Animal Physiological Ecology
Metabolic theory, life history and the distribution of a terrestrial ectotherm
Article first published online: 13 OCT 2011
© 2011 The Author. Functional Ecology © 2011 British Ecological Society
Volume 26, Issue 1, pages 167–179, February 2012
How to Cite
Kearney, M. (2012), Metabolic theory, life history and the distribution of a terrestrial ectotherm. Functional Ecology, 26: 167–179. doi: 10.1111/j.1365-2435.2011.01917.x
- Issue published online: 18 JAN 2012
- Article first published online: 13 OCT 2011
- Received 9 March 2011; accepted 23 August 2011 Handling Editor: Gretchen Hofmann
- biophysical ecology;
- dynamic energy budget theory;
- geographic range limits;
- niche modelling;
- Sceloporus undulatus;
- species distribution modelling;
1. Life histories, population dynamics and geographic range limits are fundamentally constrained by the way organisms acquire and allocate energy and matter. Metabolic theories provide general, parameter-sparse frameworks for understanding these constraints. However, they require the accurate estimation of body temperature which can be especially challenging in terrestrial environments.
2. Here, I integrate a metabolic theory (Dynamic Energy Budget theory, DEB) with a biophysical model for inferring field body temperatures and activity periods of terrestrial ectotherms and apply it to study life-history variation and geographic range limits in a widespread North American lizard, Sceloporus undulatus.
3. The model successfully predicted trait co-variation (size at maturity, maximum size, reproductive output and length-mass allometry) through changes in a single parameter. It also predicted seasonal and geographic variation in field growth rates, age at first reproduction, reproductive output and geographic range limits (via rmax estimates), all as a function of spatial climatic data. Although variation in age at maturity was mostly explained by climate, variation in annual reproduction was largely a product of local body size.
4. Dynamic Energy Budget metabolic theory is concluded to be a powerful and general means to mechanistically integrate the dynamics of growth and reproduction into niche models of ectotherms.