Human beings are obsessed with sex which is why, I suppose, there are over 6 billion of us and the number continues to grow in spite of the enormous strain we are putting on our planet’s resources. Moreover, we are fascinated by sex that is a departure from the norm (if there is such a thing–I think generally it just means that we haven’t tried it yet) and the creatures of the worlds of water provide us with much to be fascinated about. In fact, those who delight in expressing moral outrage over such departures from the “norm” will have an absolute field day when they come to see what’s going on underneath the surfaces of those placid ponds or tempestuous seas or even inside certain organisms.

A number of modern biologists have taken an almost mechanistic view of sex and regard it as a series of strategies which have evolved to ensure the perpetuation of genes and a secondary set of strategies to assure dominance of a specific set of genes and, if possible, weaken or eliminate competitors. Just think of it: this vast complex of trillions of cells that constitute you as a human being may be nothing more than a highly sophisticated means of assuring the survival of some microscopic entities–a humbling thought!

Let’s start at a fairly basic level–much further down the phylogenetic tree than “muskrat love”–namely, with Paramecia. At first, it seems astonishing that such a “primitive” creature would have a sexual aspect to its existence.–Let me digress for a moment to remind you of something. I have already said that we human beings are obsessed with sex, but we are also obsessed with immortality and frequently fuse these ideas by conceiving of our offspring as one possible aspect of eternal survival. In a fascinating and intricate way, Paramecia have actually managed to pull off this remarkable feat–sort of. In the last half of the 19 ^th and the first half of the 20^th Centuries, there was a good deal of speculation about creatures such as Paramecia and Amoebae being immortal but, in a rather odd sense, because they have to keep dividing. Suppose we have a Paramecium labeled “X” and further suppose that it divides into X1 and X2 and here, although they are perversely dividing to multiply, they are messing up another aspect of arithmetic as well, since now X1+X2 does not equal X. What we encounter here is the bizarre circumstance of the parent transforming into two children which though similar in many respects to the parent, are not identical to the parent and possibly not even to each other. Identity is a very complex and tricky concept. Consider further, that within a matter of days X1 may become X1a and X1b and that X2 may become X2a and X2b. For at least a century, microbiologists have used monocultures; that is, cultures in which all of the organisms derive from the division of an initial single organism. One of the prime reasons for doing this was to produce strains of an organism that were genetically “identical”–another myth for another essay. But, granted, monocultures could create hundreds, even thousands, of Paramecia which are virtually “identical”–that is, with no difference which we can analytically determine. However, from research of another aspect of Paramecia, we do know that such indiscernible differences exist, but more about this in a minute.

Most modern Westerners tend to think of immortality in terms of personal survival of one’s individual ego, so a conception of immortality in which “you” survive in terms of multiple near-identical copies strikes us as quite odd. In fact, the application of this conception to the human situation becomes distinctly bizarre.

Consider the following case. Imagine an incredibly sophisticated machine which can scan your structure down to the atomic level and store in a giant computer every bit of information about you, including not only your biochemical and biophysical constitution, but your memories and experiences as well. Once this is done, you are incinerated. The computer has been programmed, however, to reconstitute you in 50 years ( a new wrinkle on time travel). So, after 50 years, the robots which the computer controls, fashion lumps of clay into a human form and then the computer feeds in all the stored data, so that you, rather like a high-tech Golem, live once again. Or do you? Is it really you? or merely a simulacrum of the highest order. Again, Westerners tend to believe in a kind of “soul-principle” which constitutes individuality. So now, the question arises of whether or not that essence could be preserved in a computer and then reconstituted. Truly a mind-boggling problem, but let’s make it even more interesting in the manner of the protozoa. Suppose that everything goes perfectly and the computer does the reconstitution exactly as instructed, but with one tiny, little glitch–it creates 2 of you! You can easily imagine the sort of argument that would ensue:

“ I’m the real Ralph!”

“ No, I’m the real Ralph!”

and on and on, until finally, they probably try to kill each other. But let’s suppose they don’t; let’s imagine rather that Ralph1 stalks off to the seashore convinced that he’s the one and only genuine Ralph and that Ralph2 heads for the mountains with precisely the same conviction about his uniqueness and authenticity. Clearly each is going to have some new experiences and acquire new memories that the other Ralph won’t have, so after a short time, we would be able to distinguish Ralph1 from Ralph2 by the difference in the accounts of their recent experiences–but not so with Paramecia; for them we will have to find a different way. But we’re not quite through with the Ralphs yet. Let us suppose that the computer error has a second phase such that after 10 days each Ralph would replicate again, so that after 10 days there would be 4 Ralphs; after 20, 8 Ralphs and so on. Soon the Ralphs would have great and greater differences from the original Ralph. This is probably true with Paramecia too, but right now we don’t have the means for detecting such differences, except one significant one and that, only indirectly, and, I promise, I’ll get to it in just a moment.

It has long been known that Paramecia, as well as a lot of other ciliates, engage in a form of sex called conjugation and, as you can see from the image, two Paramecia fuse together and while continuing to swim exchange genetic material and that, of course, is what sex is all about (well, mostly).
 

Conjugation triggers a series of complex actions; not only is there a fusion of a portion of the membranes and the exchange of genetic material, but the chromosomes divide and repairs are made to genes–an altogether remarkable process. After a time, the two organisms separate and go off to smoke a cigarette (I know, I know, not politically correct, but it’s better that the tobacco companies sell cigarettes to Paramecia than humans). After conjugation, things get really interesting, bizarre, and amazingly complicated. What is mind-boggling is that the two Paramecia just took a step toward immortality! If they hadn’t mated, then their days were numbered, since it has been discovered that, at least in certain strains, there is a limit to the number of times that the organisms can divide, which is somewhere around 200. Without, at this point, getting into the issue of strains, clones, variety, subspecies, and species, I will just talk about Paramecia, although a large part of the research has focused on P. aurelia .

In human terms, a translation of the Paramecium situation would be roughly that if you have sex, you get to go on living (that is, dividing), but if you don’t, then after a certain number of divisions, you age and die. All of this, of course, with the proviso that you don’t get collected by some amateur microscopist and get subjected to sadistic experiments. So, the next question is: What could account for this extraordinary set of events? One thing we can be certain of is that the explanation isn’t simple nor is it fully known. Experiments addressing this “immortality” issue have been conducted since the latter part of the 19^th Century and now recent high technologies have been brought to bear on these problems. Studies on cellular aging have become increasingly important in the last two decades and have led, among other things, to the postulation of a genetic “switch” and not only in cells, but in entire organisms, such as Paramecium. Whatever the mechanism, it is clear that when all goes well, there are 3 key changes which take place: rejuvenation, genetic repair, and the expulsion of accumulated metabolic toxins.

When conjugation is initiated, the micronuclei in each organism divide and produce extras which are eventually discarded and only one, which has been repaired, remains and then an exchange takes place between the mates. The process is surprisingly complex, because not just any mate will do; the two have to be of different “mating types” in order to set the genetic “switch”. How all of this works is not precisely known, since no distinctive morphological differences have thus far been discerned. What is known is that if such mating does not occur the strain begins to weaken and then dies off. So far no one has invented any Piagra. So, in the case of Paramecia, having sex with the right mating type can extend life.

Well, not always. Even in the microworld, one has to watch out for the punks. There is a strain of Paramecia designated the Kappa strain. It contains minute Kappa particles and in the process of conjugation, some of these particles are passed to its non-Kappa mate. The Kappa strain can be distinguished, because they wear little T-shirts that say: “Kappas are Kinkier!” Actually, of course, it’s because the Kappa particles are detectable, but this strain is indeed kinkier, because the particles kill the non-Kappa strains! So, even at the level of micro-organisms, sex can kill. What are these strange Kappa particles? Conjectures have included toxins, aberrant bits of genetic material, viroids, and prions. At the moment, the view that seems to have the most support is that they are viroids.

Some ciliates have developed an additional strategy to extend their lives–autogamy. This remarkable process is one which I first came upon when I was studying Lacrymaria olor. I’ll give a very brief sketch here. If you want a slightly more detailed discussion, you can find it in my article on Lacrymaria.

There seems to be some disagreement about whether Lacrymaria has one or two macronuclei. I stained some specimens with Acridine Orange and examined them with epi-fluorescence. This stain is rapidly taken up by genetic material and fluoresces very brightly which, I thought, should give me a clear idea of the number of macronuclei. In one specimen, I found 5, in another 3, in yet another 7, and in another 4! As W.C. Fields would say: “Godfrey Daniel!” What was going on? My first thought was that I had made some kind of error in preparing the specimens, so I did it again and then again, and I was still finding 3,6,2,4, or 5 macronuclei. Clearly this required some investigation of the relevant literature and that’s when I learned about autogamy. Some ciliates, when environmental conditions are poor and/or another mating type is not available, initiate autogamy; a process in which the macronucleus is divided up into a number of pieces; then, incredibly, genetic repair is undertaken, the macronucleus (or maybe the 2 macronuclei) recombine and–voilá -a new, improved version. This extraordinary feat then allows the Lacrymaria to go on dividing until it can find the right mate at a protozoan singles’ bar.

Before we venture beyond the kingdom of the protist, I want to say a word or two about one of the sexual superstars of the microworld–Volvox. If you’re not familiar with this beauty, then go look at Wim van Egmond’s images–far better than anything I could produce. Volvox is a colony of tiny flagellates varying from hundreds to thousands of cells depending on the species. How they coordinate movement is a wonderful puzzle for some clever person to solve. But, at the moment, we’re more interested in the salacious stuff–sex. Volvox has the brilliant strategy of creating “daughter” colonies within itself while it’s still active and thriving. Even more amazing is the fact that sometimes all of the “daughter” colonies will be female, while in other specimens all the “daughter” colonies will be male, and in yet others, there will be a mixture of male and female “daughter” colonies. A first-rate outrage for any right-thinking Puritan!

We humans don’t like ambiguity and so we establish lots of rules to define the social roles which people are expected to accept. However, as we are learning more and more, human sexuality is psychologically, physiologically, and anatomically ambiguous. The classic and rather rare case is the hermaphrodite who posseses both male and female genitalia. However, a very difficult and much more frequent anomaly is the case of ambiguous anatomical genitalia which occurs in about 1 birth in every 4,000. These days surgeons generally urge parents to allow a surgical procedure that anatomically defines the child as a female, in large part, because that surgery is simpler than that required to anatomically define the child as a male.

In spite of our attempts to eliminate ambiguities, nature thrives on them and is remarkably inventive at producing cases that are potentially disconcerting to us. Imagine if human beings could have a couple dozen children at once and that the mother transferred them to the male’s body for fertilization, gestation and birth! Such is the case with the seahorse. I suspect that if it worked that way for us, we would have a radically different system of social order.

Nature also provides models for the ultrafeminist. In some rotifers and cladocerans reproduction is exclusively parthenogenic, producing only females and in some of those species, no males have ever been discovered. Or for those feminists who like to have males around upon whom to exercise female dominance, the deep sea proves some striking examples.

There is an abyssal anglerfish where the male is very tiny in relationship to the female. The male attaches himself in the area of the genital pore of the female and then her skin gradually grows around him. She provides him nourishment and protection and he provides her with sperm to fertilize her eggs–a class sex slave. Interestingly, he becomes a kind of parasite and yet an essential factor in the perpetuation of the species.

Some organisms, among them bryozoans and certain ascidian tunicates, employ not only sexual reproduction, but “budding” as well. They extend a “tube” or stolon which then develops into a new zooid. This process can continue until the colony covers a considerable area. Many of you, when walking along the beach, have noticed white encrusting mats on pieces of kelp. These are bryozoan colonies. Scuba divers may encounter gelatinous masses attached to rocks or pilings, some of them measuring over a foot in diameter. These are “sea pork”, a kind of colonial tunicate, consisting of hundreds, sometimes, thousands of individuals.

Human beings argue with great vehemence about the issue of sexual identity and whether or not that identity is determined by nature or is a matter of choice. The consequence of this debate can have enormous impact for many individuals, but the consequence for the species are insignificant. A number of scientists have estimated that the optimal population for planet Earth is about 1 billion people. In spite of starvation, diseases, disasters and wars the population is now approaching 6.5 billion! Estimates for the year 2050 are 10 billion!! So, the long and the short of it is, that even if there are a few million people, who as a consequence of differences in sexual identity, chose not to reproduce–have no fear, Earth is not going to run short of people, short of a colossal stupidity such as thermonuclear war.

The reason I bring this up is that there are some fascinating reef fish which I call the “Christine Jorgensen” fish. These fish–and there are hundreds of different species–can change sex! And they do so in a matter of hours and with no great demand on their metabolic system. Most can make only a monodirectional change, that is a male can change into a female or a female can change into a male, but in only a few species, can there be a bidirectional change where a male can turn into a female and then back into a male. How’s that for rampant perversity?! Nature doesn’t have any respect for our rules. Shame on you, Mother Nature! All of this raises the intriguing, highly disputed, and difficult issue of “natural law”, for which theologians have caused the killing of many trees in order to write about this subject at an inordinate length. Can nature–in particular, animals be immoral? Theologians don’t seem to worry about the morality of plants, which can also change sex, and have developed some marvelously bizarre strategies for reproduction. Another question I’ve never seen discussed is whether or not Paramecia can be guilty of sin. This may sound silly (and indeed it is), but remember that in medieval times, long and “serious” arguments took place regarding how many angels could dance on the head of a pin.

Well, once again I’ve rambled on and this has gotten rather long. So we’ll have to save the hermaphroditic snails and some other first-rate abominations for Part II.

All comments to the author Richard Howey are welcomed.

Editor's note: Visit Richard Howey's new website at http://rhowey.googlepages.com/home where he plans to share aspects of his wide interests.

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