Dataset.csv from Human variation in the shape of the birth canal is significant and geographically structured

The human birth canal shows a tight fit with the size of the neonate, which can lead to obstetric complications. This is not the case in other apes, and has been explained as the outcome of conflicting evolutionary pressures for bipedal locomotion and parturition of a highly encephalized fetus. Despite the suggested evolutionary constraints on the female pelvis, we show that women are, in fact, extremely variable in the shape of the bony birth canal, with human populations having differently shaped pelvic canals. Neutral evolution through genetic drift and differential migration are largely responsible for the observed pattern of morphological diversity, which correlates well with neutral genetic diversity. Climatic adaptation might have played a role, albeit a minor one, with populations from colder regions showing a more transversally oval shape of the canal inlet. The significant extent of canal shape variation among women from different regions of the world has important implications for modern obstetric practice in multi-ethnic societies, as modern medical understanding has been largely developed on studies of European women.

人类产道与新生儿体型的适配性极强，可引发产科并发症（obstetric complications）。这一现象在其他类人猿中并未出现，其被归因于两足行走（bipedal locomotion）与高脑化胎儿分娩（parturition of a highly encephalized fetus）之间相互冲突的进化压力。尽管学界认为女性骨盆存在此类进化约束，我们的研究却证实，女性骨性产道（bony birth canal）的形状存在极大变异，不同人类人群的骨盆产道形态各不相同。遗传漂变（genetic drift）与差异化迁移（differential migration）介导的中性进化，是观测到的形态多样性模式的主要成因，该模式与中性遗传多样性（neutral genetic diversity）的相关性良好。气候适应（climatic adaptation）或许也发挥了一定作用（尽管影响相对较小）：来自寒冷地区的人群，其产道入口更呈横椭圆形。全球不同地区女性的产道形状存在显著变异，这对多民族社会的现代产科实践具有重要意义，因为当前主流的医学认知大多基于对欧洲女性的研究。