Parameter Tree:
EARTH SCIENCE > BIOSPHERE > ECOLOGICAL DYNAMICS > SPECIES/POPULATION INTERACTIONS > EXOTIC SPECIES

Definition:
Exotic species are those that are introduced to a geographical area where
they are not native. 


Reference:
Nebel, Bernard J.and Richard T. Wright. 1998. Environmental Science-the Way the
World Works. Prentice-Hall, Inc. Upper Saddle River, New Jersey.