zombi In Vodou, a dead person who is revived after burial and com¬ pelled to do the bidding of the reviver, including criminal acts and heavy manual labour. It is believed that actual zombis are living persons under the influence of powerful drugs, including burundanga (a drug reportedly used by Colombian criminals) and drugs derived from poisonous toads and puffer fish.
zone melting Any of a group of techniques used to purify an element or a compound or to control its composition by melting a short region (called a zone) and causing this liquid zone to travel slowly through a relatively long ingot, or charge, of the solid. In zone refining, the most important of the zone-melting techniques, a solid is refined by multiple molten zones being passed through it in one direction. Each zone carries a fraction of the impurities to the end of the solid charge, thereby puri¬ fying the remainder. Zone refining is particularly important as a method of purifying crystals, especially for use in semiconductor devices.
zone of avoidance See avoidance, zone of
zoning Legislative method of controlling land use by regulating consid¬ erations such as the type of buildings that may be erected and population density. German and Swedish cities first applied zoning regulations in the late 19th century to address the problems of urban congestion and building height. The earliest U.S. zoning ordinances, which date from the beginning of the 20th century, were motivated by the need to regulate the location of commercial and industrial activities. In 1916 New York City adopted the first comprehensive zoning law; it and other early regulations were designed to protect property values and preserve light and air. Modern zon¬
ing regulations divide land use into three types: residential, commercial, and industrial. Within each designation, more specific aspects of develop¬ ment (e.g., building proximity, height, and type) are also determined. Zon¬ ing is often used to maintain the distinctive character of a town or city; an adverse consequence of such zoning is economic segregation. The Supreme Court of the United States ruled against such laws in 1977 when it declared the zoning regulations of one Chicago suburb discriminatory.
zoo or zoological garden Place where wild and sometimes domes¬ ticated animals are exhibited in captivity. Aquatic zoological gardens are called aquariums. The first zoos were perhaps associated with domesti¬ cation. Pigeons were kept in captivity as early as 4500 bc; other animals (e.g., elephants and antelopes) have also been kept in captivity since antiquity. Animal collections were kept by Charlemagne and other Euro¬ pean monarchs. Hernan Cortes described a zoo in Mexico (1519) so large that it required a staff of 300. Modern zookeeping started in 1752 with the founding of the Imperial Menagerie at Vienna’s Schonbrunn Palace. Open-range zoos were first established in the early 1930s, some so large that visitors drive through in cars, as on an African safari. There are now more than 1,000 animal collections open to the public throughout the world (e.g., in the U.S., the Bronx Zoo and San Diego Zoo).
zoology Branch of biology concerned with members of the animal king¬ dom and with animal life in general. The science originated in the works of Hippocrates, Aristotle, and Pliny. The contributions of individuals such as William Harvey (the circulation of blood), Carolus Linnaeus (system of nomenclature), Georges-Louis de Buffon (natural history), Georges Cuvier (comparative anatomy), and Claude Bernard (homeostasis) greatly advanced the field. The 1859 publication of Charles Darwin’s On the Origin of Species by Means of Natural Selection was a major turning point. Since that time, the study of genetics has become essential in zoological studies.
zooplankton \ l zo-9- , plaqk-t3n\ Small floating or weakly swimming animals that drift with water currents and, with phytoplankton, make up the planktonic food supply on which almost all oceanic organisms ulti¬ mately depend (see plankton). Included are many animals, from single- celled radiolarians to the eggs or larvae of herrings, crabs, and lobsters. Permanent plankton (holoplankton), such as protozoans and copepods, spend their lives as plankton. Temporary plankton (meroplankton), such as young starfish, clams, worms, and other bottom-dwelling animals, live and feed as plankton until they become adults.
Zorn, John (b. Sept. 2, 1953, New York, N.Y., U.S.) U.S. saxophonist and composer. His music incorporates influences from the most diverse elements of music and culture: free jazz, klezmer music, punk rock, cartoon music, film scores, and contemporary classical music. His “game pieces,” such as Cobra (1984), involve rules—understood by his musicians and cued by hand signals—that determine the flow of the music, placing emphasis on the process rather than the result of the performance.
Zoroaster Vzor-s-.was-torX or Zarathustra V.zar-o-'thiish-troN (b. c. 628, probably Rhages, Iran—d. c. 551 bce) Iranian religious reformer and prophet, founder of Zoroastrianism and Parsiism. He was a priest in his tribal religion, with which he eventually became disillusioned. Having received a vision, he began teaching that Ahura Mazda was the highest god and alone was worthy of worship, a concept that went against the polytheism of Iranian religion. He forbade the orgiastic rites that accom¬ panied animal sacrifice, common in his time, but preserved the ancient cult of fire worship. After converting a king called Vishtaspa to his teach¬ ings, Zoroaster remained at the royal court. He became the subject of leg¬ ends and a model for various occupations.
Zoroastrianism and Parsiism Ancient religion that originated in Iran based on the teachings of Zoroaster. Founded in the 6th century bce, it influenced the monotheistic religions Judaism, Christianity, and Islam. It rejects polytheism, accepting only one supreme God, Ahura Mazda. In early Zoroastrianism, the struggle between good and evil was seen as an eternal rivalry between Ahura Mazda’s twin sons, Spenta Mainyu (good) and Angra Mainyu (evil). Later Zoroastrian cosmology made the rivalry between Ahura Mazda himself (by then called Ormizd) and Angra Mainyu (Ahriman). This later cosmology identifies four periods of history; the last began with the birth of Zoroaster. Zoroastrian practice includes an initia¬ tion ceremony and various rituals of purification intended to ward off evil spirits. Fire worship, a carryover from an earlier religion, survives in the sacred fire that must be kept burning continually and be fed at least five times a day. The chief ceremony involves a sacrifice of haoma, a sacred liquor, accompanied by recitation of large parts of the Avesta, the primary
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Zorrilla ► Zurbaran I 2113
scripture. Zoroastrianism enjoyed status as an official religion at various times before the advent of Islam, but Zoroastrians were persecuted in the 8th-10th centuries, and some left Iran to settle in India. By the 19th cen¬ tury these Indian Zoroastrians, or Parsis, were noted for their wealth and education. The small group of Zoroastrians remaining in Iran are known as the Gabars.
Zorrilla \thor-'rel-ya\ (y Moral), Jose (b. Feb. 21, 1817, Valladolid, Spain—d. Jan. 23, 1893, Madrid) Spanish poet and dramatist. Zorrilla first gained notice in 1837 with his recitation of an elegy at the funeral of the satirist Mariano Jose de Larra. The major figure of the nationalist wing of the Spanish Romantic movement, he made his name with verse ley- endas (“legends”) about remote times and places, notably in Cantos del trovador (1841). His greatest success was Don Juan Tenorio (1844), the most popular play of 19th-century Spain. His works are considered quint- essentially Spanish in style and tone. In 1889 he was crowned the national poet.