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Oligocene epoch

(Encyclopedia)Oligocene epoch ŏlˈəgōsēnˌ [key], third epoch of the Tertiary period in the Cenozoic era of geologic time, lasting from 38 to 24 million years ago. More of North America was dry land during the ...

competition, in biology

(Encyclopedia)competition, in biology, relationship between members of the same or different species in which individuals are adversely affected by those having the same living requirements, such as food or space. ...

cockroach

(Encyclopedia)cockroach or roach, name applied to some 4,600 species of flat-bodied, oval insects in the order Blattodea. Cockroaches have long antennae, long legs adapted to running, and a flat extension of the up...

extinction

(Encyclopedia)extinction, in biology, disappearance of species of living organisms. Extinction usually occurs as a result of changed conditions to which the species is not suited. If no member of the affected speci...

Paine, Robert Treat, 3d

(Encyclopedia)Paine, Robert Treat, 3d, 1933–2016, American ecologist, b. Cambridge, Mass., Ph.D. Univ. of Michigan, 1961. He was on the faculty of the Univ. of Washington from 1962 to 1998. Paine's major contribu...

Australopithecus

(Encyclopedia)Australopithecus ôstrāˌlōpĭthˈəkəs, –pəthēˈkəs [key], an extinct hominin genus found in Africa between about 4 and 1 million years ago. At least seven species of australopithecines are n...

adaptive radiation

(Encyclopedia)CE5 Adaptive radiation in Hawaiian honey-creepers adaptive radiation, in biology, the evolution of an ancestral species, which was adapted to a particular way of life, into many diverse species, e...

biogenetic law

(Encyclopedia)biogenetic law, in biology, a law stating that the earlier stages of embryos of species advanced in the evolutionary process, such as humans, resemble the embryos of ancestral species, such as fish. T...

Priapulida

(Encyclopedia)Priapulida, phylum consisting of 17 species of predatory, unsegmented marine worms that live in the sand and mud at the sea bottom. The largest are 4 to 6 in. (10–17 cm) long, but the majority of sp...

Darwin's finches

(Encyclopedia)Darwin's finches or Galapagos finches gəläˈpəgōsˌ [key], species of small perching birds, constituting the subfamily Geospizinae of the tanager family. Not related to the true finches, this grou...