Evolution
Paul D. MacLean, as part of his triune brain theory, hypothesized that the limbic system is older than other parts of the brain, and that it developed to manage fight or flight circuitry which is an evolutionary necessity for reptiles as well as humans. However, recent studies of the limbic system of tetrapods have challenged some long-held tenets of forebrain evolution. The common ancestors of reptiles and mammals had a well-developed limbic system in which the basic subdivisions and connections of the amygdalar nuclei were established.
Read more about this topic: Limbic System
Famous quotes containing the word evolution:
“The evolution of sense is, in a sense, the evolution of nonsense.”
—Vladimir Nabokov (1899–1977)
“The more specific idea of evolution now reached is—a change from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity, accompanying the dissipation of motion and integration of matter.”
—Herbert Spencer (1820–1903)
“By contrast with history, evolution is an unconscious process. Another, and perhaps a better way of putting it would be to say that evolution is a natural process, history a human one.... Insofar as we treat man as a part of nature—for instance in a biological survey of evolution—we are precisely not treating him as a historical being. As a historically developing being, he is set over against nature, both as a knower and as a doer.”
—Owen Barfield (b. 1898)