William Tenn - Venus and the Seven Sexes

“Variation? You mean so your children would be different?”

“Exactly. You see, there is only one thing that all the ravening life-forms of Venus would rather eat than each other; and that one thing is a Plookh. From the other continent, from all the islands and seas of Venus they come at different times for their Plookh feed. When a Plookh is discovered, a normally herbivorous animal will battle a mighty carnivore to the death and disregard the carcass of its defeated opponent—to enjoy the Plookh.”

Our civilizer considered me with a good deal of interest. “Why—what have you got that no one else has got?”

“We don’t know—exactly. It may be that our bodies possess a flavor that is uniformly exciting to all Venusian palates; it may be, as one of the biologists suggested to nzred fanobrel, that our tissue contains an element—a vitamin—essential to the diet of all the life-forms of our planet. But we are small and helpless creatures who must reproduce in quantity if we are to survive. And a large part of that quantity must differ from the parent who himself has survived into the reproductive stage. Thus, with seven parents who have lived long enough to reproduce, the offspring inherits the maximum qualities of survival as well as enough variation from any given parent to insure a constantly and rapidly improving race of Plookh.”

An affirmative grunt. “That would be it. In the one-sex stage— asexual is what the bio professors call it—it’s almost impossible to have varied offspring. In the bisexual stage, you get a good deal of variation. And with seven sexes, the sky must be the limit. But don’t you ever get a Plookh who isn’t good to eat, or who can maybe fight his way out of a jam?”

“No. It would seem that whatever makes us delicious is essential to our own physical structure. And, according to the biologists of the expedition again, our evolutionary accent has always been on evasiveness—whether by nimbleness, protective coloration or ability to hide—so that we have never developed a belligerent Plookh. We have never been able to: it is not as if we had only one or two enemies. All who are not Plookh will eat Plookhh. Except humans—and may I take this occasion to express our deep gratitude?

“From time to time, our Books of Numbers tell us, Plookh have formed communities and attempted to resist extermination by united effort. In vain; they merely disappeared in groups instead of individually. We never had the time to perfect a workable system of defense, to devise such splendid things as weapons—which we understand humans have. That is why we rejoiced so at your coming. At last—”

“Save the pats on the back. I’m here to do a job, to make a stereo that will be at least an epic, even if I don’t have the raw material of a saga. Give me a line on how all this works.”

“May I say that whether it is an epic or a saga, we will still be grateful and sing the greatness of your name forever? Just so we are set on the path of civilization; just so we learn to construct impregnable dwellings and—”

“Sure. Sure. Wait till I get me a fresh bottle. Now—what are your seven sexes and how do you go about making families?”

I reflected carefully. I knew full well what a responsibility was mine at that moment; how important it was that I give our benefactor completely accurate information to aid him in the making of stereos, the first step we must take toward civilization.

“Please understand that much of this is beyond our ken. We know what seems to happen, but for an explanation we use the theories of the first flame ship’s biologists. Unfortunately, their theories were multiple and couched in human terms which even they admitted were somewhat elementary when applied to the process of Plookh reproduction. We sacrificed a whole generation of the fanobrel family for microscopic experimentation and only a broad outline was worked out. Our seven sexes are—”

“I heard it was complicated,” Shlestertrap interrupted. “The biologists left five miles of figures in the Venusian Section of the Interplanetary Cultural Mission after they returned from this expedition. You see, there was an election right after that: a new party came in and fired them. I wasn’t going to wade through all that scientific junk, no sir! One of them—Gogarty, I think—pulled every wire there was to take this job away from me and come here in my place. Some people just can’t stand being out after they’ve been politically in for so long. Me, I’m here to make stereos—good ones. I’m here to do just what the prospectus of the Venusian Section called for—’bring culture to the Plookhh as per request.’ ”

“Thank you. We did wonder why the Gogarty—pardon—why Gogarty didn’t return; he expressed such an enormous interest in our ways and welfare. But no doubt the operation of firing him by the new party after the election was far more productive in the human scheme of things. We have not yet advanced to the state of parties and elections or any such tools. To us one human is as omniscient and magnificent as the other. Of course, you understand all relevant data on human genetics?”

“Sure. You mean chromosomes and stuff?”

I flapped my small tentacle eagerly. “Yes, chromosomes and stuff. Especially stuff. I think it is the part about ‘stuff’ that has made the whole subject somewhat difficult for us. Gogarty never mentioned it. All he discussed were chromosomes and genes.”

“No wonder I got such a crash bio briefing! Let’s see. Chromosomes are collections of genes which in turn control characteristics. When an animal is ready to reproduce, its germ-cells—or reproductive cells—each divide into two daughter cells called gametes, each daughter cell possessing one-half the chromosomes of the parent cell, every chromosome in each gamete corresponding to an opposite number chromosome in the other. Process is called meiosis. Correct me if I’m wrong anywhere.”

“And how can a human be wrong?” I asked devoutly.

His face wrinkled. “In the case of humans, the female germ-cell has twenty-four pairs of chromosomes, one pair being known as the X chromosome and determining sex. It splits into two female gametes of twenty-four corresponding chromosomes, one X chromosome in each gamete. Since the male germ-cell—if I remember rightly—has only twenty-three identical pairs of chromosomes and an additional unmatched pair called the X-Y chromosome, it divides into two male gametes of twenty-four chromosomes each, of which only twenty-three have a twin in each gamete; the twenty-fourth being the X chromosome in one male gamete and the Y chromosome in the other. If a male gamete—or sperm-cell—containing an X chromosome unites with a female gamete—ovum, or egg-cell, the briefing guy called it—carrying an X chromosome, the resultant zygote will be female; but if the Y chromosome gamete fertilizes the ovum, you have a male zygote. They really jammed that stuff in me before they let me leave Earth. Lectures, sleep-sessions, the whole bit.”

“Exactly,” I said enthusiastically. “Now in our case—”

“I recall something else, come to think of it. The Y is supposed to be a slightly undeveloped or retarded chromosome and it makes the gamete containing it a little weaker or something. The sperm-cell with the X chromosome is faster and stronger and has a better chance of fertilizing the ovum. It also shows why women can take it better than men and live longer. Simple. How’s it work with you?”

The extended conversation was making me giddy, and the atmosphere of the dome—with its small vapor content—dried my faculties. However, this was a historic occasion: no personal weakness must be allowed to interfere. I stiffened my tentacles and began.