Anzio \'ant-se-,6\ Seaport and resort town (pop., 2001 prelim.: 36,468) southeast of Rome, Italy. It was founded, according to legend, by Ante-
ias, son of Odysseus and Circe. It was a stronghold of the Volsci in the 5th century bc. Conquered by Rome in 338 bc, Antium (as it was then known) became a resort for wealthy Romans. Nero and Caligula were born there. Destroyed by the Saracens in the 9th-10th centuries, it remained virtu¬ ally deserted until 1698, when Pope Innocent XII built a new port nearby. In 1944 it was the scene of a bloody but successful amphibious landing by Allied forces during World War II.
ANZUS Pact officially Pacific Security Treaty Security pact for the South Pacific, signed in 1951 by Australia, New Zealand, and the U.S. (hence its acronym). The U.S. first suggested a pact to Australia in the wake of the U.S.-Japan Security Treaty and fears of Japanese rearmament. The signatories agreed to maintain a consultative relationship for their collective security. In the 1980s New Zealand refused to let ships carry¬ ing nuclear weapons dock at its ports; the U.S., refusing to identify its nuclear-armed ships, suspended its treaty obligations to New Zealand in 1986, and the treaty has since been nonoperative with reference to New Zealand.
aorta Artery that carries blood from the heart to all the organs and struc¬ tures of the body. Where the left ventricle opens into the aorta, a valve prevents backflow of blood into the heart. The aorta ascends from the heart, arches over it to the left, then descends into the trunk. Arteries branch off along its length until it divides at hip level into arteries that go to the legs.
aorta, coarctation of the Congenital disorder involving narrowing of a short section of the aorta’s arch over the heart. It causes a charac¬ teristic murmur, abnormally high blood pressure in the arms, and reduced blood flow to the abdomen, pelvis, and legs. It increases the workload of the left ventricle, which usually becomes enlarged. Surgical reconstruc¬ tion or replacement (depending on the person’s age) of the narrowed area is most effective in the young.
Aosta \a-'os-ta\ City (pop., 2001: 33,926), capital of Valle d' Aosta region, northwestern Italy. Located at the juncture of the Great and Little St. Bernard Pass roads through the Alps, it was a stronghold of the Salassi, a Celtic tribe subdued by the Romans in 25 bc. A Roman town was founded there by Augustus in 24 bc, and many Roman structures survive, including the walls, two gates, and a triumphal arch in honour of Augus¬ tus. Aosta was the birthplace of St. Anselm.
AP See Associated Press
Apache North American Indians of the southwestern U.S. Their name is a Zuni word meaning “enemy.” Most Apaches live on five reservations in Arizona and New Mexico, U.S. Culturally, the Apache are divided into Eastern Apache, which include the Mescalero, Jicarilla, Chiricahua, and
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Apamea Cibotus ► aphorism I 87
Lipan, and Western Apache, which include the Cibecue. The Eastern Apache were predominantly hunting and gathering societies, while their Western counterparts relied more on farming. Their ancestors had come down from the north, as is evident from their languages; Apachean lan¬ guages are distantly related to other Athabascan languages spoken in Canada. They settled the Plains, but with the introduction of the horse they were pressed south and west by the Comanche and Ute. They attempted to befriend the Spanish, the Mexicans, and later the U.S. In 1861, however, there began a quarter-century confrontation between U.S. military forces and the Apache and Navajo. The Apache wars were among the fiercest fought on the frontier. The last ended in 1886 with the sur¬ render of Geronimo. The Chiricahua Apache were evacuated from the West and held successively in Florida, Alabama, and Oklahoma. In the 2000 U.S. census some 57,000 people claimed sole Apache descent. See also Cochise.
Apamea Cibotus V.a-po-'me-o-si-'bo-tosX City of Hellenistic Phrygia, near modern Dinar, Turkey. The city was built by Antiochus I (Antiochus Soter) in the 3rd century bc on the Maeander (Menderes) River. Super¬ seding the fortress city of Celaenae, it was placed in a commanding posi¬ tion on the great east-west trade route of the Seleucid dynasty. In the 2nd century bc Apamea passed to the rule of the Roman Republic and Empire and became an important centre for Italian and Jewish traders. Declining after the 3rd century ad, it was captured by Turkish invaders in 1070 and there¬ after was destroyed by an earthquake.
apartheid \o-'par-,tat\ (Afrikaans: “apartness” or “separateness”) Policy of racial segregation and political and economic discrimination against non-European groups in South Africa. The term was first used as the name of the official policy of the National Party in 1948, though racial segregation, sanctioned by law, was already widely practiced. The Group Areas Act of 1950 established residential and business sectors in urban areas for each “race” and strengthened the existing “pass” laws, which required non whites to carry identification papers. Other laws forbade most social contacts between those of European descent and others, authorized segregated public facilities, established separate educational standards, restricted each group to certain types of jobs, curtailed nonwhite labour unions, denied nonwhite participation in the national government, and established various black African “homelands,” partly self-governing units that were nevertheless politically and economically dependent on South Africa. These so-called homelands were not recognized by inter¬ national governments. Apartheid was always subject to internal criticism and led to many violent protests, strikes, and acts of sabotage; it also received international censure. In 1990-91 most apartheid legislation was repealed, but segregation continued on a de facto basis. In 1993 a new constitution enfranchised blacks and other racial groups, and all-race national elections in 1994 produced a coalition government with a black majority. These developments marked the end of legislated apartheid, though not of its entrenched social and economic effects. See also Afri¬ can National Congress; racism.
apatite A member of the phosphate group of minerals, the world’s major source of phosphorus, found as variously coloured, glassy crystals, masses, or nodules. Much of it has a chemical composition approximat¬ ing Ca 5 (P0 4 ) 3 (F,Cl,OH). If not for its softness, apatite would be a popu¬ lar gemstone; some of the material found is clear, but it is fragile and difficult to cut and polish.
Apatosaurus Vo-.pa-to-'sor-osX Genus of giant herbivorous dinosaur, one of the largest land animals of all time. Apatosaurus lived between 147 million and 137 million years ago during the Late Jurassic and Early Cretaceous Periods in North America and Europe. It weighed as much as 30 tons and was as long as 70 ft (21 m), including the very long neck and tail. Formerly known as Brontosaurus because of incomplete fossil evi¬ dence, its head was depicted until 1978 as massive and snub-nosed, with spoonlike teeth; scientists now know the animal had a slender, elongated skull and long, peglike teeth. Skeletal evidence indicates that, despite their great bulk, apatosaurs were primarily land animals.
ape Any of the tailless primates known as the lesser apes (gibbons and siamangs; family Hylobatidae) or the great apes (chimpanzees, bonobos, orangutans, and gorillas; family Hominidae). Apes are found in the tropi¬ cal forests of western and central Africa and South Asia. They are distin¬ guished from monkeys by having no tail, having an appendix, and having a more complex brain. Apes typically move about by swinging or knuckle- walking, though they are capable of standing erect and occasionally walk