Be Careful of Little Lives
Go to the ant, you sluggard; consider her ways and be wise:
Which, having no chief, overseer, or ruler,
Provideth her meat in the summer, [and] gathereth her food in the harvest.
Scripture praises ants, children are mesmerized by them, and yet ants in the garden are so commonplace as to be easily ignored by us adults. That however, would be a lost opportunity. Ants provide us a chance to witness the spectacle of miniature empires rising and falling in our own backyard.
It is not news that an individual ant is possessed of amazing physical abilities for its size. Scientists have put weaver ants upside down on glass where they can not only hold on but support 100 times their own weight. (Their secret is a liquid secreted from their feet.) However, ants don’t come into their glory as individuals; they all live in colonies and it is here that they shine.
There are ant colonies numbering only a few hundred individuals that fit into a single acorn (Temnothorax longispinosus) and others that include millions of individuals living in vast subterranean cities. One such grasscutter ant megalopolis was found abandoned in Argentina. Scientists pumped concrete into the entrances for days and when dry they carefully dug away the surrounding dirt. What they found was astonishing, a vast city where the ants had removed over forty tons of soil. It featured pathways and chambers that stretched down over 25 feet below ground. All accomplished without a central authority directing the activity.
It is easy to get swept away by the shock and awe of statistics, but it is the myriad ways that ants make a living that fascinates me. There are ant societies who make their communal living as farmers, ranchers, hunters and even slave raiders. One stormy July afternoon I discovered the hidden kingdom of the citronella ants, but that is a story for later.
Due to their complexity, ant societies are often thought of as the closest to human societies. And, like human societies, they have gone from strict hunters and gatherers to agriculturalists. Some of the most successful ants farm fungus in underground gardens. They feed their fungus grass or leaves harvested from their surroundings. Most amazing is that the fungus exists nowhere else in nature, besides the ants’ guts and their fungus gardens, and the ants must fight off other types of fungus and bacteria that threaten these gardens. They do this by applying their own form of antibiotics to any newly added plant material. They also have created ventilation systems that cleverly draw in fresh air and vent out carbon dioxide. This system is so efficient that over five million individuals may occupy a single colony.
There are not only farmers in the ant world, but ranchers as well. Their “livestock” are mealy bugs and aphids. These insects suck the sap from plants and then excrete excess sugar which the ants lap up. The ants in return protect their charges from predators and even hide them under leaves during rain. The ants pick up and move their livestock to “fresh pastures,” parts of the plants with more, and/or sweeter, sap. When the ants move they take their livestock with them.
Some ant societies have a more martial flair. They are highly mobile “armies” moving the entire colony on a regular basis, looking for fresh hunting grounds. These “army ants” not only feed themselves, hunting anything they can overpower, but many species of birds make a living following the ants around as well. Insects fleeing the ants are then snapped up by the birds. In fact there is a whole family of antbirds, Thamnophilidae, with over 200 members. There are antwrens, antshrikes, antvireos and the list goes on. Clearly it is a successful strategy to follow around hunting colonies of army ants.
Pushing the edge of the fantastic is the story of various slave raider ants. These ants raid other ant colonies and steal their eggs and pupae. They return to their own nests and tend the captives. When these captives are born, they are so immersed in the chemical cocktail of their captors’ colony that they assume they belong. Some slave raiders have become such specialized warriors that they can no longer take care of themselves. They rely completely on their slaves to gather food and even to feed them. One example from the United States, Polyergus breviceps, won’t even clean up after themselves or feed their queen without ant slaves from the genus Formica.
Colorado’s “monsoon” season provides the backdrop to a tale of intrigue and power. To tell that tale I must return to the citronella ants. Great thunderstorms erupt in July and August dumping torrential rains. Many animals depend upon these rains, including ants. One July afternoon, out hiking in our neighboring Garden of the Gods Park, I came across small, uneven holes in the dirt. Clustered around the entrance were tiny, exquisitely golden ants. I had never seen anything quite like them. Days later I came back and they were gone.
It would be another year before I had the chance to unravel this little local mystery. This time, as thunderheads again threatened, not only did I rediscover the golden ants, but small black winged ants poured out of the misshapen holes. I then started noticing larger, solitary reddish colored ants running around in the same area. One found a hole and, bypassing the golden and winged black ants, disappeared down it. I took pictures and started sending them off to myrmecologists, ant scientists, hoping someone would have a clue as to what was going on.
Turns out these ants are known as citronella ants, Lasius latipes, (they have an alarm pheromone that smells strongly of citronella). They are completely subterranean except during the monsoon season when the reproductive winged males and larger virgin queens take off for their nuptial flights. The black males die shortly after mating, their role in the story over. The queens’ stories, however, are just beginning. After landing they rub off their wings, and unlike other ant queens, they don’t build their own nest but rather plot a coup.
The queen I observed stealing into the nest was on a mission. Most likely she was from another species of Lasius ant. Wafting her own chemical scent, she would seek to woo the small golden female workers while hunting the resident queen. If successful, she would kill the reigning monarch and take over egg laying duties, her offspring slowly replacing those of the former queen. All the ants will return underground, regardless of the success or failure of the coup attempt, and continue their existence, herding their aphids and scale insects who feed on sap from plant roots. The entire colony and their “livestock” won’t visit the light of day again until the monsoons return again next year.
In our gardens, ants are the great equalizers. By hunting insects that become temporarily more populous, they make sure no one group of insects gets out of hand. Their tunnels aerate soil and allow water to penetrate more easily. They have been around for over 100 million years and have formed complex relationships in the environment, many of these we are still discovering. So should you find ants in the garden, relax, they belong there. If you should find them in the house, remember the words of perhaps the most famous ant scientist, Nobel Prize winner E.O. Wilson. When asked what to do if you find ants in your kitchen, Wilson replied, “Be careful of little lives.”
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DB Rudin is a freelance writer, teacher and environmental activist. He is currently the Education Coordinator at Venetucci Farm and Pinello Ranch ( http://www.venetuccifarm.org ) projects of the Pikes Peak Community Foundation ( www.ppcf.org ). David has been a columnist for Manitou Magazine and, most recently, Greenwoman Magazine. He is an avid birder and also has strong interests in herpetology and entomology. He lives near Garden of the Gods Park with his wife Margaret and their dogs, Gracie and Benny. He can be reached at email@example.com. His blog, A Naturalist’s Journal, can be found here: https://naturethroughtheseasons.wordpress.com/