The idea that some groups of people may be more intelligent than others is one of those hypotheses that dare not speak its name. But Gregory Cochran is 1 to say it anyway. He is that 2 bird, a scientist who works independently 3 any institution. He helped popularize the idea that some diseases not 4 thought to have a bacterial cause were actually infections, which aroused Much controversy when it was first suggested.
5 he, however, might tremble at the 6 of what he is about to do. Together with another two scientists, he is publishing a paper which not only 7 that one group of humanity is more intelligent than the others, but explains the process that has brought this about. The group in 8 are a particular people originated from central Europe. The process is natural selection.
This group generally do well in IQ test, 9 12-15 points above the 10 value of 100, and have contributed 11 to the intellectual and cultural life of the West, as the 12 of their elites, including several world-renowned scientists, 13 . They also suffer more often than most people from a number of nasty genetic diseases, such as breast cancer. These facts, 14 , have previously been thought unrelated. The former has been 15 to social effects, such as a strong tradition of 16 education. The latter was seen as a （an） 17 of genetic isolation. Dr. Cochran suggests that the intelligence and diseases are intimately 18 . His argument is that the unusual history of these people has 19 them to unique evolutionary pressures that have resulted in this 20 state of affairs.