Although Bergmann's rule was originally proposed for homeotherms, Bergmannian (and converse Bergmannian) clines occur in invertebrate and vertebrate ectotherms
(Ray 1960; Masaki 1967, 1978; Honek 1993; Atkinson 1994; Mousseau 1997; Arnett & Gotelli 1999; Brisola Marcondes et al.
Future investigation will include the testing of the eggs from the brood stock, clinically healthy animals, rookery birds, and free-ranging alligators to explore the epidemiology of this virus in ectotherms
5) were consistent with a number of biologically plausible food webs: vertebrate ectotherms
as predator and consumer (body size ratio of 12:1), invertebrate ectotherms
as predator and consumer (12:1), and a vertebrate ectotherm
predator and an invertebrate ectotherm
Temperature and organism size: a biological law for ectotherms
Similar intraclade mixing patterns have been observed in other terrestrial ectotherms
(Brehm & Fiedler 2004, Dillon et al.
It predicts a negative genetic correlation between maximum rate of performance and performance breadth within populations of ectotherms
(Huey and Hertz 1984; Huey and Kingsolver 1989; Gilchrist 1996).
For example, because of seasonal differences in metabolic responses, we feel that ectotherms
may depart significantly enough from deterministic model assumptions that predictive ability may be compromised.
Although most ectotherms
have only limited ability to thermoregulate via physiological adjustment, many use behavioral adjustments to regulate body temperatures at remarkably narrow species-specific levels (Huey 1991, Madeira et al.
Hence, oxygen could be the key resource limiting growth in aquatic ectotherms
The importance of morphological and behavioral traits for managing body temperature has been demonstrated in many terrestrial ectotherms
such as insects, reptiles, and gastropods (Schmidt-Nielsen et al.
Lizards are ectotherms
, regulating their body temperature by exchanging heat with their surroundings.
, reptiles and amphibians make efficient use of energy (Pough, 1980) and, thus, many ecosystems are capable of supporting extraordinarily high densities of herpetofauna compared to endothermic vertebrates (Burton and Likens, 1975; Fitch, 1975; Godley, 1980; Petranka and Murray, 2001).
Thus, during periods of highest ambient temperature, seeking refuge under plant debris may not allow ectotherms
to adjust body temperatures within the preferred range (Punzo 2000b).
The observation that food quality and quantity can cause ectotherms
to mature earlier at a larger size has received much recent attention (Berrigan and Charnov 1994, Ernsting 1995, Perrin 1995, Atkinson and Sibly 1996).
Van Voorhies (1996) has suggested that, in general, ectotherms
increase in size when they develop at lower temperatures through an inevitable increase in cell size and that the response is not adaptive.