Adventures Among Ants - Mark W. Moffett [8]
While I was in the entomologist’s “compromising position,” my nose practically brushing the frenzied ant workers that scurried beneath me, a young man of about my age walked up. Oblivious to my rapture over the ants, he started a conversation by saying his name was Rajaram Dengodi, which he explained meant “King God of All Mankind,” and inviting me for lunch. It turned out he was the son of the plantation owners and lived with his parents at the edge of the palm grove. When I arrived at their low whitewashed house, he proclaimed that I’d be sharing his room for the month.
Despite the grandeur of his name, Raja was a low-key fellow with no apparent ambition other than to strum his guitar. But he proved an admirable companion and was eager to learn about ants. During that first week, I mapped the plantation and decided where to concentrate my search. Then Raja and I set about following the activities of the local Pheidologeton diversus. It quickly became evident that the colonies were huge. We saw several migrations with dense legions of ants moving their larvae and pupae to new nest sites, which suggested the workers numbered in the hundreds of thousands.
We also witnessed the hunting and harvesting of meals on a massive scale. The workers carrying food moved along well-demarcated roads that remained active day after day. In time, I would learn that these tracks had as many functions as human road systems. Ant specialists call such persistent routes trunk trails. The marauder ant’s trunk trails are substantial structures, with a smooth surface an inch wide. Along them, the ants craft soil walls or even a complete roof of soil. The trails frequently lead belowground, especially where they cross dry or exposed stretches of earth.
Hundreds of ants, and sometimes more, crossed back and forth on those trails every minute. In one extreme case I recorded eight thousand workers per minute climbing a cacao tree to flow into and out of a rotten pod over the course of a full day. Marauder ants excel at plundering large foods, such as fruit or carcasses, that take them a while to devour. But these expeditions represent only a small portion of their efforts. At any time, day or night, I could see them traveling from the trunk trails in ever-changing, reticulating networks, or, as Captain Bingham described them in Burma, in swarms. These extended into vegetation and leaf litter, where the ants’ activities were hard to document.
I confirmed the observations of early naturalists that marauder ants can harvest seeds in bulk. More impressive, the ants returning to the nest labored by the dozen to cart centipedes, worms, and other creatures that, if viewed through ant eyes, would appear bigger than dinosaurs to us. A few dozen minor workers, each about 3 millimeters long, easily hefted the head of one of the doves the Dengodis had tried to induce me to eat after they found out Americans eat meat. Later, Raja and I saw a seething mass of workers rip up a live, 2-centimeter-long frog, pulling its twitching body taut to the ground and then flaying the meat. Raja and I studied the action with both horror and a newfound respect. That was the day I named them marauder ants.
Marauder ants subduing a frog in southern India.
Though Sullia was in no danger from the ant swarms, it was easy to believe Bingham’s report from Burma that droves of this species could overwhelm a village. Raja enthusiastically told me how the ants would sometimes pour into the family pantry and make off with supplies of rice and dried condiments.
At dinner we reported to Raja’s parents about the marauders’ feats of predation, which I described as astonishing, particularly because the workers have no stinger, the weapon with which many predatory ants—especially those species in which the workers carry on alone or in small groups—disable victims. Mr. and Mrs. Dengodi, who took everything I said with great seriousness, no matter how eccentric the subject, listened