I recently read an article in Scientific American,it was given that the laws of physics will prevent the human brain from becoming an even more powerful thinking machine,i would like to know how do the researchers predict about the human brain's evolutionary limit when we are one of the most recently evolved organisms. i also read about the inefficiencies in the brain caused due to it's size(elephant's). the brains of large mammals were compared to old hollow chested grandfather clocks and the brains of small flying insects were compared to exquisite pocket watches. Evolution has come across many problems before,why is it not possible for evolution to come up with more compact and efficient version of the human brain?,is it not possible for evolution to increase the density of the brain without increasing it's size by squeezing more neurons per unit volume? Modern generation of human beings are putting more pressure on their brains compared to their previous generations,we are trying to understand more complex phenomenon in nature and concepts in science and technology than our previous generations,scientific knowledge is expanding exponentially and we are trying to stuff all that into our brains to some extent atleast,does this not result in slight modifications in the human brain after some generations to increase the capacity?