Ant colony

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A plaster cast of an ant nest.
Entrance to a Harvester Ant nest (Pune, Maharashtra, India)

An ant colony is the basic family unit around which ants organize their lifecycle.[citation needed] Ant colonies are eusocial, and are very much like those found in other social Hymenoptera, though the various groups of these developed sociality independently through convergent evolution.[citation needed] The typical colony consists of one or more egg-laying queens, a large number of sterile females ("workers") and, seasonally, a large number of winged sexual males and females.[citation needed] Periodically, swarms of the winged sexuals (known as alates) depart the nest in great nuptial flights. The males die shortly thereafter, along with most of the females.[citation needed] A small percentage of the females survive to initiate new nests.[1]

Supercolonies[edit]

Until 2000, the largest known ant supercolony was on the Ishikari coast of Hokkaidō, Japan. The colony was estimated to contain 306 million worker ants and one million queen ants living in 45,000 nests interconnected by underground passages over an area of 2.7 km2 (670 acres).[2] In 2000, an enormous supercolony of Argentine ants was found in Southern Europe (report published in 2002). Of 33 ant populations nested along the 6,004-kilometre (3,731 mi) stretch along the Mediterranean and Atlantic coasts in Southern Europe, 30 belonged to one supercolony with estimated millions of nests and billions of workers, interspersed with three populations of another supercolony.[3] The researchers[which?] claim that this case of unicoloniality cannot be explained by loss of their genetic diversity due to the genetic bottleneck of the imported ants.[citation needed] In 2009, it was demonstrated that the largest Japanese, Californian and European Argentine ant supercolonies were in fact part of a single global "megacolony".[4]

Another supercolony, measuring approximately 100 km (62 mi) wide, was found beneath Melbourne, Australia in 2004.[5]

Organizational terminology[edit]

The following terminology is commonly used among myrmecologists to describe the behaviours demonstrated by ants when founding and organizing colonies:[1]:page 209

Monogyny 
An ant colony established under a single, egg-laying, queen.
Polygyny 
An ant colony established under multiple, egg-laying, queens.
Oligogyny 
A polygynous colony where the multiple, egg-laying, queens remain far apart from one another in the nest.
Haplometrosis 
The founding of a colony by a single queen.
Pleometrosis 
The founding of a colony by multiple queens.
Monodomy 
An ant colony established in a single nest site.
Polydomy 
An ant colony occupying multiple nest sites.

Ant-hills[edit]

A clay ant hill

An ant-hill, in its simplest form, is a pile of earth, sand, pine needles, or clay or a composite of these and other materials that build up at the entrances of the subterranean dwellings of ant colonies as they are excavated. A colony is built and maintained by legions of worker ants, who carry tiny bits of dirt and pebbles in their mandibles and deposit them near the exit of the colony. They normally deposit the dirt or vegetation at the top of the hill to prevent it from sliding back into the colony, but in some species they actively sculpt the materials into specific shapes, and may create nest chambers within the mound.

See also[edit]

References[edit]

  1. ^ a b The Ants, Bert Holldobler and Edward O. Wilson, Harvard University Press, 1990, ISBN 0-674-04015-9
  2. ^ Higashi, S. and K. Yamauchi. Influence of a Supercolonial Ant Formica (Formica) yessensis Forel on the Distribution of Other Ants in Ishikari Coast. Japanese Journal of Ecology, No. 29, 257-264, 1997.
  3. ^ Tatiana Giraud, Jes S. Pedersen, and Laurent Kelle. Evolution of supercolonies: The Argentine ants of southern Europe. The National Academy of Sciences, 2002.
  4. ^ Ant mega-colony takes over world BBC Wednesday, 1 July 2009 10:41 GMT.
  5. ^ Super ant colony hits Australia. BBC News, 2004.

External links[edit]