*as also posted
here
The history of human marriage - Google Books
In this book the author, an anthropologist, shows that throughout the animal kingdom (including primitive humans), those that are monogamous in relationships, do so for the care of the young. some animals have different ways of caring for the young, however they always include a mother and father. Homosexual activity in animals is never monogamous as the breeding and care of offspring still depend on both sexes playing a role in the care of offspring. The only animals that exhibit monogamy are exclusively male-female for the production and care of offspring.
Since SSM pundits are so adamant that we should mimic the animal kingdom [since they always bring up, "But animals do it!"]. Marriages should only be sanctioned between male and female partners for the
prospective production and care for offspring.