bird Any of the warm-blooded, beaked vertebrates of the class Aves, including more than 9,600 living species. A covering of feathers distin-
co verts
hind toe (hallux)
forehead__
upper
mandible
chin lores throat breast — side abdomen flank tarsus
auricular (ear patch) nape side of neck
bend of wing-
back-
scapulars — wing coverts
secondaries
tail feathers (rectrices)
Principal features of a songbird.
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guishes birds from all other animals. Birds have a four-chambered heart (like mammals), forelimbs modified into wings, and keen vision, and their eggs have calcium-rich eggshells. Their sense of smell is not highly devel¬ oped. Birds are found almost worldwide in diverse habitats on both land and water. Dietary preferences and nest structure vary widely. Almost all species incubate their eggs. Flying birds have evolved skeletons in which part of the bone is replaced by air spaces, an adaptation for reducing weight. The crop, an enlarged part of the esophagus used for temporary food storage, enables birds to feed while in flight. Humans use wild and domesticated birds and their eggs for food, hunt wild birds for sport, and use feathers for decoration and insulation. More than 1,000 extinct spe¬ cies of bird have been identified from fossil remains; the earliest fossil bird known is Archaeopteryx.
Bird, Larry (Joe) (b. Dec. 7, 1956, West Baden, Ind., U.S.) U.S. bas¬ ketball player. Bird spent most of his collegiate career at Indiana State University, before being drafted by the Boston Celtics of the National Basketball Association (NBA). Playing forward and standing 6 ft 9 in. (2.06 m) tall, he was a great shooter and ball handler and one of the most formidable playmakers in the game. He helped lead Boston to NBA cham¬ pionships in 1981, 1984, and 1986 and was named the NBA’s most valu¬ able player for three consecutive years (1984-86). He retired in 1992 and was head coach of the Indiana Pacers for the 1997-98 season.
bird flu or avian influenza viral respiratory disease, mainly of birds including poultry and waterbirds but also transmissible to humans. Symp¬ toms in humans include fever, sore throat, cough, headache, and muscle aches. Severe infections can result in life-threatening complications such as pneumonia and acute respiratory illness. The first known human cases occurred in Hong Kong in 1997, resulting in six deaths. Deadly outbreaks among poultry in several countries in eastern and central Asia between 2003 and mid-2005 were accompanied by more than 100 human cases, about half of them fatal. The causative agents are virus subtypes related to the human influenza type A viruses, the most virulent and contagious being the H5N1 subtype. A specific protective vaccine for this virus remains to be developed. Studies suggest that some antiviral drugs that work against human influenza may be effective in treating bird flu in humans.
bird-of-paradise Any of about 40 species (family Paradisaeidae) of small to medium-size forest birds that are rivaled by only a few pheas¬ ants and hummingbirds in colour and in the bizarre shape of the males’ plumage. Courting males perform mating rituals for hours on a perch or in a cleared space on the forest floor. Birds-of-paradise are found in the highlands of New Guinea and on nearby islands; some species are also found in Australia. Among the most notable species are the plumebirds, which are 12-18 in. (30^46 cm) long and have central tail feathers elon¬ gated as wires or twisted ribbons.
bird-of-paradise or crane flower Ornamental plant (Strelitzia reginae ) of the family Strelitziaceae. All five species of the genus Strel¬ itzia are native to southern Africa. The large, showy Strelitzia flower has two erect, pointed petals and five stamens. One main bract, shaped like a boat, is green with red borders. It holds many long-stemmed orange and bright blue flowers, each resembling the crest and beak of a crane, giv¬ ing the plant its common names.
bird of prey Any member of the order Falconiformes (eagles, falcons, hawks, and vultures) or Strigiformes (owls). Falconiforms are also called raptors. They are active during the day, whereas owls are nocturnal. Con¬ dors and eagles are among the largest and strongest of flying birds. All birds of prey have a hook-tipped beak and sharp curved claws called tal¬ ons. (Nonpredatory vultures have less-developed talons.) Despite the similarities between owls and raptors, many authorities believe they are not closely related but developed similar features because of their simi¬ lar predatory lives.
bird stone Abstract stone carving by the prehistoric cultures of North America. They resemble birds and are about 6 in. (15 cm) long. Many were carved from black, brown, or dark green slate and polished with sand or other abrasive materials. All feature a pair of conical holes run¬ ning diagonally through the base. They may have been used as weights or handles on a short rod (known as an atlatl) used to hurl spears or arrows.
bird-watching or birding Observation or identification of wild birds in their natural habitat. Basic equipment includes binoculars, a field guide to aid identification, and a notebook for recording time and place of sight-
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bird's-foot trefoil ► Biscay I 223
ings. The lists of bird observations compiled by members of local bird¬ watching societies are often useful to scientists in determining dispersal, habitat, and migration patterns of the various species. Bird-watching is primarily a 20th-century phenomenon; before 1900 most students of birds had to shoot them in order to identify them. Its popularity grew through the publication of journals and books, in particular the field guides (begin¬ ning in 1934) of Roger Tory Peterson.
bird's-foot trefoil Perennial, spreading, herbaceous legume {Lotus cor- niculatus ) native to Europe and Asia but introduced to other regions. The stem grows to about 2 ft (60 cm) long. Its leaves consist of three oval leaflets, broadest near the tip. The yellow flowers (sometimes tinged with red) grow in clusters of 5 to 10. Often used as forage for cattle, it is occa¬ sionally a troublesome weed.
Birdseye, Clarence (b. Dec. 9, 1886, New York, N.Y., U.S.—d. Oct. 7, 1956, New York) U.S. businessman and inventor. He developed a highly efficient process for freezing foods in small packages suitable for retailing. He achieved rapid freezing by placing packaged food, includ¬ ing fish, fruits, and vegetables, between two refrigerated metal plates. Though his were not the first frozen foods, his process largely preserved the original taste of the food. In 1929 his company was bought by Pos- tum, Inc., which later became General Foods Corp. Birdseye served as a corporate executive until 1938.
birdsong Certain vocalizations of birds, characteristic of males during the breeding season, for the attraction of a mate and for territorial defense. Birdsong also reinforces pair bonds, and some species have a flight song. Birdsongs are usually more complex and longer than birdcalls, which are used for communication within a species. Birdsong may be hereditary or learned; a newly hatched male chaffinch, for example, can sing a “sub¬ song” but must learn to sing the true song by listening to and imitating adult males.
birefringence See double refraction
Biringuccio Nbe-req-'giit-choV Vannoccio (b. Oct. 20, 1480, Siena—d. August 1537, Rome) Italian metallurgist and armaments maker. He is chiefly known for the first clear, comprehensive work on metallurgy, De la pirotechnia (published posthumously in 1540). His book, which contrasts strikingly with the obscure alchemical writings of the time, is replete with lavish woodcuts illustrating equipment and processes and includes clear, practical instructions for mining, smelting, and metalwork¬ ing. It became a standard reference and remains a valuable resource on 15th- and 16th-century technology.