Lives of a Cell Page 12

The story told by myxotricha is as deep as any myth, as profoundly allusive. This creature has lagged behind the rest of us, and is still going through the process of being assembled. Our cilia gave up any independent existence long ago, and our organelles are now truly ours, but the genomes controlling separate parts of our cells are still different genomes, lodged in separate compartments; doctrinally, we are still assemblages.

  There is another protozoan, called blepharisma, telling a long story about the chanciness and fallibility of complex life. Blepharisma is called that because of a conspicuous fringe of ciliated membranes around the oral cavity, which evidently reminded someone of eyelashes (blepharidos). The whole mythlike tale has been related in a book by Giese. Blepharisma has come much further along than myxotricha, but not far enough to be free of slip-ups. There are three different sets of self-duplicating nuclei, with the DNA in each set serving different purposes: a large macronucleus, governing the events in regeneration after injury, a set of eight or more micronuclei containing the parts of the genome needed for reproduction, and great numbers of tiny nuclei from which the cilia arise.

  One part of the organism produces a pinkish pigment, now called blepharismin, which is similar to hypericin and certain other photosensitizing plant pigments. Blepharismin causes no trouble unless the animal swims into sunlight, but then the pigment kills it outright. Under certain circumstances, the membrane surrounding blepharisma disintegrates and comes independently loose, like a cast-off shell, leaving the creature a transient albino. At times of famine, a single blepharisma will begin eating its neighbors; it then enlarges to an immense size and turns into a cannibalistic giant, straight out of any Norse fable. Evidently, this creature still has trouble getting along with the several parts of itself, and with the collective parts of other blepharismae.

  There are innumerable plant-animal combinations, mostly in the sea, where the green plant cells provide carbohydrate and oxygen for the animal and receive a share of energy in return. It is the fairest of arrangements. When the paramecium bursaria runs out of food, all he needs to do is stay in the sun and his green endosymbionts will keep him supplied as though he were a grain.

  Bacteria are the greatest of all at setting up joint enterprises, on which the lives of their hosts are totally dependent. The nitrogen-fixing rhizobia in root nodules, the mycetomes of insects, and the enzyme-producing colonies in the digestive tracts of many animals are variations of this meticulously symmetrical symbiosis.

  The meaning of these stories may be basically the same as the meaning of a medieval bestiary. There is a tendency for living things to join up, establish linkages, live inside each other, return to earlier arrangements, get along, whenever possible. This is the way of the world.

  The new phenomenon of cell fusion, a laboratory trick on which much of today’s science of molecular genetics relies for its data, is the simplest and most spectacular symbol of the tendency. In a way, it is the most unbiologic of all phenomena, violating the most fundamental myth of the last century, for it denies the importance of specificity, integrity, and separateness in living things. Any cell—man, animal, fish, fowl, or insect—given the chance and under the right conditions, brought into contact with any other cell, however foreign, will fuse with it. Cytoplasm will flow easily from one to the other, the nuclei will combine, and it will become, for a time anyway, a single cell with two complete, alien genomes, ready to dance, ready to multiply. It is a Chimera, a Griffon, a Sphinx, a Ganesha, a Peruvian god, a Ch’i-lin, an omen of good fortune, a wish for the world.

  ON VARIOUS WORDS

  The idea that colonies of social insects are somehow equivalent to vast, multicreatured organisms, possessing a collective intelligence and a gift for adaptation far superior to the sum of the individual inhabitants, had its origin in the papers of the eminent entomologist, William Morton Wheeler, who proposed the term Superorganism to describe the arrangement. From 1911 to the early 1950s this ranked as a central notion in entomology, attracting the attention of many fascinated nonentomologists. Maeterlinck and Marais wrote best-selling books on the presumed soul that must exist somewhere in the nests of ants and termites.

  Then, unaccountably, the whole idea abruptly dropped out of fashion and sight. During the past quarter-century almost no mention of it is made in the proliferation of scientific literature in entomology. It is not talked about. It is not just that the idea has been forgotten; it is as though it had become unmentionable, an embarrassment.

  It is hard to explain. The notion was not shown to be all that mistaken, nor was it in conflict with any other, more acceptable view of things. It was simply that nobody could figure out what to do with such an abstraction. There it sat, occupying important intellectual ground, at just the time when entomology was emerging as an experimental science of considerable power, capable of solving matters of intricate detail, a paradigm of the new reductionism. This huge idea—that individual organisms might be self-transcending in their relation to a dense society—was not approachable by the new techniques, nor did it suggest new experiments or methods. It just sat there, in the way, and was covered over by leaves and papers. It needed heuristic value to survive, and this was lacking.

  “Holism,” a fabricated word, has been applied to concepts like the Superorganism. One wonders whether this word may not itself have scared off some investigators; it is a word with an alarming visage. General Jan Smuts, who invented it out of whole cloth in 1926, might have done better with “Wholism”; it would have served the same etymological purpose and might have been just secular enough to survive this kind of century. As it is, there is doubt for its future. Holism is in some of the scientific glossaries but has not yet made it into most standard dictionaries of English. It got as far as the Supplement volume of the new OED, which is something, but not enough to assure survival. Perhaps it will die away, along with Superorganism.

  I cannot quarrel with any of this. If an idea cannot move on its own, pushing it doesn’t help; best to let it lie there.

  It may be, though, that the pushing was tried in the wrong direction. Colonies of ants or termites, or bees and social wasps, may in fact be Superorganisms by Wheeler’s criteria, but perhaps that is the end of that line of information as far as insects are concerned, for the time being. Maybe it would work better if you tried it out on another social species, easier to handle. Us, for one.

  It has long troubled the entomologists that the rest of us are always interfering in their affairs by offering explanations of insect behavior in human terms. They take pains to explain that ants are not, emphatically not, tiny mechanical models of human beings. I agree with this. Nothing that we know for sure about human behavior is likely to account for what ants do, and we ought to stay clear of it; this is the business of entomologists. As for the ants themselves, they are plainly not in need of lessons from us.

  However, this does not mean that we cannot take it the other way, on the off chance that some of the collective actions of ants may cast light on human problems.

  There are lots of possibilities here, but if you think about the construction of the Hill by a colony of a million ants, each one working ceaselessly and compulsively to add perfection to his region of the structure without having the faintest notion of what is being constructed elsewhere, living out his brief life in a social enterprise that extends back into what is for him the deepest antiquity (ants die at the rate of 3–4 per cent per day; in a month or so an entire generation vanishes, while the Hill can go on for sixty years or, given good years, forever), performing his work with infallible, undistracted skill in the midst of a confusion of others, all tumbling over each other to get the twigs and bits of earth aligned in precisely the right configurations for the warmth and ventilation of the eggs and larvae; but totally incapacitated by isolation, there is only one human activity that is like this, and it is language.

  We have been working at it for what seems an eternity, generation after
articulate generation, and still we have no notion how it is done, nor what it will be like when finished, if it is ever to be finished. It is the most compulsively collective, genetically programmed, species-specific, and autonomic of all the things we do, and we are infallible at it. It comes naturally. We have DNA for grammar, neurons for syntax. We can never let up; we scramble our way through one civilization after another, metamorphosing, sprouting tools and cities everywhere, and all the time new words keep tumbling out.

  The words themselves are marvels, each one perfectly designed for its use. The older, more powerful ones are membranous, packed with layers of different meaning, like one-word poems. “Articulated,” for instance, first indicated a division into small joints, then, effortlessly, signified the speaking of sentences. Some words are gradually altered while we have them in everyday use, without our being aware until the change has been completed: the ly in today’s adverbs, such as ably and benignly, began to appear in place of “like” just a few centuries ago, and “like” has since worn away to a mere suffix. By a similar process, “love-did” changed itself into “loved.”

  None of the words are ever made up by anyone we know; they simply turn up in the language when they are needed. Sometimes a familiar word will suddenly be grabbed up and transformed to mean something quite strange: “strange” is itself such a word today, needed by nuclear physicists to symbolize the behavior of particles which decay with peculiar slowness; the technical term for such particles now is “strange particles,” and they possess a “strangeness number(S).” The shock of sudden unfamiliarity with an old, familiar word is something we take in stride; it has been going on for thousands of years.

  A few words are made up by solitary men in front of our eyes, like Holism out of Smuts, or Quark out of Joyce, but most of these are exotic and transient; it takes a great deal of use before a word can become a word.

  Most new words are made up from other, earlier words; language-making is a conservative process, wasting little. When new words unfold out of old ones, the original meaning usually hangs around like an unrecognizable scent, a sort of secret.

  “Holism” suggests something biologically transcendental because of “holy,” although it was intended more simply to mean a complete assemblage of living units. Originally, it came from the Indo-European root word kailo, which meant whole, also intact and uninjured. During passage through several thousand years it transformed into hail, hale, health, hallow, holy, whole, and heal, and all of these still move together through our minds.

  “Heuristic” is a more specialized, single-purpose word, derived from Indo-European wer, meaning to find, then taken up in Greek as heuriskein, from which Archimedes was provided with Heureka!

  There are two immense words from Indo-European, gene and bheu, each a virtual anthill in itself, from which we have constructed the notion of Everything. At the beginning, or as far back as they are traceable, they meant something like being. Gene signified beginning, giving birth, while bheu indicated existence and growth. Gene turned itself successively into kundjaz (Germanic) and gecynd (Old English), meaning kin or kind. Kind was at first a family connection, later an elevated social rank, and finally came to rest meaning kindly or gentle. Meanwhile, a branch of gene became the Latin gens, then gentle itself; it also emerged as genus, genius, genital, and generous; then, still holding on to its inner significance, it became “nature” (out of gnasci).

  While gene was evolving into “nature” and “kind,” bheu was moving through similar transformations. One branch became bowan in Germanic and bua in Old Norse, meaning to live and dwell, and then the English word build. It moved into Greek, as phuein, meaning to bring forth and make grow; then as phusis, which was another word for nature. Phusis became the source of physic, which at first meant natural science and later was the word for medicine. Still later, physic became physics.

  Both words, at today’s stage of their evolution, can be taken together to mean, literally, everything in the universe. You do not come by words like this easily; they cannot just be made up from scratch. They need long lives before they can signify. “Everything,” C.S. Lewis observed in a discussion of the words, “is a subject on which there is not much to be said.” The words themselves must show the internal marks of long use; they must contain their own inner conversation.

  These days it is reassuring to know that nature and physics, in their present meanings, have been interconnected in our minds, by a sort of hunch, for all these years. The other words clinging to them are a puzzlement, but nice to see. If you let your mind relax, all the words will flow into each other in an amiable sort of nonsense. “Kind” means a relation, but it also means “nature.” The word for kind is the same as the word for gentle. Even “physics,” save us, is a kind of “nature,” by its nature, and is, simultaneously, another kind of kind. There are ancient ideas reverberating through this structure, very old hunches.

  It is part of the magic of language that some people can get to the same place by the use of totally different words. Julian of Norwich, a fourteenth-century hermitess, said it so well that a paragraph of hers was used recently by a physicist for his introduction to a hard-science review of contemporary cosmological physics: “He showed me a little thing, the quantity of an hazelnut, in the palm of my hand, and it was as round as a ball. I looked thereupon with the eye of my understanding and thought: What may this be? And it was answered generally thus: it is all that is made.”

  LIVING LANGUAGE

  “Stigmergy” is a new word, invented recently by Grassé to explain the nest-building behavior of termites, perhaps generalizable to other complex activities of social animals. The word is made of Greek roots meaning “to incite to work,” and Grassé’s intention was to indicate that it is the product of work itself that provides both the stimulus and instructions for further work. He arrived at this after long observation of the construction of termite nests, which excepting perhaps a man-made city are the most formidable edifices in nature. When you consider the size of an individual termite, photographed standing alongside his nest, he ranks with the New Yorker and shows a better sense of organization than a resident of Los Angeles. Some of the mound nests of Macrotermes bellicosus in Africa measure twelve feet high and a hundred feet across, they contain several millions of termites, and around them are clustered other small and younger mounds, like suburbs.

  The interior of the nests are like a three-dimensional maze, intricate arrangements of spiraling galleries, corridors, and arched vaults, ventilated and air-conditioned. There are great caverns for the gardens of fungi on which the termites depend for their nourishment, perhaps also as a source of heat. There is a rounded vaulted chamber for the queen, called the royal cell. The fundamental structural unit, on which the whole design is based, is the arch.

  Grassé needed his word in order to account for the ability of such tiny, blind, and relatively brainless animals to erect structures of such vast size and internal complexity. Does each termite possess a fragment of blueprint, or is the whole design, arch by arch, encoded in his DNA? Or does the whole colony have, by virtue of the interconnections of so many small brains, the collective intellectual power of a huge contractor?

  Grassé placed a handful of termites in a dish filled with soil and fecal pellets (these are made of lignin, a sort of micro-lumber) and watched what they did. They did not, in the first place, behave at all like contractors. Nobody stood around in place and gave orders or collected fees; they all simply ran around, picking up pellets at random and dropping them again. Then, by chance, two or three pellets happened to light on top of each other, and this transformed the behavior of everyone. Now they displayed the greatest interest and directed their attention obsessively to the primitive column, adding new pellets and fragments of earth. After reaching a certain height, the construction stopped unless another column was being formed nearby; in this case the structure changed from a column to an arch, bending off in a
smooth curve, the arch was joined, and the termites then set off to build another.

  Building a language may be something like this. One can imagine primitive proto-Indo-European men finding themselves clustered together, making random sounds, surrounded, say, by bees, and one of them suddenly saying “bhei,” and then the rest of them picking it up and repeating “bhei” and thus beginning that part of language, but this is a restricted, too mechanistic view of things. It makes pellets out of phonemes, implies that the deep structures of grammar are made of something like cement. I do not care for this.

  More likely, language is simply alive, like an organism. We tell each other this, in fact, when we speak of living languages, and I think we mean something more than an abstract metaphor. We mean alive. Words are the cells of language, moving the great body, on legs.

  Language grows and evolves, leaving fossils behind. The individual words are like different species of animals. Mutations occur. Words fuse, and then mate. Hybrid words and wild varieties of compound words are the progeny. Some mixed words are dominated by one parent while the other is recessive. The way a word is used this year is its phenotype, but it has a deeply seated, immutable meaning, often hidden, which is the genotype.

  The language of genetics might be used in some such way to describe the genetics of language, if we knew more about both.

  The separate languages of the Indo-European family were at one time, perhaps five thousand years ago, maybe much longer, a single language. The separation of the speakers by migrations had effects on language comparable to the speciation observed by Darwin on various islands of Galapagos. Languages became different species, retaining enough resemblance to an original ancestor so that the family resemblance can still be seen. Variation has been maintained by occasional contact between different islands of speakers, and perhaps also by random mutations.