English: These termite mounds were most impres...
English: These termite mounds were most impressive. From the park sign: Cathedral Termite Mound This mound is home to a colony of grass eating termites, Nasutitermes triodiae. It's about 5 meters high and could be over 50 years old. Kingdom:Animalia Phylum:Arthropoda Class:Insecta Subclass:Pterygota Infraclass:Neoptera Superorder:Dictyoptera Order:Isoptera Family: Termitidae Litchfield National Park, Northern Territory, Australia i09_0501 027 (Photo credit: Wikipedia)
This is definitely a science feature, but there is something to learn, especially for leaders. We don't always get to give. It is what we are, how we do, and where we thrive. That will spell our survival for the next milleniums to come...
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By NATALIE ANGIER


The giant termite mounds that rise up from the sands of the African savanna are so distinctive it is tempting to give them names, like “Trumpeting Elephant” or “Flagrantly Obvious Fertility Totem.”

Whatever the metaphor, the megaforms dominate their landscape, and not just visually. As scientists are just beginning to appreciate, termites and their habitats are crucial to the health and robustness of an array of ecosystems: from deserts to rain forests to your local park.

Researchers at Princeton University in New Jersey reported in the journal Science that termite mounds may serve as oases in the desert, allowing the plants that surround them to persist on a fraction of the annual rainfall otherwise required and to bounce back after a withering drought. The mounds could prove potential bulwarks against climate change, preventing fragile dryland from slipping into lifeless wasteland.

“Even when you see desertification start to happen between the mounds, the vegetation on or around the mounds is doing so well it will keep reseeding the environment,” said Corina Tarnita, a professor at Princeton and an author of the report.

While the public may view termites as pale, blind, centimeter-long vermin that can damage homes, only a handful of the 3,000 or so known termite species are pests to people. Many of the rest, you can thank for the ground beneath your feet, which is where the majority live and work. The closer scientists look, the longer grows the list of subterranean tasks that termites take on.

“They’re the ultimate soil engineers,” said David Bignell, an emeritus professor at Queen Mary University of London.

By poking holes as they dig, termites allow rain to soak deep into the soil rather than run off or evaporate. Termites mix sand, stone and clay with organic bits of leaf litter, discarded exoskeletons and the occasional squirrel tail, a blending that helps the soil retain nutrients and resist erosion.

The stickiness of a termite’s feces and other bodily excretions lends structure and coherence to the soil, which also prevents erosion. Bacteria in the termite’s gut can fix nitrogen, extracting it from the air and converting it into a fertilizer, benefiting the termite host and the vast underground economy. “Over all, termites are extremely good for the health of the soil” on which everything else depends, Dr. Bignell said.

Termites also provide a model for understanding the origins of social life, the division of labor, and a sort of altruistic, self-abnegating behavior. In a new study of “panic escape” behavior among termites as they seek to flee from danger, researchers at Louisiana State University Agricultural Center determined that the one thing the termites do not do when disturbed is panic. They don’t start running, pushing and shoving, or clambering over the fallen. They don’t behave like people in a crowded theater when somebody yells fire, or like ants whose nest has been harrowed.

Instead, the researchers found that when they placed 110 termites on round plastic dishes and gave the plates a shake, the termites started running in an orderly fashion, depending on whether they were ordinary workers or soldiers dedicated to nest defense. The workers fell into single-file formation. The ones infront decided whether to turn left or right, and the rest followed at a uniform speed and spacing.

The soldiers migrated to either side of the flow, snapping their mandibles as though preparing to do battle. If one termite stumbled or slowed, those behind would stop and wait for it to right itself.

That organization distinguishes termites from their more famous counterparts among social insects, the ants. “Ants will crowd over each other and get trapped at exits or intersections,” said Gregg Henderson, an entomologists at the agricultural center and an author of the report, which appeared in the journal Insect Science. “But I’ve seen no evidence of selfishness in termites.”

That may be because they have had a lot of practice. Termites, Dr. Henderson said, “were the first animals to form societies,” starting about 200 million years ago, some 50 million years earlier than the ants and their hymenopteran cousins, the bees.

With the help of symbiotic bacteria and protozoa packed into their stomachs at what might be the highest microbial densities in nature, termites thrive by eating what others can’t or won’t: wood, dung, even dirt.

The great termite artists of Africa, the mound builders, cultivate a fungus in tunnels and galleries deep inside vast palaces built of sand, clay and termite excretions. The termites eat a small portion of the fungal spores and use the fungal enzymes to help break down fibrous food sources.

The termites, in turn, offer their fungal partners water, nourishment and a temperate and well-ventilated haven free of competing fungal strains. The mounds also protect their builders against the sun, the seasonal rain and predators.

The largest African mounds can measure nine meters high and house millions of termites. In Mozambique’s Gorongosa National Park, antelope congregate around termite mounds, and not just for the grazing opportunities.

“The mounds are cooler in the heat of day and warmer at night,” said Robert Pringle, an ecologist at Princeton and an author of the report in Science. “They’re a very pleasant place to hang out.”


Taken from TODAY Saturday Edition, The New York Times International Weekly, March 14, 2015

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