Final answer:
Polyandry is a culturally sanctioned form of marriage where one woman has several husbands and is observed in some societies, like in Nepal. Contrary to the student's claim, it is not merely hypothetical. It is less common than polygyny, which is more prevalent worldwide.
Step-by-step explanation:
Polyandry is not hypothetical; there are ethnographic examples of it. Polyandry is a form of marriage where one woman has multiple husbands. It is much less common than polygyny, where one man has multiple wives. One form of polyandry is fraternal polyandry, which can be seen in Nepal, where brothers share a wife. This system serves to keep land inheritance intact and minimize overpopulation in areas with scarce resources. Within these complex family structures, brothers may take turns working away from home and spending time with their shared wife, which helps in managing farmlands or herding animals scattered over various locations.
In contrast, polygyny is seen in various societies around the world and is often a sign of status, providing economic and social benefits. For instance, in some polygamous cultures in Israel and Thailand, polygamous marriages are accepted and sometimes even create greater economic opportunities for family members. However, as education and urbanization increase, the practice of polygamy is expected to decline.
This information counters the claim that polyandry is wholly hypothetical. While it is a minority practice globally, it does exist as a culturally sanctioned form of marriage in certain societies, notably less common than polygyny, but nevertheless an important aspect of cultural diversity and social organization.