Slave-making ants rob cradle.Driven by hunger and guided by the sun, swarms of red western ants indugle in daring kidnapping raids against a neighboring neigh·bor n. 1. One who lives near or next to another. 2. A person, place, or thing adjacent to or located near another. 3. A fellow human. 4. Used as a form of familiar address. v. species. So reports Howard topoff, a psychologist at Hunter College Hunter College: see New York, City University of. in New York City New York City: see New York, city. New York City City (pop., 2000: 8,008,278), southeastern New York, at the mouth of the Hudson River. The largest city in the U.S. , who has been analyzing the behavior of the western slave-making ant slave-mak·ing ant n. Any of various species of ant, such as Formica sanguinea of Europe, that raid the nests of other ants and carry off the pupae in order to provide workers for their own colony. Noun 1. , Polyergus breviceps Polyergus breviceps is a species of insect in family Formicidae. It is endemic to the United States. Source
These ants are dependent for survival on their slaves, a related species Formica gnava. The slaves are captured young, as pupae, and they emerge as adults in the slave-makers' nest. The slaves forage, defend the nest and feed and groom their masters. If the colony relocates, they carry the slave-makers one by one to the new site. A colony of 3,000 slave-making ants may have more than 6,000 slaves. Topoff has observed the events leading to the capture of pupae. First, scouts search for Formica nests. A successful scout returns to its colony and uses tactile and chemical means to recruit raiders. The swarm of raiders may number 2,500, and advance in a phalanx phalanx, ancient Greek formation of infantry. The soldiers were arrayed in rows (8 or 16), with arms at the ready, making a solid block that could sweep bristling through the more dispersed ranks of the enemy. 3 feet wide and 16 feet long. Topoff finds that the scout and its followers rely on sun position, as well as on a chemical trail previously left by the scout, to find their way. With a mirror held to change the apparent position of the sun, Topoff can make the raiding party reverse direction. When the slave-makers reach the target nest, they spray it with a chemical that forces the Formica adults to flee, leaving behind most of the young. The raiders then capture thousands of pupae, some to eat and others to raise as slaves. A single Polyergus colony may steal as many as 30,000 Formica pupae each year. Topoff finds that need for food is a stimulus for the raids. If he overfeeds a colony, kidnapping raids become less frequent. |
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