The Limits of Intelligence (pdf)
This article argues that since anatomically modern human (Homo sapiens sapiens) brains cost an extremely high amount of energy to maintain, we as a species may have reached close to the pinnacle of our cognitive evolution. In other words, we're probably as smart as we'll ever be; we can't evolve significantly greater intelligence. This made me wonder about all the elves, aliens, and other fictional races in speculative fiction that are purported to be smarter than humans. If these races are the product of evolution by natural selection like ourselves, they may not be evolutionarily realistic. Of course this won't deter fantasy worldbuilders who eschew science altogether, but I think this is worth considering for those of us who prefer some degree of biological realism in our fantasy.
Your thoughts on this?