Earlier (and perhaps more impactful) research in this area: http://www.jstor.org/discover/10.2307/2744104?uid=3739936&uid=2129&uid=2&uid=70&uid=4&uid=3739256&si

Earlier (and perhaps more impactful) research in this area: http://www.jstor.org/discover/10.2307/2744104?uid=3739936&uid=2129&uid=2&uid=70&uid=4&uid=3739256&sid=21101366545563 http://www.jstor.org/discover/10.2307/2744104?uid=3739936&#3... The tradeoff between digestion and cognition suggests that adaptations are rarely cost neutral, and explains why random traits don't just improve forever. (ie, why we don't all have eyes like hawks).