Mortality plateaus and directionality theory
نویسندگان
چکیده
منابع مشابه
Mortality plateaus and directionality theory.
Recent large scale studies of senescence in animals and humans have revealed mortality rates that levelled off at advanced ages. These empirical findings are now known to be inconsistent with evolutionary theories of senescence based on the Malthusian parameter as a measure of fitness. This article analyses the incidence of mortality plateaus in terms of directionality theory, a new class of mo...
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Most demographic data indicate a roughly exponential increase in adult mortality with age, a phenomenon that has been explained in terms of a decline in the force of natural selection acting on age-specific mortality. Scattered demographic findings suggest the existence of a late-life mortality plateau in both humans and dipteran insects, seemingly at odds with both prior data and evolutionary ...
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We show that deceleration in hazard functions (mortality curves) and the resulting mortality plateaus are an intrinsic property of time-to-event traits that are affected by many underlying genetic and environmental factors. We argue that just demonstrating that a mortality curve decelerates with age and reaches a plateau provides little information about the underlying biology associated with l...
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ژورنال
عنوان ژورنال: Proceedings of the Royal Society of London. Series B: Biological Sciences
سال: 2001
ISSN: 0962-8452,1471-2954
DOI: 10.1098/rspb.2001.1739