IMHO, calling the brain amazing, complicated, etc, is all good... but "efficient" to me goes basically in direct contradiction with the basic layman's view of evolution. Zillions of mistakes after mistakes - the more complicated life gets, the more are kept that didn't improve reproduction. We're just a <b>huge hoard</b> of mistakes, but just happen to be the ones that got this this far by getting more useful for reproduction than all the other lines that didn't get this far.