FEST Writing Group

Sexual reproduction: Nature’s gift, Nature’s Challenge

work in progress by Stephanie Ferrera

“We are very different people. We just can’t communicate.”
These are words often spoken by couples in marriage counselling.

Sexual reproduction brings two “very different people” together in a partnership that has the potential to bring new life into the world, to form the foundation for a family, and to experience the deepest level of intimacy and complementarity of which humans are capable. It challenges them to work out their differences if they are to succeed in fulfilling the mission of mating and marriage. These differences are rooted in biology, economics, and culture.
Biologists have proposed that the main benefit of sexual union is that it creates genetic variation, which, in turn, gives a species the ability to adapt more quickly in an environment of fast-evolving predators and microbes. E. O. Wilson writes: “To diversify is to adapt.” (1975, 156) Sexual reproduction reduces the genetic kinship between parent and offspring by half and mates by even more. From this perspective, Wilson notes: “The inevitable result is a conflict of interest.” The male will profit more if he can inseminate additional females; the female will profit if she can retain exclusive aid from the male. He concludes: “Sex is an antisocial force in evolution.” (1975. Sociobiology. 155)
Beyond the obvious differences in the male and female roles in reproduction, partners diverge in other basic ways. Men and women are partners in bringing new life into the world, in nurturing children from infancy to maturity, and in providing the resources needed. In each dimension the male and female roles are different. The number of differences to be worked out is almost without limit.

Reproductive roles
Male-female asymmetry in reproductive roles begins at the level of the gamete. The human egg is eight-five thousand times larger than the human sperm. The female is born with the limited number of eggs she will have for life while the male produces sperm continuously by the millions. In brief: there are so many sperm chasing so few eggs. Under the heading, “mating strategy,” Wilson states that
“women have more at stake in sexual activity than men, because of the limited age span in which they can reproduce and the heavy investment required of them with each child conceived. One egg, to put the matter in elemental terms, is hugely more valuable than a single sperm, which must compete with millions of other sperm for the egg.” (1998, Consilience, 169.)

These basic facts of life place women in the ambiguous position of having higher worth, reproductively speaking, yet being at greater risk than men in the sexual relationship. It gives rise to the familiar pattern of male assertiveness and female reticence.

However, men are not without risk in the mating game. Darwin was confounded by traits, such as the peacock’s tail and the deer’s antlers that made their owners more conspicuous to predators and too clumsy to escape. These ornaments occur most often in males. How could natural selection account for traits and behaviors that risked their owner’s chances of survival? Darwin’s answer was to introduce the concept of sexual selection. In The Descent of Man and Selection in Relation to Sex (1871), he proposed that traits that are disadvantageous for survival serve a different function: reproductive success. He observed that males risk much, even their lives, to attract females and compete with other males for mating opportunities, while females are the choosers.

Applying this to our own species, we can see that human courting and mating behavior generally fits the pattern Darwin proposed: male-male competition, female choice. However, another important variable, one that distinguishes humans from most other primates, is male parental investment. Robert Wright explains:
We are, as they say in zoology literature, high in MPI. We’re not so high that male parental investment typically rivals female parental investment, but we’re a lot higher than the average primate. (Wright 1995, 57)
With this, mating becomes more of a two-way street, males competing for scarce female eggs, females competing for scarce male investment. Mark Flinn identifies conditions that favor fathers’ investment:
The advantages of intensive parenting, including paternal protection and other care, require a most unusual pattern of mating relationships: moderately exclusive pair-bonding in multiple male groups. …Paternal care is most likely to be favored by natural selection in conditions where males can identify their offspring with sufficient probability to offset the costs of investment, although reciprocity with mates is also likely to be involved. (Flinn in Noone & Papero, 2015, 148)

Parental and caregiving roles

Nature gives the female a head start in forming an attachment to the child. Physical and hormonal changes alert the woman that she has become pregnant. It is a life-changing realization that comes to her with or without her readiness for it, with or without a secure relationship with the father, and with or without sufficient resources for the care of a child.

The human infant requires quite a lot of care for quite a long time. In accord with the general mammalian pattern, gestation, childbirth, and lactation make mother the primary nurturer, but mother alone is in a vulnerable position and she will quickly turn to her partner, to her own parents, and to kin and community for help. Humans are among a small number of cooperative breeding species in which mothers enlist and trust other caretakers. (Hrdy 1999)

Bowen theory sees the mother-father-child unit as the primary triangle, situated within the larger systems of the nuclear family and the multigenerational family. The degree of engagement and cooperation that parents have with their own families of origin as well as other resources becomes of utmost importance when it comes to raising children.
The importance of the connection between the attachment and bonding between mates and the father’s care of his children is emphasized in the literature on mating and childrearing. However, while fathers may defer to mothers, especially in the care of infants, most show intense interest in their children, motivation to provide for them, and an ability to form a relationship with the child independently of mother. Sarah Hrdy reports a study that measured the responses of new fathers and mothers to infant distress signals. She writes:

At the first signal of real distress, both mothers and fathers responded with equal alacrity. But if the infant merely sounded uncomfortable, but not in extremis…the mother was the quicker to respond. (Hrdy 1999, 212)
She makes the interesting observation that “this seemingly insignificant difference in thresholds for responding to infant cues” can easily convert into differences in the way mothers and fathers behave, be repeatedly reinforced by mothers stepping up more quickly than fathers, and lead to “a marked division of labor by sex.” (213) The lesson to be taken is that if mothers can take a step back, and fathers a step up, they can become a more equal, reciprocal team in raising their child.

Topics for research and thinking:

Economic roles of men and women as they have evolved over changing economic conditions
Systems that seem to exaggerate the differences between the sexes: polygyny, patriarchy
The challenge of regulating reproduction, balancing population with resources.
How Bowen theory is a framework that addresses all of the above.