Temperature selection by juvenile tuatara ( Sphenodon punctatus ) is not influenced by temperatures experienced as embryos

2017 ◽  
Vol 69 ◽  
pp. 261-266 ◽  
Author(s):  
Nicola J. Nelson ◽  
Susan N. Keall ◽  
Kelly M. Hare
1971 ◽  
Vol 28 (11) ◽  
pp. 1801-1804 ◽  
Author(s):  
R. W. McCauley ◽  
W. L. Pond

Preferred temperatures of underyearling rainbow trout (Salmo gairdneri) were determined in both vertical and horizontal temperature gradients. No statistically significant difference was found between the preferred temperatures by the two different methods. This suggests that the nature of the gradient plays a lesser role than generally believed in laboratory investigations of temperature preference.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
J. Robert Macey ◽  
Stephan Pabinger ◽  
Charles G. Barbieri ◽  
Ella S. Buring ◽  
Vanessa L. Gonzalez ◽  
...  

AbstractAnimal mitochondrial genomic polymorphism occurs as low-level mitochondrial heteroplasmy and deeply divergent co-existing molecules. The latter is rare, known only in bivalvian mollusks. Here we show two deeply divergent co-existing mt-genomes in a vertebrate through genomic sequencing of the Tuatara (Sphenodon punctatus), the sole-representative of an ancient reptilian Order. The two molecules, revealed using a combination of short-read and long-read sequencing technologies, differ by 10.4% nucleotide divergence. A single long-read covers an entire mt-molecule for both strands. Phylogenetic analyses suggest a 7–8 million-year divergence between genomes. Contrary to earlier reports, all 37 genes typical of animal mitochondria, with drastic gene rearrangements, are confirmed for both mt-genomes. Also unique to vertebrates, concerted evolution drives three near-identical putative Control Region non-coding blocks. Evidence of positive selection at sites linked to metabolically important transmembrane regions of encoded proteins suggests these two mt-genomes may confer an adaptive advantage for an unusually cold-tolerant reptile.


2021 ◽  
Author(s):  
Joe Shine ◽  
Thomas Heinold ◽  
Don Lawrence

Abstract The risk of improper temperature selection for the design and testing of cement slurries can be detrimental to well construction operations and could affect a well's integrity. The methods for temperature selection in API 10B-2 do not consistently reflect the representative bottomhole conditions for high temperature applications. More so, consider 10B-2 guidance valuable for proving benchmarks in the high temperature domain. Therefore, numerical temperature simulators help manage the risk by predicting the anticipated bottomhole cementing temperatures. Currently several temperature simulators are in use to predict, with better accuracy, cementing bottomhole temperatures. The manuscript investigates the strange differences in predictions between the simulators for a range of high temperature applications. The results of the work efforts should help end users understand the outputs allowing better judgement when selecting representative bottomhole cementing temperatures for a given application.


1989 ◽  
Vol 256 (5) ◽  
pp. R1160-R1163 ◽  
Author(s):  
B. T. Firth ◽  
M. B. Thompson ◽  
D. J. Kennaway ◽  
I. Belan

Daily rhythms in plasma melatonin levels were compared in two ecologically diverse reptilian species under natural environmental conditions in autumn. The nocturnal, cold temperature-adapted tuatara (Sphenodon punctatus) had a melatonin rhythm of much lower amplitude than did the diurnal desert-adapted sleepy lizard (Tiliqua rugosa). Experiments in controlled laboratory environments showed that, although both species are capable of attaining a comparable melatonin peak (approximately 750 pmol/l), the threshold temperature at which a significant daily rhythm occurs is approximately 15 degrees C in S. punctatus compared with approximately 25 degrees C in T. rugosa. This difference probably reflects the disparate thermoregulatory adaptations of the two species, S. punctatus favoring mean activity temperatures of 11.5 degrees C and T. rugosa, 32.5 degrees C. In ectotherms such as reptiles, therefore, species-typical thermoregulatory behavior may provide thermal cues that interact with photoperiod to provide the appropriate melatonin signal for the regulation of annual physiological cycles.


1966 ◽  
Vol 44 (4) ◽  
pp. 511-517 ◽  
Author(s):  
D. M. Ogilvie ◽  
R. H. Stinson

Adult animals have been used for most of the previous mammalian temperature selection studies, and relatively few systematic observations have been made with young animals. In this investigation, laboratory mice (Mus musculus), ranging in age from 1 to 84 days, were studied in a horizontal temperature gradient established along a 5-ft copper bar. Despite poorly developed locomotion and cold immobilization, it was shown that the temperature selection response is present at birth. The initially high level of selection appeared to be maintained for about 2 weeks, after which it began to decrease, rapidly at first, and then more slowly until the adult level was reached.


2019 ◽  
Vol 92 (1) ◽  
pp. 71-79 ◽  
Author(s):  
Susan Y. S. Wang ◽  
Glenn J. Tattersall ◽  
Janet Koprivnikar

1967 ◽  
Vol 24 (7) ◽  
pp. 1507-1513 ◽  
Author(s):  
M. Yaqub Javaid ◽  
John M. Anderson

The selected temperature for Atlantic salmon and rainbow trout, as determined in a horizontal gradient, increases with acclimation temperature over the acclimation range 5–20 C for salmon and 10–20 C for trout. The final preferendum for salmon is about 17 C. The results for rainbow trout suggest that the type of gradient used, i.e. vertical or horizontal, has a marked influence on the experimentally determined relation between acclimation temperature and selected temperature.


Sign in / Sign up

Export Citation Format

Share Document