© 2004 by The Society for Integrative and Comparative Biology
Can Optimal Resource Allocation Models Explain Why Ectotherms Grow Larger in Cold?1
owski2,1
ski1
ko1
1 Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
Basically all organisms can be classified as determinate growers if their growth stops or almost stops at maturation, or indeterminate growers if growth is still intense after maturation. Adult size for determinate growers is relatively well defined, whereas in indeterminate growers usually two measures are used: size at maturation and asymptotic size. The latter term is in fact not a direct measure but a parameter of a specific growth equation, most often Bertalanffy's growth curve. At a given food level, the growth rate in determinate growers depends under given food level on physiological constraints as well as on investments in repair and other mechanisms that improve future survival. The growth rate in indeterminate growers consists of two phases: juvenile and adult. The mechanisms determining the juvenile growth rate are similar to those in determinate growers, whereas allocation to reproduction (dependent on external mortality rate) seems to be the main factor limiting adult growth. Optimal resource allocation models can explain the temperature-size rule (stating that usually ectotherms grow slower in cold but attain larger size) if the exponents of functions describing the size-dependence of the resource acquisition and metabolic rates change with temperature or mortality increases with temperature. Emerging data support both assumptions. The results obtained with the aid of optimization models represent just a rule and not a law: it is possible to find the ranges of production parameters and mortality rates for which the temperature-size rule does not hold.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  M. Czarnoleski, J. Kozlowski, G. Dumiot, J.-C. Bonnet, J. Mallard, and M. Dupont-Nivet Scaling of metabolism in Helix aspersa snails: changes through ontogeny and response to selection for increased size J. Exp. Biol., February 1, 2008; 211(3): 391 - 400. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. L Chown and P. Convey Spatial and temporal variability across life's hierarchies in the terrestrial Antarctic Phil Trans R Soc B, December 29, 2007; 362(1488): 2307 - 2331. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Hunt and K. Roy Climate change, body size evolution, and Cope's Rule in deep-sea ostracodes PNAS, January 31, 2006; 103(5): 1347 - 1352. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. W. Sears and M. J. Angilletta Jr. Body Size Clines in Sceloporus Lizards: Proximate Mechanisms and Demographic Constraints Integr. Comp. Biol., December 1, 2004; 44(6): 433 - 442. [Abstract] [Full Text] [PDF]
|
|