Article

Dynamic heterogeneity and life histories

Department of Biology, Stanford University, Stanford, California
Annals of the New York Academy of Sciences (impact factor: 3.15). 07/2010; 1204(1):65 - 72. DOI:10.1111/j.1749-6632.2010.05519.x pp.65 - 72

ABSTRACT Biodemography is increasingly focused on the large and persistent differences between individuals within populations in fitness components (age at death, reproductive success) and fitness-related components (health, biomarkers) in humans and other species. To study such variation we propose the use of dynamic models of observable phenotypes of individuals. Phenotypic change in turn determines variation among individuals in their fitness components over the life course. We refer to this dynamic accumulation of fitness differences as dynamic heterogeneity and illustrate it for an animal population in which longitudinal data are studied using multistate capture-mark-recapture models. Although our approach can be applied to any characteristic, for our empirical example we use reproduction as the phenotypic character to define stages. We indicate how our stage-structured model describes the nature of the variation among individual characteristics that is generated by dynamic heterogeneity. We conclude by discussing our ongoing and planned work on animals and humans. We also discuss the connections between our work and recent work on human mortality, disability and health, and life course theory.

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Keywords

animal population
 
Biodemography
 
define stages
 
dynamic heterogeneity
 
empirical example
 
fitness components
 
fitness differences
 
fitness-related components
 
humans
 
individual characteristics
 
life course
 
life course theory
 
longitudinal data
 
multistate capture-mark-recapture models
 
persistent differences
 
Phenotypic change
 
phenotypic character
 
recent work
 
reproductive success
 
stage-structured model