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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 ...

marine biology

(Encyclopedia)marine biology, study of ocean plants and animals and their ecological relationships. Marine organisms may be classified (according to their mode of life) as nektonic, planktonic, or benthic. Nektonic...

reclamation of land

(Encyclopedia)reclamation of land, practice of converting land deemed unproductive into arable land by such methods as irrigation, drainage, flood control, altering the texture and mineral and organic content of so...

fox, in zoology

(Encyclopedia)fox, carnivorous mammal of the dog family, found throughout most of the Northern Hemisphere. It has a pointed face, short legs, long, thick fur, and a tail about one half to two thirds as long as the ...

Arizona

(Encyclopedia)CE5 Arizona ârˌəzōˈnə [key], state in the SW United States. It is bordered by Utah (N), New Mexico (E), Mexico (S), and, largely across the Colorado River, Nevada and California (W); it touch...

Twain, Mark

(Encyclopedia)Twain, Mark, pseud. of Samuel Langhorne Clemens, 1835–1910, American author, b. Florida, Mo. As humorist, narrator, and social observer, Twain is unsurpassed in American literature. His novel The Ad...

Colorado, state, United States

(Encyclopedia)CE5 Colorado kŏlərădˈə, –rădˈō, –räˈdō [key], state, W central United States, one of the Rocky Mt. states. It is bordered by Wyoming (N), Nebraska (N, E), Kansas (E), Oklahoma and Ne...

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...

ocean

(Encyclopedia)ocean, interconnected mass of saltwater covering 70.78% of the surface of the earth, often called the world ocean. It is subdivided into four (or five) major units that are separated from each other i...

American literature

(Encyclopedia)American literature, literature in English produced in what is now the United States of America. The years immediately after World War I brought a highly vocal rebellion against established socia...

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