A role model is a person whose roles can be modelled. If the roles you conceive and give birth to today cannot be adopted by anyone in your absence, you are no good model.

Among other possibilities, money was invented to make it possible for a foolish man to control wise men; a weak man, strong men; a child, old men; an ignorant man, knowledgeable men; and for a dwarf to control giants.

The metaphor is so obvious. Easter Island isolated in the Pacific Ocean _ once the island got into trouble, there was no way they could get free. There was no other people from whom they could get help. In the same way that we on Planet Earth, if we ruin our own [world], we won't be able to get help.

But Nita had always seen having a child as selfish. Why bring another soul into this world, she'd say, when there are so many out there that need our help?

The daddy-at-home theory posits that concealed ovulation evolved to promote monogamy, to force the man to stay home, and thus to bolster his certainty about his paternity of his wife's children. The many-fathers theory instead posits that concealed ovulation evolved to give the women access to many sex partners and thus to leave many men uncertain as to whether they sired her children.

But the largest number of primate species--thirty-four--have a promiscuous system in which females routinely associate and copulate with multiple males.