nature/nurture controversy See behaviour genetics
Naucratis Vno-kro-tosX Ancient Greek settlement, in Egypt’s Nile River delta. It was founded in the 7th century bc and flourished as a centre of
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1336 I Nauru ► Navarino
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trade and cultural relations between Greece and Egypt. It declined after Alexander the Great’s conquest of Egypt and the founding of Alexandria in 332 bc. In 1884 archaeologist Funders Petrie discovered the site and helped excavate it.
Nauru \na-'u-rii\ officially Republic of Nauru Island country, south¬ eastern Micronesia, western South Pacific Ocean. Area: 8 sq mi (21 sq km). Population (2005): 10,200. Capitaclass="underline" Yaren (district). About two-thirds of the population are indigenous Nauruans. Languages: Nauruan, English. Religion: Christianity (mostly Protestant; also Roman Catholic). Currency: Australian dollar. Nauru is a coral island with a central plateau 100-200 ft (30-60 m) high. A thin strip of fertile land encircling the island is the major zone of human settlement. It lacks harbours; ships must anchor to buoys beyond a reef. Nauru once had the world’s largest concentration of phos¬ phate, and its economy was based on phosphate mining and processing; however, the deposits have been depleted, and the economy has been con¬ verting to fishing and other ventures. Nauru is a republic with one legisla¬ tive house; its head of state and government is the president. It was inhabited by Pacific Islanders when the first British explorers arrived in 1798 and named it Pleasant Island because of their friendly welcome. Annexed by Germany in 1888, it was occupied by Australia at the start of World War I, and in 1919 it was placed under a joint mandate of Britain, Australia, and New Zealand. During World War II it was occupied by the Japanese. Made a UN trust territory under Australian administration in 1947, Nauru gained complete independence in 1968 and became a full member of the Commonwealth and the UN in 1999.
nausea Discomfort in the pit of the stomach associated with disgust for food and a feeling that vomiting will follow, as it often does. Nausea results from irritation of nerve endings in the stomach or duodenum, which stimulate brain centres that control nausea and vomiting. Nausea can be a symptom of minor or serious disorders. Common causes include indi¬ gestion (from eating too fast or from stress around mealtime), food poi¬ soning, motion sickness, and pregnancy (morning sickness). Nausea may also arise from any cause of abnormal lack of appetite (e.g., shock, pain, influenza, badly fitting dentures, liver or kidney disease). Simple nausea often is relieved by vomiting.
nautilus \'no-t 3 l-3s\ Either of two genera of cephalopods. The pearly, or chambered, nautilus (genus Nauti¬ lus) lives in the outermost chamber of its smooth, coiled, usually 36-chambered shell, about 10 in. (25 cm) in diameter. A connecting tube adjusts the gases in the chambers, allowing the shell to act as a float.
Nautiluses search the ocean bottom for shrimp or other prey, which they capture with up to 94 small, sucker¬ less, contractile tentacles. The paper nautilus (genus Argonauta) feeds on plankton near the surface of tropical and subtropical seas. The female resembles an octopus but has a thin, unchambered, coiled shell, 12-16 in.
(30-40 cm) in diameter. The much smaller male has no shell.
Nautilus Any of at least three his¬ toric submarines. Robert Fulton built one of the earliest submersible craft in 1800 in France; his Nautilus had a collapsible mast and sail for sur¬ face propulsion and a hand-turned propeller for power. Andrew Campbell and James Ash of Britain built a Nautilus submarine driven by battery- powered electric motors in 1886. The name was also chosen for the world’s first nuclear-powered submarine, launched by the U.S. Navy in 1954. Capable of longer submersion than any previous submarine, it made a historic trip under the ice cap of the North Pole from Point Barrow, Alaska, to the Greenland Sea in 1958.
Navajo Vna-v3-,ho\ or Navaho North American Indian people living mostly in northwestern New Mexico, Arizona, and southeastern Utah, U.S. The Navajo speak an Athabaskan language related to that of the Apache. The Navajo and Apache migrated from Canada to the Southwest c. ad 900-1200, after which the Navajo came under the influence of the Pueblo Indians. Painted pottery and the famous Navajo rugs, as well as sandpainting, are products of this influence. The craft of silversmithing
probably came from Mexico in the mid-19th century. The traditional economy was based on farming and later herding of sheep, goats, and cattle. The basic social unit was the band. Religion focused on the emer¬ gence of the first people from worlds beneath the Earth’s surface. In 1863 the U.S. government ordered Col. Kit Carson to put an end to Navajo and Apache raiding; his offensives resulted in the incarceration of about 8,000 Navajo and the destruction of crops and herds. Today many Navajo live on or near the Navajo Reservation (24,000 sq mi [64,000 sq km] in New Mexico, Arizona, and Utah); thousands earn their living as transient work¬ ers. Their language has been tenaciously preserved; they used it to great effect during World War II by transmitting coded messages in Navajo. The Navajo are the most populous Native American group in the U.S., with about 270,000 individuals claiming sole Navajo descent in the 2000 U.S. census.
Navajo National Monument National monument, northern Ari¬ zona, U.S. Covering 360 acres (146 hectares), it comprises three historic cliff dwellings: Betatakin (Navajo: “Ledge House”), Keet Seel (“Broken Pottery”), and Inscription House, among the best-preserved and most elaborate cliff dwellings known. The largest, Keet Seel, was first discov¬ ered by whites in 1895; the three sites were made a national monument in 1909. The dwellings were the principal home of the Kayenta Anasazi c. 1250-1300. The 135 rooms of Betatakin are tucked into a cliffside alcove 452 ft (138 m) high and 370 ft (113 m) wide. Also situated in a cliff alcove are the 160 rooms and 6 kivas (ceremonial houses) of Keet Seel. Inscription House (closed to the public) has 74 rooms.
Navajo weaving Blankets and rugs made by the Navajo, considered among the best-made textiles produced by Native Americans of the U.S. By 1500 the Navajo were well established in what is now the southwest¬ ern U.S., where they began to practice weaving when they turned from a seminomadic life to agriculture. From the Hopi they learned how to make looms and weave fabrics on a large scale; but whereas the Hopi limited their designs to striped patterns, the Navajo introduced geometric shapes, diamonds, lozenges, and zigzags. Traditionally Navajo blankets were made of natural-coloured wool or wool in dark colours produced by dyes made from roots, herbs, and minerals. After the introduction of aniline dyes in the late 19th century, Navajo weavers began using brighter wools and a broader range of decorative motifs.
Naval Academy, U.S. See United States Naval Academy
Naval Limitation, International Conference on See Washing¬ ton Conference
naval warfare Military operations conducted on, under, or over the sea and waged against other seagoing vessels or targets on land or in the air. The earliest naval attacks were raids by the armed men of a tribe or town using fishing boats or merchant ships. The first warships were gal¬ leys, replaced in the 16th and 17th centuries by sail-driven warships equipped with cannons. The British victory over the Spanish Armada (1588) marked a major development: British galleons refused to allow the Spanish ships to get close enough for boarding and hand-to-hand combat and instead pounded them with guns of superior firing capability. Ships of the line and cruisers emerged in the 17th and 18th centuries. In the later 19th century, steam replaced sail propulsion, and ironclads offered greater protection against the increasing power of guns. The battleship, developed in these years, reigned until World War II, when the Pearl Har¬ bor attack proved that bombers launched from aircraft carriers could sink any and all surface ships. Since then, naval air power— missiles as well as carrier-based planes—has been the primary weapon of the world’s fleets. Submarines also play a major role in naval warfare.