colony In zoology, a group of organisms of one species that live and interact closely with each other in an organized fashion. A colony differs from an aggregation, in which the group has no cooperative or organized function. Colonies of social insects (e.g., ants, bees) usually include castes with different responsibilities. Many birds form temporary breeding colo¬ nies, in some cases to stimulate reproductive activities, in others to make the best use of a limited breeding habitat and to coordinate efforts in pro¬ tecting nests from predators. Certain mammals that live in close groups are said to be colonial, though they lack cooperative activities and each maintains a territory.
Colophon \'ka-l3-,fan\ Ancient Ionian Greek city, western Anatolia. Located 15 mi (25 km) northwest of the ancient city of Ephesus, it was a flourishing commercial city in the 8th-5th centuries bc, famous for its cavalry, its luxury, and its production of rosin. A member of the Delian League, during the Peloponnesian War it was controlled first by the Per¬ sian Achaemenian dynasty and then by Athens, and it was conquered in 302 bc by Macedonia under Alexander the Great. Only a few foundations of the old walled city are now visible.
Colorado Group of Indian people of Ecuador’s Pacific coast. In the tropical lowlands where the Colorado traditionally have lived, they and the neighbouring Cayapas are the last remaining aboriginal groups. The Colorado (Spanish: “red”), so named because of their use of red pigment to decorate their faces and bodies, have been fishermen, hunters, and shifting cultivators; some, however, have taken up work on plantations, and others have migrated to work in the city.
Colorado State (pop., 2000: 4,301,261), west-central U.S. Bordered by Wyoming, Nebraska, Kansas, Oklahoma, New Mexico, and Utah, it cov¬
ers 104,100 sq mi (269,619 sq km); its capital is Denver. Lying astride the Rocky Mountains, the state has three physiographic regions: the plains, a semiarid segment of eastern Colorado; the Colorado Piedmont in the cen¬ tral part of the state, where most of the population lives; and the south¬ ern Rocky Mountains and mesas of western Colorado. Its large urban population has grown faster than the national average. Its original inhab¬ itants were Plains and Great Basin Indians, including the Arapaho, Chey¬ enne, and Ute. The area was claimed by Spain in 1706 but later passed in large part to France. Eastern Colorado was part of the Louisiana Purchase in 1803; the remainder stayed in Spanish and, after independence, Mexi¬ can hands until 1848. Gold was discovered in 1859 and touched off a population boom. Organized as the territory of Colorado in 1861, it achieved U.S. statehood in 1876. Agriculture, cattle production, and min¬ ing, as well as manufacturing, are important to the economy. Government military installations and service industries have become prominent, and tourism is a major source of the state’s income (see Aspen; Boulder; Vail).
Colorado National Monument Natural area, western Colorado, U.S. Established in 1911, the 32-sq-mi (83-sq-km) scenic area is known for its colourful, wind-eroded sandstone formations, towering monoliths, and steep-walled canyons. Petrified logs and dinosaur fossils have been found in the area. Rim Rock Drive skirts the canyon walls, which rise more than 6,500 ft (1,980 m).
Colorado potato beetle or potato bug Leaf beetle (Leptinotarsa decemlineata, family Chrysomelidae) native to western North America. It began feeding on the leaves of cultivated potatoes when the plants were introduced into western North America, and by 1874 it had become an important and widespread pest. It has a hemispherical body, about 0.4 in. (10 mm) long, and is orange-red or yellow, with black stripes on the wing covers. Depending on climate, potato beetles may produce one to three generations each year.
Colorado River River, south-central Argentina. Its major headstreams, the Grande and Barrancas rivers, flow southward from the Andes Moun¬ tains and meet to form the Colorado near the Chilean border. It flows southeastward across northern Patagonia and the southern Pampas. Its lower course splits into two arms that flow into the Atlantic Ocean south of Bahia Blanca. Its total length is about 530 mi (850 km).
Colorado River River, western Texas, U.S. It flows southeast 862 mi (1,387 km) through prairie, hill, and canyon country past Austin and across the coastal plain to enter Matagorda Bay. The river, the largest entirely within Texas, is the site of flood-control, power, irrigation, and recre¬ ational projects.
Colorado River River, North America. Rising in the Rocky Mountains of Colorado, U.S., it flows west and south 1,450 mi (2,330 km) to empty into the Gulf of California in northwestern Mexico. It drains a vast sector of the North American continent, about 246,000 sq mi (637,000 sq km). No other river in the world has cut so many deep trenches, of which the Grand Canyon is the largest and most spectacular. It is important for hydroelectric power and irrigation; more than 20 dams, including Hoover Dam, have been built on the Colorado River and its tributaries.
Colorado Springs City (pop., 2000: 360,890), central Colorado, U.S. Standing on a mesa near the eastern base of Pikes Peak, it was founded in 1871 as Fountain Colony and later renamed for nearby mineral springs. Growth followed the Cripple Creek gold strikes in the 1890s. Military installations gave further impetus to development: it is home to the North American Aerospace Defense Command (NORAD) and the U.S. Space Command, headquartered at Peterson Air Force Base (established 1942); Fort Carson (1942); and the U.S. Air Force Academy (1958). The Garden of the Gods, a natural park with red sandstone monoliths, is one of many scenic attractions.
colorectal cancer Malignant tumour of the large intestine (colon) or rectum. Risk factors include age (after age 50), family history of colorec¬ tal cancer, chronic inflammatory bowel diseases, benign polyps, physical inactivity, and a diet high in fat. Many of the symptoms are associated with abnormal digestion and elimination. Colorectal cancer is treated by surgery, chemotherapy, or radiation therapy.
colorimetry ^ko-lo-'ri-mo-treV Measurement of the intensity of electro¬ magnetic radiation in the visible spectrum transmitted through a solution or transparent solid. It is used to identify and determine the concentrations of substances that absorb light of a specific wavelength or colour accord¬ ing to Lambert’s law, which relates the amount of light absorbed to the
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colossal order ► Columban I 435
distance traveled through the absorbing medium, and Beer’s law, relating it to the concentration of absorbing substance in the coloured solution. A photocell is often used to measure the amount of light transmitted through a glass tube containing the solution to be analyzed; the result is compared with results from a similar tube containing solvent alone. Most elements and many compounds, in appropriately treated samples, may be identified by colorimetry or spectrophotometry, a closely related technique.
colossal order or giant order Architectural order in which the col¬ umns extend beyond one interior story, often through several stories.