Archive for 2010/02/17

Survival of the fittest does not mean designing the smartest of solutions

2010/02/17 1 comment

Having followed my husband’s, Anders Hesselbom’s and Marcus Ahnve’s discussion about the evolution saying of “survival of the fittest” and it’s baring on software development, I want to clarify some misunderstandings concerning “survival of the fittest”.

Many believe that survival of the fittest equals the winning of the best solution. The best and the strongest survives the competition. But that is not what survival of the fittest mean in software development.

Look at the vagus nerve in a human. It starts up in the brain, goes down under the aortic arch and then back up to the throat. Is this the most elegant possible solution to building that nerve? No, only an idiot would design the nerve like this if he started from scratch. A person on which the nerve goes directly would probably be considered as better or stronger. If you consider that the same type of problem of the rerouted nerve exists in for example giraffes, you can see the extent of the problem.


So, what is survival of the fittest? When the ancestors way back in time lacked our long necks, one or a number of individuals mutated so that their necks became slightly longer. The nerve became a tiny bit longer too, but the upside of the longer neck was bigger, so the group with the neck survived long enough to reproduce in greater amount than those without it. And step by step, the necks became longer. The side effect of the elongated nerve was always a lesser disadvantage than the longer neck. Of course, after many generations we had that absurd situation we find today, but the chance that a mutation surfaced where the nerve was instead directly routed and the rerouting was successful is very slim. And since the nerve as is does not result in an enough big disadvantage in reproduction, the design remains.

If you’re a software developer, close your eyes and relax. Then think about which system and which code the solution of the vagus nerve remind you off. Is it that neat and beautiful solution you’re so proud of? Well, I hope not. It is probably some kind of legacy code or legacy system. It was probably a good solution way back, when someone made a quick and dirty solution to a simple problem. The solution was just temporary, but remained and steadily became a bigger and bigger headache.

What you really would want is to cut that nerve, rebuild it in a smarter and more future safe way. But your manager might not see it as a problem. It works, doesn’t it? Which are the risks with cutting the nerve? Are you sure that we will survive and that things will be better afterwards?

Evolution is The Greatest Show on Earth. Wonderful to see, amazing when it comes to giving birth to amazing solutions, but don’t be so sure that you have the nicest and best design.

Categories: Agile, Architecture, lean