Secret Lives of Ants

11. Villains and Monsters of the Ant World: Predators and Parasites

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 predators and parasites 11 Villains and Monsters of the Ant World Many different insects fall prey to birds, lizards, spiders, and carnivorous plants such as sundews and Venus flytraps. But some predators specifically prey on ants. The larva of the antlion is an interesting example. In its adult stage, it is a flying insect that looks similar to a dragonfly, but it gets its name from its habit of viciously preying on ants during its larval stage. While assassin bugs—an ant predator that we met earlier —go to ant nests to prey on ants, antlions dig pit traps and wait for unwitting insects, especially ants, to fall in. Antlion larvae dig funnel-shaped pit traps in sandy places and hide under the sand at the bottom to wait for their prey. The larva digs the walls of the pit at just the right angle. Once an ant makes the mistake of setting foot in the antlion ’s pit trap, it triggers a miniature landslide and the hapless ant falls to the bottom of the pit. The antlion, awaiting its victim, kicks sand away from the bottom, adding to the avalanche and sealing the ant’s fate. No matter how hard the ant struggles, there is no escape. The antlion does not pounce on the ant as soon as it falls into the pit, preferring to wait until the ant is exhausted from its desperate attempts to escape. Then the antlion larva rears its massive-jawed head. According to Nick Gotelli of the University of Vermont there are places in Oklahoma that have clusters of hundreds and even thousands of antlion pit traps, each with an antlion larva waiting at the bottom. Places like this must be the stuff of ant nightmares. 90 A queen ant trapped on the leaf of sundew, an insectivorous plant. A jumping spider feasting on an ant. Opposite, A pit trap dug at the perfect angle. The antlion that dug the trap is waiting at the bottom for ants to fall in. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v i l l a i n s a n d m o n s t e r s o f t h e a n t w o r l d 91 The Dragon of the Ant World Ants in many different tropical regions of the world must live with the constant menace of several kinds of mammal that feast on ants. In Africa they have to contend with aardvarks (with a name like that, first in the dictionary); another species of African anteater uses its sturdy claws to dig up ant nests and then snake its long, sticky tongue deep into the tunnels, slurping up ants. Vested anteaters, named for the black fur that covers their shoulder and stomach areas like furry vests, live on Barro Colorado Island in Panama, where I did extensive field research. Whenever I ran into an anteater, the startled creature would rear back on its hind legs, brandishing its front claws and squealing at me, trying to look threatening. I could not help but find them cute and a little bit silly, although for ants anteaters are a force to be reckoned with. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . t h e c u l t u r e o f a n t s o c i e t y 92 Most species of ants in those regions actually have more to fear from one of their own kind, however; namely, the army ants. While anteaters’ tongues usually cannot reach the queen’s chamber of most ant nests, if ants make the mistake of letting army ants into their queen’s chamber or their nursery, the army ants will not hesitate to tear apart and consume everything they find there. I witnessed ruthless army ants invading many of the nests of other ant species. Each time I saw one of these attacks, I could not help but admire the way the invaded ants heroically held their ground to defend their colonies. Solzhenitsyn would have been impressed by their sacrificial acts. The Porcupine of the Ant World Beware the prickly porcupine! Many animals and humans have regretted making the mistake of disturbing one. The late Thomas Eisner of Cornell University has reported that there is an ant equivalent of the porcupine. This is a type of polychaete, or bristle worm, that defends itself from ants by squirming out of their grasp and covering the ants’ bodies with bristles. The...