Why Cooperation Is Vital

“No organism is an island​—each one has a relationship to other organisms, directly or indirectly.”​—“Symbiosis—​An Introduction to Biological Associations.”

THE “web of life”​—how fitting that expression is, for life truly is a network of interconnected and interdependent organisms! Humans are very much a part of that web. For evidence, you need not look any further than your own body. Quietly at work in your digestive tract, an army of friendly bacteria help you to stay healthy by destroying harmful invaders and by aiding in digestion and in the production of essential vitamins. In return, you, the host, provide the bacteria with food and a supportive environment.

Similar alliances occur in the animal kingdom, especially with ruminants​—animals that chew the cud—​such as cattle, deer, and sheep. Their rumen, the first part of their multichambered stomach, hosts a veritable ecosystem of bacteria, funguses, and protozoa. By means of fermentation, these microbes break down cellulose, a fibrous carbohydrate found in vegetation, into various nutrients. Even certain insects that eat cellulose, including members of the beetle, roach, silverfish, termite, and wasp families, employ bacteria in the digestive process.

Such close cooperation among dissimilar organisms is called symbiosis, which means “living together.” * “Such alliances are fundamental to the development of every living system,” says Tom Wakeford in his book Liaisons of Life. Consider soil for a moment, for that is where many of earth’s living systems originate.

 Soil​—Practically a Living Organism!

The Bible states that soil has power. (Genesis 4:12) This is a sound statement, for healthy soil is much more than lifeless dirt. It is a complex medium for growth, bursting with organisms. Just two pounds [1 kg] may contain well over 500 billion bacteria, one billion funguses, and up to 500 million multicellular creatures, from insects to worms. Many of these organisms work together, breaking down organic matter​—such as leaf litter and animal waste—​while extracting nitrogen, which they convert into forms that plants can absorb. They also change the carbon into carbon dioxide and other compounds that plants need for photosynthesis.

Legumes, such as alfalfa, clover, peas, and soybeans, have a special affinity with bacteria, in that they allow them to “infect” their root systems. But instead of harming the plants, the bacteria stimulate the roots to grow tiny nodules. There the bacteria set up house and grow up to 40 times larger, becoming bacteroids. Their job is to “fix” nitrogen into compounds that legumes can use. In return, the bacteria receive food from the plants.

Funguses, or molds, also play a key role in plant growth. In fact, virtually every tree, shrub, and grass has a secret, underground liaison with funguses. These organisms also “infect” roots, where they help plants to absorb water and important minerals, such as iron, phosphorus, potassium, and zinc. In exchange, the funguses, which cannot produce their own food because they lack chlorophyll, absorb carbohydrates from the plant.

A plant that is highly dependent on funguses is the orchid. In the wild the alliance begins with the orchid’s dustlike seeds, which need help to germinate. Funguses also help the mature plant by compensating for its rather puny root system. Fungus, says Wakeford, “forms a large and dynamic foraging web that ensures the orchid’s nutritional needs are fully met. In turn, [the fungus] may receive small amounts of vitamins and nitrogen compounds from the plant. The orchid’s generosity has well-defined limits, however. The plant keeps the fungus in check with natural fungicides, should it show signs of attempting to stray upward from its normal home inside the roots, to colonize the orchid’s stem.”

With flowering plants, liaisons within the soil are only part of the story; they also make other, more visible alliances.

Partnerships for Propagation

When a bee alights on a flower, it enters into a symbiotic partnership with its host. The bee receives nectar and pollen while the flower gets a dusting of pollen from other blossoms of the same kind. This alliance enables flowering plants to reproduce. After being pollinated, flowers cease producing food. How do insects know that the “diner” is now closed? Flowers “tell” them in various ways. They might lose their scent, drop their petals, or change their orientation or color​—perhaps becoming duller. This may disappoint us, but it is an act of great “courtesy” to hardworking bees, who can now focus their efforts on plants that are still open for business.

In recent years the numbers of pollinators, especially bees, have been in steep decline in some areas. This is an ominous trend, for nearly 70 percent of flowering plants rely on insect pollinators. Furthermore, 30 percent of our food comes from bee-pollinated crops.

 Ants in the Garden

Certain ants also enjoy a symbiotic alliance with plants. In exchange for nest sites and food, these insects might pollinate their host, disperse its seeds, help provide its nutrients, or protect it against herbivores, whether other insects or mammals. A species of ant that sets up house in the hollow thorns of the acacia tree even destroys threatening vines, which it discovers when patrolling the territory around the tree. The acacia says thank you for this first-rate gardening service by giving the ants servings of sweet nectar.

On the other hand, some ants prefer “animal husbandry,” their charges being aphids that secrete sweet honeydew when gently stroked by the ants’ antennas. Regarding aphids, the book Symbiosis states: “The ants tend these insects like cattle, milking them for food and protecting them from predators.” Just as a dairy farmer might put his cows in the barn overnight, ants often carry aphids to the safety of the ants’ nest in the evening and return them to the “pasture” in the morning, usually to younger, more nourishing leaves. And we are not talking about just a few aphids. Ants may have  “herds” that number in the thousands in a single nest!

While still in the caterpillar stage, some species of butterflies are also tended by ants. The large blue butterfly, for example, has a symbiotic relationship with red ants. In fact, it cannot complete its life cycle without their help. As a caterpillar, it rewards its hosts with sugary excretions. Later, when the butterfly emerges from its chrysalis, it leaves the ants’ nest safe and unharmed.

Living Dangerously

If you were a bird, would you bring a live snake into your nest? “Never!” you say. Yet, one species of bird does just that​—the screech owl. The snake is called the blind snake. Instead of harming the nestlings, the snake eats ants, flies, and other insects and their larvae or pupae. According to a report in New Scientist magazine, chicks raised with a blind snake in the family “grow faster and are much more likely to survive” than those raised without the company of this living vacuum cleaner.

A bird called the water thick-knee, or water dikkop, does not team up with a mere snake; it likes to build its nest near that of a Nile crocodile​—a reptile that preys on certain birds! However, instead of becoming a meal, the water thick-knee serves as a sentry. Should danger approach either its nest or that of the crocodile, the bird will emit warning cries. If the crocodile is away, these cries will bring the reptile charging home.

Pecked and Sucked Clean

Have you ever seen birds such as cattle egrets or oxpeckers perched on the backs of antelope, cows, giraffes, or oxen, pecking at their skin? Instead of being a nuisance, the birds are actually doing their hosts a big favor  by eating lice, ticks, and other parasites that the animals cannot remove on their own. They also eat infected tissue and maggots. Oxpeckers even hiss, alerting their hosts of possible danger.

Because of its aquatic habits, the hippopotamus gets cleaned by both feathered and finned “friends.” When a hippo is in the water, fish called black labeos, a species of carp, “vacuum” away algas, dead skin, and parasites​—practically anything clinging to the animal. They even clean its teeth and gums! Other species of fish also help out​—some by cleaning wounds and others by using their long snouts to probe and nibble between the hippo’s toes and in other awkward spots.

Of course, fish also attract, and thus need to be rid of, unwanted hangers-on, such as crustaceans and external bacteria, funguses, and lice, as well as damaged or diseased tissue. To that end, marine fish usually head for their local cleaning station. There, brightly colored gobies, wrasses, and cleaner shrimps give their clients a good working over, getting a meal for their efforts. Large fish may even have an entire team of cleaners servicing them!

Client fish have various ways of signaling their desire to be cleaned. For example, some adopt unusual poses​—head down, tail up. Or they might hold their mouth and gills wide open, as if to say: “Come in. I won’t bite.” The cleaners readily oblige, even if the client is a fearsome predator, such as a moray eel or a shark. While being cleaned, some clients change color, perhaps to make parasites more visible. In aquariums without cleaner fish, sea fish “soon become infested by parasites and grow sickly,” says the book Animal Partnerships. “But as soon as a cleaner fish is put into the aquarium it sets to work to clean them up, and as if they know what is happening the others queue up to be cleaned.”

The more we learn, the more we stand in awe of the harmony and interdependence manifest in the living world around us. Like musicians in an orchestra, every organism plays its part, making the symphony of life​—including human life—​both possible and enjoyable. Surely, this is testimony to intelligent design and to a Supreme Designer!​—Genesis 1:31; Revelation 4:11.

The Only Source of Disharmony

It is truly sad that humans often manifest a lack of cooperation with the natural world. Unlike animals, which are governed largely by instinct, people are influenced by a variety of factors, ranging from love and other wholesome qualities to hatred and greedy self-interest.

Because humans seem increasingly to be ruled by the latter, many fear for the future of our planet. (2 Timothy 3:1-5) But they fail to take into account the Creator. The outworking of God’s purpose for the earth will not only restore a proper balance to nature but also result in unprecedented harmony among all creatures, including humans.

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A Dual Organism

Those crusty, gray or green blotches you often see on rocks and tree trunks are probably lichens. Some sources say there may be up to 20,000 varieties! Lichens may look like a single organism, but in reality they are a composite of a fungus and an alga.

Why do the two organisms unite? Funguses cannot produce their own food. So by means of microscopic threads, a fungus embraces an alga, which uses photosynthesis to make sugars. Some of these sugars leak out through the walls of the alga and are absorbed by the fungus. The alga, in turn, receives moisture from its host and is protected from excessive sunlight.

With a touch of humor, one scientist summed up lichens as “fungi that have discovered agriculture.” And they are good at it, for lichens, says the book Liaisons of Life, “cover ten times as much of the earth’s surface as tropical rain forests.” They live from the Arctic to the Antarctic and even thrive on the backs of insects!

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Coral​—A Marvel of Symbiosis

Coral reefs are made up of polyps and algas. Packed into every available spot in polyp cells, algas give corals their brilliant colors. And they often exceed the polyps in weight, sometimes by as much as 3 to 1, making corals more plant than animal! The algas’ main function, however, is to photosynthesize organic compounds, 98 percent of which they give to their host as “rent.” Polyps need this nutrition not just to survive but also to build reef-forming limestone skeletons.

The algas benefit from the alliance in at least two ways. First, they get food in the form of the polyps’ waste products​—carbon dioxide, nitrogen compounds, and phosphates. Second, they enjoy the protection of a tough skeleton. Algas also need sunlight; hence, coral reefs grow in clear, well illuminated water.

When coral is subjected to stress, such as a rise in water temperature, the polyps eject the algas and become bleached. Death by starvation may follow. In recent years scientists have observed an alarming increase in coral bleaching around the world.

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 A Lesson in Cooperation

Two jet aircraft flew across the sky like birds in tight formation. But this was not a routine flight; it was a scientific experiment based on earlier studies conducted on pelicans. Researchers had found that pelicans flying in formation gain extra lift from those ahead, resulting in a 15 percent reduction in heartbeat compared with their heartbeat when flying alone. Could aircraft benefit from the same aerodynamic principles?

In order to find out, engineers fitted a test plane with sophisticated electronics that enabled the pilot to keep his craft within a foot [30 cm] of a specific point relative to the lead plane, which was about 300 feet [90 m] ahead. (See picture.) The result? His jet experienced 20 percent less drag than normal and burned up to 18 percent less fuel. Researchers believe that these findings may have both military and civilian applications.

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Jets: NASA Dryden Flight Research Center; birds: © Joyce Gross

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In its rumen, a cow hosts a veritable ecosystem of bacteria, funguses, and protozoa (magnified inset)

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Inset: Melvin Yokoyama and Mario Cobos, Michigan State University

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Bees enable flowering plants to reproduce

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A cow with a cattle egret

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A butterfly fish with a small cleaner fish

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A spotted cleaner shrimp on an anemone