Super ant territory

Argentine ants are making the US their home. Biologists of the University of California in San Diego ( uscd ) have discovered the biggest colony of ants -- more than 1,000 kilometres long -- stretching from San Diego to the north of San Francisco. Argentine ants belonging to different colonies generally fight among themselves in their homeland. But they are behaving like a single united family in California. This has led to the emergence of the supercolony. "When we did our field work in Argentina, it was surprisingly difficult to find the ants, compared to our experience in California," says Ted J Case, a professor of biology at uscd . "They are a relatively inconspicuous feature, both in the urban and rural areas of Argentina," he added. But in California, especially in the southern parts of the state, the Argentinean ants are being regarded as the number one pest. "They have invaded houses, gardens and offices," says N D Tsutsui, a student at uscd. These ants have also displaced native ant species. Besides this, their growth is also creating problems for species that feed on the native ant species. These ants are thought to have entered the US aboard ships carrying sugar from Argentina in the 1890s.