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Eve, in genetics

(Encyclopedia)Eve, in genetics, popular term for a theoretical female ancestor of all living people, also known as Mitochondrial Eve. In 1987 biochemist Allan C. Wilson proposed that all living human beings had inh...

family, in taxonomy

(Encyclopedia)family, in taxonomy: see classification. ...

family, in sociology

(Encyclopedia)family, a basic unit of social structure, the exact definition of which can vary greatly from time to time and from culture to culture. How a society defines family as a primary group, and the functio...

farming, in agriculture

(Encyclopedia)farming, in agriculture: see agriculture. ...

farming, in taxation

(Encyclopedia)farming, in the history of taxation, collection of taxes through private contractors. Usually, the tax farmer paid a lump sum to the public treasury; the difference between that sum and the sum actual...

fatigue, in engineering

(Encyclopedia)fatigue, in engineering, microscopic cracking of materials, especially metals, after repeated applications of stress. Fissures may be formed within pieces of metal during their manufacture when, while...

fatigue, in physiology

(Encyclopedia)fatigue, in physiology, inability to perform reasonable and necessary physical or mental activity. Muscle fatigue, for example, results when the contractile properties of muscle are reduced, and conti...

Epimetheus, in astronomy

(Encyclopedia)Epimetheus, in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn XI (or S11), Epimetheus is an irregularly shaped (nonspherical) body measuring about 89 mi (144...

Eris, in astronomy

(Encyclopedia)Eris, in astronomy, the largest known dwarf planet. Eris, whose highly eccentric elliptical orbit ranges from 38 AU to 97 AU and is inclined more than 44°, is the largest known object of the Kuiper b...

Eros, in astronomy

(Encyclopedia)Eros, in astronomy: see asteroid. ...