The Thrill of Seeing Ants
for What They Are

WATCH A CHILD’S FACE WHILE SHE’S POKING AROUND IN A TIDAL pool, peering under a rotten log, or netting tadpoles in a pond. The joy of surprise and discovery is instantly visible. When my daughter Severn was three or four, she asked me how worms are able to move through the ground. I told her they simply eat soil at the front end and poo it out the back. “Oh,” she responded, “so dirt is worm-food?” And I could see a smile of delight at this new thought.

Charles Darwin shared Severn’s fascination with worms. When he heard someone had estimated that there were 53,767 worms per acre, Darwin is reported to have “figured the worm population swallowed and brought up ten tons of earth each year on each acre of land. Earthworms therefore were … constantly turning it inside out. They were burying old Roman ruins. They were causing the monoliths of Stonehenge to subside and topple.” Darwin concluded: “Worms have played a more important part in the history of the world than most persons would at first suppose.”

One of the pleasures of science journalism is learning something that clicks on a light, suddenly providing an entirely new perspective on things around us. For example, in the 1970s, the biologist Lynn Margulis suggested that structures called organelles, found within cells of complex organisms, are actually the evolutionary remnants of bacterial parasites.

She pointed out that organelles are able to reproduce within a cell and even possess DNA and distinct hereditary traits. So, Margulis proposed, organelles were once free-living organisms that invaded cells and were eventually integrated into the host. In giving up their independence, these bacterial relics received nourishment and protection from the host cell. Looking in the mirror now, I see a reflection of a community of organisms inhabiting trillions of cells aggregated as me.

In an interview for The Nature of Things, I once asked Harvard University’s eminent biologist Edward O. Wilson why ants are so successful. His entire career has been spent studying these ubiquitous insects, and he became animated with enthusiasm as he answered:

There are only a few tens of thousands of species of ants, compared with millions of other nonsocial insects, but they dominate the world. Their secret is superorganism. A colony of ants is more than just an aggregate of insects that are living together. One ant is no ant. Two ants and you begin to get something entirely new. Put a million together with the workers divided into different castes, each doing a different function—cutting the leaves, looking after the queen, taking care of the young, digging the nest out, and so on—and you’ve got an organism weighing about 10 kilograms [22 pounds], about the size of a dog, and dominating an area the size of a house.

The nest involves moving about 40,000 pounds [18,000 kg] of soil and sends out great columns of workers like the pseudopods of an amoeba, reaching out and gathering leaves and so on. This is a very potent entity. It can protect itself against predators. It can control the environment, the climate of the nest. When I encounter one of these big nests of leaf-cutter ants, I step back and let my eyes go slightly out of focus. And what you see then is this giant, amoeboid creature in front of you.

It was a thrilling description that made me think about ants in a very different way.

In 1992, scientists in Michigan made the astounding announcement that the network of mycelia, threadlike extensions of fungi found in the ground, could be derived from one individual, not an aggregate of different organisms. They reported a single organism that extended throughout 16 hectares (40 acres). Not long after, biologists in Washington reported a fungus covering 607 hectares (1,500 acres).

This fall I was filming in a grove of quaking aspen, the lovely white-barked trees whose leaves shimmer at the slightest puff of air. I learned that what I thought was a group of individual trees was, in fact, a single organism. Like a strawberry plant that can spread asexually by sending out runners that grow roots and sprout leaves, quaking aspen multiply vegetatively. From one tree, shoots may grow up from a root 30 meters (100 feet) away.

The aspen is another kind of superorganism that can exploit a diverse landscape—parts of the organism may grow in moist soil and share the water with other portions perhaps growing in mineral-rich soil higher up. In Utah, a single aspen plant made up of 47,000 tree trunks was discovered. It covered an area of 43 hectares (106 acres) and was estimated to weigh almost 6 million kilograms (13 million pounds).

We know so little about the varieties of species that exist and the specific attributes of individual organisms that we have endless opportunities for discovery. It is an exciting prospect to anticipate the delicious surprises that await us