Medical advances have improved the quality and length of life for countless people around the world. While this is obviously a positive thing, human evolution changes if Darwin’s nature has less impact and Hippocrates’s modern medicine grows. For example, scientists in Austria say that the rise in Caesarean section births has helped the shape of women to evolve.
The researchers estimate that the number of babies that cannot fit down a woman’s birth canal has gone from 3 percent in 1960 to 3.6 percent today. Their explanation is that there have been a few generations of women who have a narrow pelvis size (and smaller birth canal) that have had babies via c-section. The idea being that women with a narrow pelvis would have died in childbirth more often, thus not passing the thin pelvis gene on to descendants.
“Without modern medical intervention such problems often were lethal and this is, from an evolutionary perspective, selection,” said Dr Philipp Mitteroecker, of the department of theoretical biology at the University of Vienna, in a story by bbc.com. The original research was published in the in the journal, Proceedings of the National Academy of Sciences.