theory of generic cycles

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generic cycles, theory of A theory which envisages a life cycle for a species or genus that resembles that of an individual. The first stage is characterized by vigorous spread; the second by maximum phyletic activity giving rise to new forms; the third marks a phase of decline in area, owing to competition within the offspring species; and the fourth and final stage sees the extinction of the species. Although in many ways a useful analogy, there is no evidence that species become senile and die out spontaneously.

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generic cycles, theory of A theory that envisages a life cycle for a species or genus that resembles that of an individual. The first stage is characterized by vigorous spread; the second by maximum phyletic activity giving rise to new forms; the third marks a phase of decline in area owing to competition within the offspring species; and the fourth and final stage sees the extinction of the species. Although in many ways a useful analogy, there is no evidence that species become senile and die out spontaneously.

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generic cycles, theory of A theory that envisages a life cycle for a species or genus analogous to that of an individual. The first stage is characterized by vigorous spread; the second by maximum phyletic activity giving rise to new forms; the third marks a phase of decline in area due to competition within the offspring species; and the fourth and final stage sees the extinction of the species. Although in many ways a useful analogy, there is no evidence that species become senile and die out spontaneously.

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theory of generic cycles See generic cycles, theory of.

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theory of generic cycles See GENERIC CYCLES, THEORY OF.

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theory of generic cycles See GENERIC CYCLES, THEORY OF.