Age of Menarche in Mexico. The average age has been decreasing which is typical of developing nations. Of note are urban "non-indigenous" (i.e. admixed with African DNA) women reaching menarche the soonest, in keeping with r/K theory. Similarly, non-admixed indigenous ruralite women have retained the highest age at menarche, which corresponds with their ancestral population (Ancient Mongoloids ~10kA ago). SES is most likely a proxy for nutrition in Mexico.

Topic: menarche
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