Growing more positive with age: The relationship between reproduction and survival in aging flies.

Growing more positive with age: The relationship between reproduction and survival in aging flies. Exp Gerontol. 2017 Jan 22;: Authors: van den Heuvel J, Zandveld J, Brakefield PM, Kirkwood TB, Shanley DP, Zwaan BJ Abstract Populations of laboratory animals that are selected for increased lifespan often show negative correlated responses in early fecundity. However, late fecundity and/or total lifetime fecundity can be higher in the populations selected for increased lifespan. This has been interpreted by some as being at odds with the disposable soma theory, which predicts decreased lifespan to increase total reproductive output. Alternatively, the Y-model explores the effects of variation in resource allocation and acquisition on life histories. In this model, a negative relationship between lifespan and reproduction can be viewed as variation in allocation, whereas a positive relationship is the result of variation in acquisition. However, a frequently neglected complication of the Y-model is that older individuals often show a decline in resource acquisition. Therefore, differential allocation to maintenance and survival might affect this decline in late-life acquisition which will affect resource availability across the whole lifespan. In this paper we show that a model which incorporates the ideas of the Y-model, the disposable soma theory, and an age-related decrease in resource acquisition, i.e. feeding senescence, can explai...
Source: Experimental Gerontology - Category: Geriatrics Authors: Tags: Exp Gerontol Source Type: research