A further thought on the economic basis of gender inequality among the Selk'nam of Tierra del Fuego:

The Hain ceremony involved the men retreating to a lodge, where they would dress up as the demon Shoort and go out to terrorize the women (according to the myth that only the men knew, the women used to do this very thing to the men constantly, extorting food from the men through fear). The Hain was not held regularly, because it was a long ceremony and reguired withdrawing the band's food providers from their hunting duties. So it would be held opportunistically, whenever the band happened upon a large food source such as a beached whale. So the whale could be seen as a necessary condition enabling the Hain.

On the other hand, it seems that the Hain could be seen as a reaction to finding a whale. The presence of a food source not obtained through male hunting would seem to threaten the economic base of the patriarchy for as long as the food lasted -- women weren't dependent on men to hack off a piece of blubber. So the men would respond by staging an ideological ploy for reinforcing their power, to make up for their economic vulnerability. You could call the myth of men upsetting the ancient women's Hain a projection of what the men feared the women would do if they knew enough and had the resources. Note that during the time of the anicent women's Hain, hunter men were the sole food providers, analagous to women's access to food from the beached whale during the modern men's Hain.