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fisheries

(Encyclopedia)fisheries. From earliest times and in practically all countries, fisheries have been of industrial and commercial importance. In the large N Atlantic fishing grounds off Newfoundland and Labrador, for...

pollution

(Encyclopedia)pollution, contamination of the environment as a result of human activities. The term pollution refers primarily to the fouling of air, water, and land by wastes (see air pollution; water pollution; s...

illiteracy

(Encyclopedia)illiteracy, inability to meet a certain minimum criterion of reading and writing skill. Throughout most of history most people have been illiterate. In feudal society, for example, the ability to re...

Rhodes, Cecil John

(Encyclopedia)Rhodes, Cecil John sĕsˈĭl, rōdz [key], 1853–1902, British imperialist and business magnate. A trip in 1875 through the rich territories of Transvaal and Bechuanaland apparently helped to insp...

coral reefs

(Encyclopedia)coral reefs, limestone formations produced by living organisms, found in shallow, tropical marine waters. In most reefs, the predominant organisms are stony corals, colonial cnidarians that secrete an...

frog

(Encyclopedia)frog, common name for an amphibian of the order Anura. Frogs are found all over the world, except in Antarctica. They require moisture and usually live in quiet freshwater or in the woods. Some frogs ...

amphetamine

(Encyclopedia)amphetamine ămfĕtˈəmēn [key], any one of a group of drugs that are powerful central nervous system stimulants. Amphetamines have stimulating effects opposite to the effects of depressants such as...

insecticides

(Encyclopedia)insecticides, chemical, biological, or other agents used to destroy insect pests; the term commonly refers to chemical agents only. The liabilities of chemical insecticides have encouraged interest ...

in vitro fertilization

(Encyclopedia)in vitro fertilization vēˈtrō, vĭˈtrō [key] (IVF), technique for conception of a human embryo outside the mother's body. Several ova, or eggs, are removed from the mother's body and placed in sp...

endangered species

(Encyclopedia)endangered species, any plant or animal species whose ability to survive and reproduce has been jeopardized by human activities. In 1999 the U.S. government, in accordance with the U.S. Endangered Spe...