(0.5-2 mm) long. The largest spe¬ cies, a parasite of the fin whale, grows to a length of about 13 in. (32 cm). Unlike most crustaceans, cope- pods have no carapace. Nonparasitic forms feed on microscopic plants or animals or even on animals as large as themselves. Members of the genus Cyclops (order Cyclopoida) are called water fleas. See also guinea worm.
Copernican Vka-'psr-ni-ksnV system or Copernican principle
Model of the solar system centred on the Sun, with Earth and other plan¬ ets revolving around it, formulated by Nicolaus Copernicus in the mid 16th century. Having the Sun in this central position explained the apparent motion of planets relative to the fixed stars and was truer than the Earth- centred Ptolemaic system (see Ptolemy). Scientifically, the Copernican sys¬ tem led to belief in a much larger universe than before (because, if the Earth revolved around the Sun, the stars would have to be very distant not to appeal - to alter their position); more broadly, the Copernican prin¬ ciple is invoked to argue against any theory that would give the solar sys¬ tem a special place in the universe. Dethronement of Earth from the centre of the universe caused profound shock: the Copernican system challenged the entire system of ancient authority and required a complete change in the philosophical conception of the universe.
Copernicus Vka-'psr-ni-kssV Nicolaus Polish Mikotaj Kopernik
(b. Feb. 19, 1473, Torun, Pol.—d. May 24, 1543, Frauenburg, East Prus¬ sia) Polish astronomer. He was educated at Krakow, Bologna, and Padua, where he mastered all the knowledge of the day in mathematics, astronomy, medicine, and theology. Elected a canon of the cathedral of Frauenburg in 1497, he took advantage of his financial security to begin his astronomical observations. His publication in 1543 of Six Books Con¬ cerning the Revolutions of the Heavenly Orbs marked a landmark of Western thought (see Copernican system). Copernicus had first conceived of his revolutionary model decades earlier but delayed publication because, while it explained the retrograde motion of the planets (and resolved their order), it raised new problems that had to be explained, required verification of old observations, and had to be presented in a way that would not provoke the religious authorities. The book did not see
Mud hen (Fulica americana)
BENJAMIN GOLDSTEIN FROM ROOT RESOURCES-EB INC.
Stela with portrait sculpture, Copan, Honduras.
WALTER AGUIAR/EB INC.
Copepods (Temora)
DOUGLAS P. WILSON
© 2006 Encyclopaedia Britannica, Inc.
copier ► copyright I 463
print until he was on his deathbed. By attributing to Earth a daily rota¬ tion around its own axis and a yearly revolution around a stationary Sun, he developed an idea that had far-reaching implications for the rise of modern science. He asserted, in contrast to Platonic instrumentalism, that astronomy must describe the real, physical system of the world. Only with Johannes Kepler was Copernicus’s model fully transformed into a new philosophy about the fundamental structure of the universe.
copier See photocopier
Copland Vko-pbndX, Aaron (b. Nov. 14, 1900, Brooklyn, N.Y., U.S.—d. Dec. 2, 1990, North Tarrytown, N.Y.) U.S. composer. Bom to Russian-Jewish immigrant parents, he studied composition in Paris with Nadia Boulanger. In his early works he experimented with jazz rhythms and then with an abstract style influenced by Neoclassicism. After the mid-1930s he was concerned with making music accessible to a wider audience and adopted notably American traits in his compositions. Famously public-spirited and generous, he came to be unofficially regarded as the U.S.’s national composer. He is best known for his three ballets based on American folk materiaclass="underline" Billy the Kid (1938), Rodeo (1942), and Appalachian Spring (1944, Pulitzer Prize). He also wrote film scores, orchestral works, and operas. In his later years Copland refined his treatment of Americana, making his references less overt, and he pro¬ duced a number of works using the experimental technique of SERIALISM. He continued to lecture and to conduct through the mid-1980s.
Copley, John Singleton (b. July 3, 1738, Boston, Mass.—d. Sept. 9, 1815, London, Eng.) U.S. painter of portraits and historical subjects. The stepson of an engraver, he was an accomplished draftsman before age 20 and flourished as a portrait artist in his native Boston. He was famous for his portraits d’apparat, portrayals of his subjects with the objects asso¬ ciated with them in their daily lives or professions. In 1775 he settled in London and turned to the more fashionable history painting; he was elected to the Royal Academy in 1779. He revealed a gift for portraying heroic action in multifigure compositions. He is considered the greatest U.S. painter of the 18th century and the finest artist of the colonial era.
copper Metallic chemical element, one of the transition elements, chemi¬ cal symbol Cu, atomic number 29.
Sometimes found in the free state in nature, it is a reddish metal, very duc¬ tile and an unusually good conduc¬ tor of electricity and heat. Most of the world’s copper production is used by the electrical industries; the remainder is combined with other metals (e.g., zinc, tin, nickel) to form alloys such as brass, bronze, nickel silver, and Monel. Copper is part of nearly all coinage metals. In com¬ pounds copper usually has valence 1 (cuprous) or 2 (cupric). Cuprous compounds include cuprous oxide, a red pigment and a fungicide; cuprous chloride, a catalyst for certain organic reactions; and cuprous sulfide, with a variety of uses. Cupric compounds include cupric oxide, a pigment, decolorizing agent, and cata¬ lyst; cupric chloride, a catalyst, wood preservative, mordant, disinfectant, feed additive, and pigment; and cupric sulfate, a pesticide, germicide, feed additive, and soil additive. Copper is a necessary trace element in the human diet and essential to plant growth; in blue-blooded mollusks and crustaceans it plays the same role in hemocyanin as iron does in hemo¬ globin.
copper (butterfly) Any member of the butterfly subfamily Lycaeninae (family Lycaenidae). Coppers are common and widely distributed. Adults, sometimes known as gossamer-winged butterflies, are delicate, with a wingspan of 0.75-1.5 in. (18-38 mm). They are rapid fliers, usually with iridescent wings. Coppers typically range from orange-red to brown, usu¬ ally with a copper tinge and dark markings. Copper larvae feed on clo¬ ver, dock, or sorrel.
Copper Age First part of the Bronze Age. The beginning of the period is sometimes called the Chalcolithic (Copper-Stone) Age (c. 8000 bc), referring to the initial use of copper ore. Sometime after 6000 bc, smelt¬ ing ore to produce pure copper was discovered in Anatolia (Turkey). From 5000 bc copper metallurgy, with cast tools and weapons, was a factor
leading to urbanization in Egypt and Mesopotamia. Copper metallurgy spread to India by 3500 bc and to Europe and China by 3000 bc. Copper ore occasionally contains tin, which makes dating bronze metallurgy dif¬ ficult. The Bronze Age began c. 3500 bc in the Middle East and spread throughout the Old World between 3000 and 1800 bc. The Copper Age began in the New World c. ad 100 and the Bronze Age c. 1000.
Copperhead Term used during the American Civil War to describe a Northerner who opposed the war policy and favoured a negotiated settle¬ ment with the South. The term was first used in 1861 by the New York Tribune, referring to the copperhead snake that strikes without warning. Most Copperheads (also called Peace Democrats) were from the Midwest, where agrarian interests distrusted the growing federal power. The move¬ ment’s leaders included Clement Vallandigham. Though the movement was unable to influence the conduct of the war, Republicans used the Cop¬ perhead label to discredit the Democratic Party.
copperhead Any of several unrelated species of snake named for their reddish head. The North American copperhead ( Agkistrodon contortrix), also called the highland moccasin, is a pit viper of swampy, rocky, and wooded regions of the central and eastern U.S. It is usually less than 3 ft (1 m) long and is pinkish or reddish with a copper-coloured head and reddish brown, often hourglass-shaped crossbands on its back. Its venom is relatively weak, and a bite is rarely fatal to humans. The Australian copperhead is an eiapid, and the Indian copperhead is a rat snake.