The Seven Mysteries of Life

by Guy Murchie

  Still another example of an animal-like vegetable, this time rather sinister in its form and behavior, is the deadly dodder, a parasite upon other plants, which advances toward its host-prey with a kind of malicious deliberation like a very slow snake with fangs in its "stomach" instead of its "head." When the dodder sprouts from the ground, its tendril-like stem seems to sniff and listen for a few hours, then, somehow sensing the presence of its victim (probably through the light-sensitive cells in its leaves which direct it to relative shade), it turns its tip and grows rapidly toward it - and often, by the end of the second day, has coiled itself firmly around and started sinking its rootlike fangs (called haustoria) straight through the cambium layer into the sap channels. Then, having "tasted blood" so to speak, it pulls its roots completely out of the ground and becomes a full-fledged parasite, as shown in the illustration, well able to advance like a serpent toward any prey that appeals to it. One further snaky feature of the dodder is that it is bare of twigs or leaves, having abandoned them millions of years ago when it evolved, in their place, scales!

  Although plants in general, being relatively conservative in evolution, move and respond much more slowly than do most of the complex animals, the plants' behavior as seen in a time-lapse movie becomes surprisingly animal-like. I saw a month's growth of a climbing vine thus shortened into a minute in which the vine's tip would rise upward under the stimulus of light and warmth each morning (one second long), then relax and settle back as the sun went down each evening (another second). But with the coming of every new day the vine reached upward with a fresh effort and always in a slightly different direction, usually a little higher than the day before. With the time dimension thus speeded up by a factor of 40,000, it was obvious that the plant was not only eager to climb but also, through the combination of progressively augmenting its strength and varying its aim from day to day apparently in a random manner, along with its presumed hormone guidance from light and gravity, it was groping upward with a kind of vegetal purpose, methodically and rhythmically reaching to and fro, up and up, mostly in empty air, but nevertheless rising higher and higher and still higher with a deliberate attitude of expectancy - even of confidence. And every now and then the vine's groping tendril or finger would touch and discover a new support somewhere above it, whereupon, with a seeming sigh of gratitude, it would feel and fathom its way around this handhold, embrace it like a trusted friend, then continue upward with renewed faith. Could this be, I thought, the way animality arose out of vegetality - out of the patient and constant struggles of vegetation to achieve a position, a condition, a station in life almost but not quite beyond reach? Could this be what Bose meant when he wrote, "There is no life-reaction in even the highest animal which has not been foreshadowed in the life of the plant?" Could this be what God was saying when He told Isaiah (40:6) that "all flesh is grass, and all the goodliness thereof is as the flower of the field ..."?

  DOMESTICATION

  Right here might be a good place to raise the fundamental question as to whether there can possibly ever be two objects or factors in the universe that are not in some sense related. It is not a new question, for the fact of universal relatedness - assuming it is a fact - has been curiously anticipated by philosophers for millenniums. Anaximander of Miletos in ancient Greece, for one, is said to have taught that "the primary substance of the world is infinite, eternal and all encompassing." Two thousand years later Bruno went further in writing that "all reality is one in substance, one in cause, one in origin ... and every particle of reality is composed inseparably of the physical and the psychic. The object of philosophy, therefore, is to preserve unity in diversity, mind in matter and matter in mind ... to rise to that highest knowledge of the universal unity which is the intellectual equivalent of the love of God."

  Expectably Bruno got burned at the stake for this and other heresies, but his thought lives on and has been reinforced both by modern science and modern religion, a reinforcement probably most specifically evident in the remarkable recent growth of the Baha'i Faith, of which we will hear more in Chapter 23. No educated person should be surprised, therefore, that Earth's minerals, vegetables and animals have been found to converse and interrelate in almost every conceivable way. And one of the most significant and fascinating forms of interspecific, and often interkingdom, relation is the phenomenon called domestication, which also increasingly affects all life. I used to think that man many eons ago must have deliberately set out to tame the dog, the goat, the cat, etc., and that his eventual domination of the animal signaled victory in a one-sided campaign of pursuit, capture and control. But the evidence strongly suggests that domestication was largely unplanned and in most cases either accidental or entered into as willingly by the animal as by man.

  The dog seems to have been the earliest creature to join man in close partnership, perhaps very tentatively hundreds of thousands of years ago, but pretty finally somewhen around 20,000 years ago. And this presumably happened as much because the dog was attracted by scraps and bones left around the campsite as by man's appreciation in return of barked announcements whenever a stranger approached. Indeed it likely took form as a true symbiosis or working partnership for mutual benefit - a deal in which four-footed sentinels freely served for their keep on a day-to-day basis with no contract and no questions asked. Only much later, probably without realizing it, did man gradually enslave the dog by controlling his food and his breeding, little by little turning a partner into a parasite.

  And perhaps it was only a short while after the dog joined man that the reindeer, a salt-loving ruminant, like Wise made a compact of sorts with him, in effect offering his freedom for the chance to lick up any salty substance such as human urine. But this time it was man who accepted the major role of parasite, as he took to following the migrating herds of the large beasts like a flea following a dog. This happened in many northern countries from Lapland to Siberia and, from all accounts, it persisted intermittently for millenniums before man learned to corral the reindeer, to breed them, decoy them in hunting, milk them, ride them and eventually harness them to pack loads and haul sledges.

  Again, in the case of goats, sheep, cattle and probably asses of the Nile valley, these animals gravitated toward easier grazing conditions near human habitations beginning some 8000 years ago and most certainly where and when agriculture had started to produce tempting orchards, gardens and fields of grain. So eventually fencing in the creatures along with their fodder was, in a sense, only a formalizing of an already-established relationship.

  In similar ways such scavengers as the pig and the duck entered man's domain as willing servants with a natural capacity to convert stale vegetable scraps into fresh whole meat. Then came the buffalo, the elephant, the rabbit and the goose, all opportunistically raiding man's crops, gaining confidence with each success, in due time bringing along mothers with their young which could readily be captured and raised as tame dependents.

  A few creatures also ventured tardily into the human dominion as eager, often welcome, pest-destroyers, among them the ferret, the mongoose and, most notably, the cat which, although held sacred in Egypt, was eventually shipped from there in significant numbers to Sybaris and lesser European ports during the last millennium B.C. Still other kinds of animals may have been purposefully tamed by people already familiar with domestication, like the inhabitants of the Indus valley who captured and bred the shy jungle fowl in the third millennium B.C., probably initially for cock fighting but soon for egg production. There were also the Egyptians who long experimented with captive gazelles, ibex, oryx, addax and other antelopes, with monkeys, cheetahs and even hyenas (as early as 3000 B.C.) which they force-fed for the table - this being part of the unending succession of animals enslaved all over the world: the horse of Turkestan broken to chariots in the third millennium, the camel of Arabia and the Near East saddled for caravans about the same time.

  Birds subjugated before the Christian era included the falcon in much of A
sia and eastern Europe, the peacock from India and Burma, the pheasant in Persia and the Caucasus, the dove and quail of the Near East, the pelican and crane in Egypt and the ostrich and guinea fowl from several parts of Africa. Silk moths likewise had been made domestic by the Chinese, reputedly about 3000 B.C., and the honey bee possibly as early as 5000 B.C. in Egypt, whence beekeeping spread to Asia and Europe. And there were four kinds of domesticated fish bred by man in antiquity: the Roman eel, which was not only fattened for eating but often kept as a pet and on occasion dressed up with jewels, including earrings; the carp in both ancient China and later Europe; then the goldfish under the medieval Sung Dynasty, followed by the colorful little paradise fish in modern China.

  In America about the only domesticated animals in sight when the Spaniards arrived were the turkey, guinea pig, llama, alpaca and a few kinds of dog, even including (among the Incas) a bulldog and a dachshund. The load-carrying llama and wool-bearing alpaca are of course the domestic cousins of the wild guanaco and vicufla, these four interbreeding Andean animals being closely related to the camels of Asia and Africa, which, like the early horses, are known to have migrated westward from America while there was still a land-bridge in the present region of the Bering Sea.

  But although the so-called Indians of America evidently domesticated few animals and had no tame goats, sheep, bison or even caribou, surprisingly, they were ahead of the Europeans in the number of vegetables they had domesticated, which included potatoes (white and sweet), corn, squash, pumpkin, lima beans, manioc, coca, chocolate, vanilla, chili, chive, amaranth, sunflower, quinine, tobacco, sarsaparilla, peyote, such fruits as tomato, avocado, pineapple, papaya and guava, and scores of berries, herbs and drugs. Domestication in the vegetable kingdom, however, may have been no more of a one-way conquest than it was in the animal kingdom, for lowly weeds have shown that they are just as able to choose civilizations as are dogs or swans. In fact this vegetal capability is about all we need to explain how the barley plant, rejected by the earliest human farmers as a "weed" in wheat, nevertheless managed in time to become a valued "grain" through its patient persistence in "adopting" man as the likeliest provider of enough space to grow in. Something similar happened in the case of corn in America, which the Indians domesticated but which in turn domesticated them as their economy, settlement pattern and even social organization followed the life cycle of this indispensable plant and its many races which now exceed 300.

  The roster of domestication of course increases by several species yearly and it already amounts to hundreds, including the names of new animals being added at an accelerating rate as every creature from crickets (in China and Japan) to the remora (a fish trained to catch sea turtles by suction in tropical seas) to musk oxen (in Vermont) is drawn into man's fold. And the many kinds of experimental animals in research laboratories seem to be almost erupting into what could be called their own special new subkingdom of regimented, computerized members, already totaling hundreds of millions of mice, rats, hamsters, guinea pigs, rabbits, dogs, cats, monkeys, pigeons, fruit flies, flatworms, etc., some of them being species tailor-made for research, like a synthetic breed of fast-growing miniature pigs that has become the cheapest, handiest "pseudo-human physiology" yet available. Come to think of it, it is doubtful whether any large land mammals remain on Earth that are not at least nominally under the purview of some nation's game laws, if not restricted directly or indirectly by the confines of a national or smaller park. The muntjac, for instance, a small Asian deer introduced into Britain, is reported to be "spreading" along with badgers and foxes into the London suburbs, evidently feeling safer near houses. And it seems only a question of time before all the Earth's creatures, even insects, plankton and microbes, must live, breed and evolve at the dispensation of man.

  Below the human level, what might be termed domestication of one species by another usually turns out to have evolved to some stage between voluntary symbiosis and parasitism, and the phenomenon shows up all over creation. Ants, for example, millions of years ago had already domesticated more varieties of animals than had man before the twentieth century, including a score of other species of insects, whose stations range from pets to furniture. Some ants are sophisticated farmers, growing various crops from mushrooms in underground beds to rice which they sow in November, weed all winter and reap in June. They exploit their own offspring too, a variety in Ceylon having been observed making its nests in trees out of leaves sewn together with spun-silk threads extorted from the helpless larvae, who, possessed of spinning glands but no legs, are easily picked up and used as precision tools by their elders, each grub a living combination of distaff and shuttle that can be artfully squeezed while its head is applied alternately against one side then the other of the leaf parts being stitched into one. Exploitation however, even between ants, may be in danger of backfiring when it is carried to the extreme of certain specialized, slave-hunting species who know nothing but how to raid other ants' nests, from which they steal and bring back pupae to raise as cooks, butlers and serving maids, without whom they would starve since they have literally (without realizing it) let themselves become the parasites of their own slaves.

  The most primitive sort of domestication I remember having heard of is probably that in which certain aggressive viruses known as "phages" (page 160) take charge of susceptible, if not seducible, bacteria by injecting themselves directly into their bodies. And these bacteria, which are hundreds of times bigger than the phages, appear for a few minutes to have "swallowed" them but actually the phages are penetrating or ravishing, the genes of the bacteria and somehow combining their own DNA with the bacterial DNA to spawn new phages that in half an hour make each bacterium swell up and burst forth with a new viral generation.

  AND NOW ECOLOGY

  Beyond what can be called domestication of course there exists a vast and complex spectrum of symbiotic relations among the creatures of all the kingdoms, ranging from even-swap mutualism such as the tickbird-rhinoceros partnership to out-and-out parasitism like barnacles on a whale's belly. And there are uncountable variations of cause-and-effect interrelations that keep the new science of ecology almost unfathomable. Did you hear of the case of the sudden decrease in the population of wood ducks at a lake in Maine? When a local naturalist was asked to help, he soon discovered skunks eating the ducks' eggs and naturally concluded he had found the source of the decrease. But when all the skunks in the area had been eliminated, the ducks did not recover and in fact disappeared faster than ever. Two years later hardly one could be found. So a top-notch ecologist was called in and, after weeks of very careful sleuthing, he deduced that the skunks had actually been helping the ducks more than hurting them because, although the skunks occasionally ate duck eggs, their main diet in spring was the eggs of snapping turtles. So, with the skunks gone, the snapping turtle population had skyrocketed, inevitably proliferating the turtles' favorite sport of grabbing the legs of ducklings from underwater, pulling them down and eating them.

  Even the World Health Organization botched its well-intentioned effort to control malaria in Borneo by spraying native villages with poisonous DDT before its effects were fully understood. Although the malarial mosquitoes were eliminated on schedule, roaches and caterpillars in the houses merely absorbed the poison, passing it on to small lizards feeding on them, whose nerves were impaired, reducing their agility so much that not one of them escaped being caught and eaten by cats. But cats are very susceptible to DDT and they all soon died, permitting forest rats to move into the houses, carrying with them fleas infected with bubonic plague. As if that were not enough, the roofs of the houses started falling in because the thatch was being devoured by the caterpillars who were no longer being kept in check by lizards. So it shouldn't surprise anyone that no native Bornean could think of any convincing objection when a gathering of local witch doctors was seen making incantations to summon back: good old malaria!

  It has always seemed to me appropriate that tigers and
zebras are striped with grassy designs, for they not only benefit individually by this vegetal disguise but it symbolizes the two-way exchange in which grasses directly and indirectly provide food and air for the animals while the animals return the favor by helping distribute seeds and conserving the grasses by limiting the trampling and grazing of the herds. Of course all such interrelationships evolve and, along with the walrus and the whale, who relatively recently evolved back to sea, several members of the vegetable kingdom who also had learned to dwell on dry land have likewise reverted to the deep and, with man's help, some of their species such as turtle grass ("more nutritious than wheat") are now serving as fodder for sheep and cattle on land as well as for sea horses in the wet meadows below.

  A few insects, I am told, borrow and use weapons of defense from trees. One such is the sawfly larva, who feeds on Scotch pine needles and stores their toxic resin in two pouches in his foregut to squirt at ants and spiders who threaten him. And several microbes have evolved what may be the most vital predator-prey relationship ever observed by science, something convincingly demonstrated when a researching biologist took what's known as a nutrient broth and added to it some tasty paramecia and hungry didiniums (page 86). First the paramecia, feeding on the broth, experienced a population explosion lasting two days, whereupon the didiniums, preying on the paramecia, multiplied a third as fast for two more days, while the paramecia rapidly declined in numbers until they were extinct on the fifth day, all devoured by didiniums who in turn were starved out of existence by the seventh day.