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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1999-6-29
|
| pubmed:abstractText |
I recorded body temperature and behaviour of eight Crocodylus johnstoni in the wild over a 2-yr period in order to quantify the effect of posturing on body temperature and to provide a mechanistic explanation of how behaviour affects body temperature. Behaviour was categorised according to the proportion of a crocodile's surface area exposed from the water (0% exposed [=diving] to 100% exposed [=basking]). Crocodiles did not simply shuttle between the extremes of 100% exposed and diving but showed an array of intermediate postures. Rates of body temperature change were negative for exposures less than 40% and positive for 60%-100% exposed. This was due to the difference between operative temperature and body temperature, which was negative during diving but increased with the percentage of exposure, up to 25 degrees-30 degrees C during basking. For any particular posture, the rate of body temperature change decreased with increasing mass. Thermal time constants were shortest during diving and longest during basking. A heat-transfer equation predicted the rate of body temperature change well, except that it underestimated the rate of body temperature change during 80% and 100% exposed. Exposing only a small part of their body when in water (20%) slowed heat loss considerably, allowing crocodiles to spend more time in the water while maintaining body temperature within their preferred body temperature range.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:status |
MEDLINE
|
| pubmed:issn |
1522-2152
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
72
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
57-63
|
| pubmed:dateRevised |
2003-11-14
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| pubmed:meshHeading |
pubmed-meshheading:9882603-Alligators and Crocodiles,
pubmed-meshheading:9882603-Animals,
pubmed-meshheading:9882603-Body Temperature,
pubmed-meshheading:9882603-Body Temperature Regulation,
pubmed-meshheading:9882603-Female,
pubmed-meshheading:9882603-Male,
pubmed-meshheading:9882603-Motor Activity,
pubmed-meshheading:9882603-Posture
|
| pubmed:articleTitle |
Behavioural postures and the rate of body temperature change in wild freshwater crocodiles, Crocodylus johnstoni.
|
| pubmed:affiliation |
Department of Zoology, University of Queensland, Brisbane, Australia. fseebacher@zoology.uq.edu.au
|
| pubmed:publicationType |
Journal Article
|