The Jupiter Theft

was warm and dry to the touch. It writhed and contracted in his palm, its threadlike legs clinging.

Triad made a faint wheezing sound. The others looked at Jameson with incomprehension or revulsion, except for Dmitri, whose face was expectant.

“This isn’t a parasite,” Jameson told them. “It’s the other half of the Cygnan race.”

“A parasitic male!” Dmitri said, turning the squirming creature over in his hand. “Of course! Why didn’t I think of it?”

Over at the sloping wall, a few of the braver young men were restraining Triad, who was making weak, uncoordinated attempts to get to Jameson and Dmitri. Most of the diminished human colony was there, including Janet Lemieux, who had left a sedated Boyle in the care of a couple of volunteers. Ruiz had already regained consciousness with the help of a stimulant she’d given him, and though he hadn’t yet tried to sit up, he was watching with lively interest.

“The Cygnans are all females,” Jameson said. “The ones we’ve been thinking of as Cygnans, I mean. What fooled me was the way they behave like courting couples. And the personality differences, and the fact that one was bigger and stronger than the other. If they’ve got to pair off to reproduce, I suppose it’s natural that a weaker would tend to gravitate toward a stronger.”

Dmitri nodded in agreement. “Not only natural—it’s a survival mechanism for the species.”

“What are you two talking about?” Liz cried plaintively.

Dmitri laughed with sheer enjoyment. “These little males are just nonsentient vegetables,” he said. “The Cygnans exchange them like engagement rings. Why didn’t I see it? It took a rocket jockey like Tod here to point it out to me.”

“But that thing in your hand doesn’t look anything like a Cygnan,” Omar objected. “It’s more like an insect.”

“Ah, but it does!” Dmitri said. “Same body structure—but the legs have atrophied because it needs them only for clinging, and the ‘head’ has regressed to its only function: to suck blood. No eyes, because a parasite doesn’t need them, and if I dissected it I would find no digestive organs, because it gets its meals predigested. But the gonads, you can be sure, are well developed, as they are in all parasites. It is perfectly adapted to its way of life.”

“What a filthy thing!” Beth said.

“Filthy?” Dmitri said, in genuine puzzlement. “Perhaps to us. To the Cygnans, perfectly natural. Nature always provides rewards to encourage reproduction—rewards in the form of pleasure, or at least release from compulsion.” He nodded toward the struggling Triad, whose body contractions had grown rhythmic and violent. “That poor creature is in torment.”

“But a parasitic mate!” Liz said. “Isn’t that a bit farfetched?”

“There are any number of terrestrial examples,” Dmitri said. “Trichosomoides crassicauda. It’s a parasitic worm, like the Cygnans’ distant ancestors. The male lives as a parasite within the uterus of its own mate. Edryolychnus. It’s a deep-sea fish, very ugly. The male’s a tiny appendage that attaches itself to the female early in life. Its eyes and other sense organs atrophy. Its blood vessels fuse with hers. I could go on.”

“Strange way to perpetuate a species,” Omar said.

“No stranger than ours. Males aren’t very important in the scheme of things. They’re just a mechanism for exchanging gametes. Female spiders eat their mates when they’ve finished their job. This thing in my hand is a gene package, not a lover. A Cygnan’s emotional equivalent of a mate is the other female she trades males with.”

Jameson became thoughtful. “Dmitri, how would it work biologically?”

Dmitri looked around happily. “There’s an almost precise, terrestrial analogy. A mite that’s parasitic on moths: Lasioseius lacunosus. About one egg in twenty hatches as a male. The male is born first. That’s so it can be an obstetrician for its sisters. It helps in the birth of the females by pulling them out of the mother’s body. It lives as an ecoparasite with the mother for a brief time—it can’t survive removal itself. But before its sisters leave home, it impregnates them.”

“But the Cygnan male doesn’t impregnate its own sister?” Jameson said.

“No, it simply becomes a parasite on her. Let’s say it works like this. Suppose the Cygnans have multiple births, or hatchings, or buddings, or whatever. The male can’t survive on its own, any more than Lasioseius lacunosus can. It must immediately hook itself into the bloodstream of one of its much larger sisters or die. The attachment of a first male probably stimulates production of a hormone or chemical trigger that prevents the other male siblings from implanting themselves—”

“The way an ovum becomes impervious to other sperm after the first one reaches it,” Janet said, looking up from her work of bandaging Ruiz’s head.

“Yes, yes,” Dmitri said impatiently. “At any rate, it’s the fittest that tend to survive.”

“The courtship mechanism…” Jameson prompted.

Dmitri nodded. “What you call ‘courtship’ is two females pairing of and eventually exchanging their parasitic males. It must be as charged with emotion for them as sex is for humans. The exchange is an evolutionary survival mechanism which prevents inbreeding. Presumably there’s a hormone or body-chemistry block which ordinarily prevents a parasite from impregnating its sister-host. The courtship ritual, on the other hand, must release pheromones—repare the endocrine systems of both the hosts and the parasites to accept the switch, just as a foreplay prepares both human sexes for sex.”

Jameson’s eyes strayed toward Triad. The involuntary contractions of her body looked as if they were causing her physical pain. With each wave her rubbery body compressed by a third, then stretched out again like taffy. He was unable to imagine what she was feeling but clearly she was in the grip of a powerful biological imperative.

Her own tiny brother was already within the body of the dead Tetrachord, presumably dead or dying itself. The other half of the exchange must have been interrupted by the alarm. The squirming thing in Dmitri’s hand was animated by its own biological imperative. If it failed to make contact with Triad soon, then the union of Tetrachord and Triad would produce no young.

Did Cygnans mate for life?

One of the Struggle Brigade stalwarts, a sinewy fellow with close-set eyes and bristly black hair brushed forward over his forehead, had retrieved the hoe and was prodding Triad with the handle. Jameson reached him in three swift strides.

“Stop that!” he said, and snatched the hoe from the startled man. He tossed it down the slope as far as he could throw it. The Cygnan, in her private misery, shuddered. The sounds she was making were nonhuman, but to Jameson’s acclimatized ears they were piteous nevertheless.

Hating himself for what he was doing, he got down on one knee and said, in his broken-chord Cygnanese, “Triad, I talk. Do you hear?”

Dmitri broke off his lecture. He started forward. “Stay where you are,” Jameson said sharply. Dmitri stopped. The other people fell silent and watched Jameson.

The clustered eye polyps quivered and stretched in Jameson’s direction. It was like looking into three orange-rimmed inkwells.

“I hear, Ja-me-son,” the Cygnan trilled. “Give me the little brother.”

“Not yet. You must help me leave this place.”

“Jameson and his sisters are a wrongness in the sight of the mother-within-herself. You have stopped Tetrachord at the time of her (?)”

Jameson didn’t recognize the last ideogram, but Triad, despite her distress, had made an effort to put the rest of her message in terms he could understand. “Stopped” was the term for a damaged piece of machinery. “Wrongness” was the word for “mistake” that had cropped up so frequently during his language lessons.

“What is she saying?” Dmitri asked eagerly.

“She’s saying that we’re abominations in the sight of her deity because we murdered her mate,” Jameson said.

Beth made an indignant noise. “What about the people they killed? And the Jovians and the other life forms they’ve exterminated? I suppose that if we don’t have six legs, we don’t count!”

“No,” Jameson said. “We don’t.” He turned back to Triad. “The sisters who … stopped … Tetrachord are a wrongness to Jameson and his other sisters too.”