Literaturdatenbank |
Ben-Ezra, E. (2006). A test of the thermal coadaptation hypothesis in the common map turtle (graptemys geographica). Unpublished thesis , University of Ottawa.
Added by: Sarina Wunderlich (25 Jan 2011 10:31:50 UTC) |
Resource type: Thesis/Dissertation BibTeX citation key: BenEzra2006 View all bibliographic details |
Categories: General Keywords: Emydidae, Graptemys, Graptemys geographica, Habitat = habitat, Nordamerika = North America, Schildkröten = turtles + tortoises Creators: Ben-Ezra Publisher: University of Ottawa |
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Abstract |
According to the thermal coadaptation hypothesis, the preferred body temperature (Tset) of ectotherms should match their optimal temperature (To) for performance. The first objective of this study was to test this prediction with male common map turtles (Graptemys geographica) by determining Tset and To for swimming speed and righting time. The second objective was to compare Tset measured by two different methods: a dry thermal gradient and an aquatic basking arena. The third objective was to determine if there are any ontogenetic changes in performance by comparing hatchling and adult male turtles. Given that map turtles are highly aquatic, we contend that the Tset determined in the basking arena (22.5oC – 31.8oC) better represents To. In the dry gradient, Tset (23.5oC – 25.9oC) was likely affected by the unnatural environment in which moisture may have been a limiting factor. The optimal temperatures for swimming (28.6oC) and righting (31.6oC) were within the Tset range determined from the basking arena but not from the dry gradient. Performance curves were shifted to colder temperatures for hatchling turtles compared to adults, though the difference was non-significant for righting. Overall, our study has provided evidence in support of the thermal coadaptation hypothesis for two locomotory performances and demonstrated a new, more effective method for determining preferred body temperatures of turtles.
Added by: Sarina Wunderlich |