Several essentially different death curves can be observed for different plant population.
1. In the case of seasonal, annual, and monocarpic species, senescence can be dramatic. Until a certain stage, plants develop, elongate and produce grain/fruit and menifest a very low incidence of mortality. However, after the sensing of certain death signal, all individual cells die off with military parade precision. Curve E is typical of such behavior and is designated as a square wave.
1. In the case of seasonal, annual, and monocarpic species, senescence can be dramatic. Until a certain stage, plants develop, elongate and produce grain/fruit and menifest a very low incidence of mortality. However, after the sensing of certain death signal, all individual cells die off with military parade precision. Curve E is typical of such behavior and is designated as a square wave.
Curve C is typical of human and domestic animal mortility. The more progressive the society the smaller the peak indicating infant mortality. After a period of relative stability, maximal mortality is observed in the latter period of life span.
Under certain circumstances of regulated diet and hygiene, the sygmoidal curve C, may be deflected to the square wave trend i.e. curve D, which has a definite advantage.
Curve A,B are believed to be typical to the perennial and polycarpic trees and shrubs. Also called as "an ecological mortility curve" typical of wild animals where very few individuals live to die of natural causes and not prey to younger or stronger animals, disease or natural disasters.
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