Open AccessDiet restriction and life history trade‐offs in short‐ and long‐lived species of Daphnia
Author(s) -
Latta Leigh Clark,
Frederick Shan,
Pfrender Michael Eugene
Publication year - 2011
Publication title -
journal of experimental zoology part a: ecological genetics and physiology
Language(s) - English
Resource type - Journals
eISSN - 1932-5231
pISSN - 1932-5223
DOI - 10.1002/jez.710
Subject(s) - biology , daphnia pulex , longevity , fecundity , reproduction , daphnia , life history theory , ecology , trade off , starvation , organism , zoology , life history , demography , genetics , endocrinology , population , crustacean , sociology
The life‐extending effects of diet restriction are well documented. One evolutionary model that accounts for this widespread conservation is the resource allocation model, where the selected individuals are those that can delay reproduction during periods of resource limitation. In this study, we use closely related species of a model organism, Daphnia , with widely divergent lifespans to address the relationship between diet restriction and longevity and assess whether the relationships are owing to trade‐offs between reproductive and somatic investment. Specifically, we conducted a common garden experiment and constructed reaction norms for lifespan, fecundity, and body size as a function of food concentration. Our study provides evidence that the short‐lived species in our study, D. pulex , shows the classically observed relationship of enhanced lifespan in response to reduced diet intake, but does not divert resources to somatic maintenance at the expense of reproduction during chronic diet restriction. In contrast, we find no evidence that the long‐lived species in our study, D. pulicaria , gains any life‐extending effects through diet restriction. Combined, our results provide evidence that the resource allocation model is not sufficient to explain the evolution of diet‐mediated lifespan plasticity. J. Exp. Zool. 315:610–617, 2011 . © 2011 Wiley Periodicals, Inc.