often does so, in hostile environments.

If evolution only created design, living systems would have a rosy future. As it is, they could easily be wiped out by a stray solar mass. Evolution can destroy - as well as create.