Sex Determination

A Third Sex?

If two mating types are good, would more be better? Could different "types" of human, other than male or female, serve unimaginable functions? Could machines fill the social as well as biological functions of sexual partners?

Dawn, by Octavia Butler (1987)

Written late in the Cold War, this story assumes that a nuclear war has devastated the planet, making it uninhabitable by humans. Only a few humans have been "rescued," kept alive by an alien race, the Oankali. The Oankali need human beings as a source of genetic diversity. They have a unique reproductive cycle involving a third sex, the ooloi. When an Oankali male and female combine their germ cells, the ooloi participates in the mating by a natural form of genetic engineering that ensures that the best or "most fit" genetic combinations occur. Thus, unlike traditional sexual exchange that generates random recombinations, Oankali mating tends to reverse genetic diversity by singling out optimal genetic combinations and eliminating poor ones. But such a mechanism leads the Oankali down an evolutionary dead end, leaving them vulnerable to environmental change. The only way out of the dead end is for Oankali populations periodically to embrace alien species, taking in their genetic diversity to regenerate Oankali diversity.

Discussion Questions:

1. What evidence do Oankali exhibit of their "genetic trade" with other species? Which of their traits come from previous alien species with whom they have interbred? What genetic traits do they hope to obtain from humans?

2. The Oankali claim that their "trade" with humans is an equal exchange because the human participants, and their alien descendants, will obtain enhanced biological powers, as well as escape the cycle of violence that leads to nuclear war. The humans object that the trade is forced on them and that their descendants will no longer be human. Who do you think is right?

3. Do you think it's likely that something like the ooloi could evolve as a third sex? What would be the biological advantages and disadvantages of such a system compared with traditional sexual reproduction?

Brain Plague, by Joan Slonczewski (2000)

In the distant future, human sexuality has become largely separated from physical reproduction. Humans are male or female, but most exhibit bisexual attraction. They even respond sexually to "sentient machines," which define themselves as male or female. Meanwhile, intelligent microbes, called "micros," inhabit human brains. Beneficial micros communicate with their hosts, enhancing human brainpower; virulent micros take over the brain, causing addictive symptoms and death. Micros are unisexual, and their own reproductive strategies are typical of microbes. Micro "children" reproduce by "merging" with each other to recombine their circular genomes directly, and then they come apart and divide. A few exceptional children stop merging and become "elders" who do not reproduce but live to a great age (like "viable but unculturable" microbes.)

Discussion Questions:

1. Do you agree with the assumption that as human sex roles become more similar, bisexuality will become the social norm? Why do you think the characters in this story—even sentient machines—maintain male or female sexual identity despite the total equivalence of sex roles?

2. In the micro society, "children" are completely sexualized, existing only to merge and reproduce, whereas the few "elders" are asexual. How does this affect social constructions of what is "proper"—for example, what constitutes art and pornography?

3. How does the micro life cycle compare with actual life cycles of bacteria and protists? What are the advantages of systems that generate nonreproducing forms of cells or long-lived forms such as spores or biofilms?

Halfway Human, by Carolyn Ives Gilman (1998)

On the isolated planet Gammadis, all children are born with indeterminate sex. In adolescence, they develop into male, female, or "bland," an individual totally lacking sexual physical characteristics. Blands are treated as servants, a lower class of beings considered "halfway human." During the course of the story, investigators discover that the Gammadis society actually treats its own children with hormones, deliberately converting a proportion of them into blands as a form of population control.

Discussion Questions:

1. While the Gammadians claim to forbid sexual contact with blands, in practice they actually use blands for sexual slavery. Does it make sense that this would happen? How does this cultural phenomenon compare with the historical experience of slavery in America?

2. Does the bland protagonist seem more male or more female, or neither? How do we define what is "male" or "female" in the absence of reproductive potential? Is it possible to think of an individual as human without being male or female?

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