scholarly journals Behavioral adaptations in Ameivula ocellifera (Squamata: Teiidae) in response to thermal environmental changes

2019 ◽  
Vol 18 (2) ◽  
pp. 225-240
Author(s):  
Raul Fernandes Dantas Sales ◽  
Eliza Maria Xavier Freire
Keyword(s):  
Body Temperature ◽  
Rainy Season ◽  
Environmental Changes ◽  
Northeastern Brazil ◽  
Body Temperatures ◽  
Thermal Environments ◽  
Behavioral Adaptations ◽  
Air Temperatures ◽  
External Sources ◽  
Regulate Body Temperature

Behavioral adaptations in Ameivula ocellifera (Squamata: Teiidae) in response to thermal environmental changes. Lizards rely on external sources to regulate body temperature, but in many species, it is not known whether lizards are able to change their thermoregulatory behaviors in response to variations in thermal environments. The seasonal thermal ecology of three populations of the Brazilian whiptail lizard, Ameivula ocellifera, in northeastern Brazil (two Caatinga sites and one in the Atlantic Forest) was investigated. The relationships between body temperature and microhabitat temperatures (substrate and air), and between body temperature and thermoregulatory behavior (i.e., time of exposure to sunlight classes and time spent basking) were explored. The average body temperatures of the lizards were 38–39°C; these neither varied seasonally nor among populations. Substrate and air temperatures are lower at the natural Caatinga site, and lizards in there spent less time in the shade and more time exposed to the sun. Microhabitat temperatures vary seasonally in natural Caatinga; they are lower in the rainy season, when lizards spent more time exposed to sun and less time in fltered sun. Lizard body temperatures exceeded microhabitat temperatures in the rainy season in all three populations; however, they did not exceed substrate temperature in the dry season. In each of the populations, lizards with low body temperatures during cloudy conditions spent more time basking. Thus, A. ocellifera adjusts its body temperature behaviorally to compensate for seasonal changes in environmental temperatures, as well as geographic thermal variation throughout its range.

Body temperature regulation and oxygen consumption in young chicks fed thyroid hormone

1991 ◽  
Vol 69 (7) ◽  
pp. 1842-1847 ◽  
Author(s):  
Gregory K. Snyder ◽  
Joseph R. Coelho ◽  
Dalan R. Jensen
Keyword(s):  
Oxygen Consumption ◽  
Thyroid Hormone ◽  
Body Temperature ◽  
Ambient Temperature ◽  
Cold Exposure ◽  
Elevated Serum ◽  
Body Temperatures ◽  
Serum Thyroid Hormone ◽  
Regulate Body Temperature ◽  
Young Chicks

In chicks the ability to regulate body temperature to adult levels develops during the first 2 weeks of life. We examined whether the ability of young chicks to regulate body temperature is increased by elevated levels of the thyroid hormone 3,3′5-triiodothyronine. By 13 days following hatch, body temperatures of chicks were not significantly different from those expected for adult birds. Furthermore, at an ambient temperature of 10 °C, 13-day-old control chicks were able to maintain body temperature, and elevated serum thyroid hormone levels did not increase rates of oxygen consumption or body temperature above control values. Six-day-old chicks had body temperatures that were significantly lower than those of the 13-day-old chicks and were not able to regulate body temperature when exposed to an ambient temperature of 10 °C. On the other hand, 6-day-old chicks with elevated serum thyroid hormone had significantly higher rates of oxygen consumption than 6-day-old control chicks, and were able to maintain constant body temperatures during cold exposure. The increased oxygen consumption rates and improved ability to regulate body temperature during cold exposure were correlated with increased citrate synthase activity in skeletal muscle. Our results support the argument that thyroid hormones play an important role in the development of thermoregulatory ability in neonate birds by stimulating enzyme activities associated with aerobic metabolism.

Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude II. Responses in body, skin and coat temperatures, cardio-respiratory frequencies and rate of moisture secretion of ewes to the diurnal fluctuation in ambient temperature during the hottest part of the year

1960 ◽  
Vol 55 (3) ◽  
pp. 295-302 ◽  
Author(s):  
R. B. Symington
Keyword(s):  
Body Temperature ◽  
Ambient Temperature ◽  
Skin Temperature ◽  
Skin Surface ◽  
Diurnal Fluctuation ◽  
Body Temperatures ◽  
Solar Insolation ◽  
Air Temperatures ◽  
Insensible Perspiration ◽  
Artificial Heat

Responses in body, skin and coat temperatures, cardio-respiratory frequencies and rate of moisture secretion of ewes of three breeds to the diurnal fluctuation in ambient temperature were recorded in the presence and absence of drinking water during the hottest part of the Rhodesian year.1. At 7.0 a.m. body temperatures were: Merino 102·8° F.; Persian 102·2° F. and Native 101·5° F. Between 7·0 a.m. and 1·0 p.m. body temperature rose almost equally in Persians and Natives and fell slightly in Merinos. Change in body temperature between 7.0 a.m. and 1.0 p.m. was not affected significantly by availability of water nor age of ewe, but varied with type of thermal burden (i.e. solar insolation only v. solar insolation plus artificial heat) when water was not available. Although air temperature fell towards late afternoon body temperature of Merinos and Natives rose appreciably, that of Persians only slightly.2. At 7·0 a.m. respiratory rates were (cyc./min.): Merino 59·6; Persian 43·0; Native 29·9. Increase in rate of respiration was the main thermolytic mechanism in all breeds. Merinos had a lower threshold of respiratory response to rising ambient temperature than either hair breed but increase in rate of respiration between 7.0 a.m. and 1.0 p.m. did not differ significantly with breed or age.3. No breed appeared to use the peripheral blood system in thermoregulation. Cardio-frequency, as a measure of this blood flow, remained almost constant with a slight tendency to fall with rise in ambient temperature.4. In all breeds skin temperature was related to ambient and body temperatures; consequently the diurnal fluctuation in skin temperature differed in wool and hair breeds. When thermal burden was greatest Merino skin temperature fell, that of hair breeds did not.Except at 11.0 a.m. there was a gradient between rectal, skin and air temperatures. Direct elimination of heat was thus possible for 23 hr. each day.5. In hair breeds moisture secretion depended on insensible perspiration; consequently, rate of moisture secretion changed with body and air temperatures. In Merinos moisture for skin surface evaporation was provided by sensible and insensible perspiration. Natives may be able to sweat at temperatures higher than those recorded but it is unlikely Persians have a sweating mechanism.6. In all breeds coat temperature was related closely to ambient temperature and changes in solar conditions evoked immediate response in coat temperature. Merino fleece apparently stabilized skin temperature whereas Persian and Native hair did not.

Parental Care and the Development of Thermoregulation in Red Junglefowl

Behaviour ◽  
1981 ◽  
Vol 76 (3-4) ◽  
pp. 250-279 ◽  
Author(s):  
D.F. Sherry
Keyword(s):  
Body Temperature ◽  
Air Temperature ◽  
Behavioural Thermoregulation ◽  
Thermal Environments ◽  
Air Temperatures ◽  
Red Junglefowl ◽  
Wide Range ◽  
In The Wild ◽  
Elevated Body Temperature ◽  
Brooding Behaviour

AbstractFew newly hatched birds are capable of maintaining a stable elevated body temperature at air temperatures encountered in the wild. The brooding behaviour of young red junglefowl (Gallus gallus spadiceus) and the changes in brooding that occur with the development of homeothermy were examined to determine the importance of thermal factors in parent-young contact. A fall in cooling rate and a rise in body temperature occur in junglefowl chicks in the days following hatching, and the young spend less time in contact with the hen as these changes occur. The length of brooding bouts is jointly determined by air temperature and the age of the young. Additional brooding at low air temperatures did not affect feeding by the parent or young. The general features of chick brooding persist when the hen is replaced with a model with brood patches at a temperature normal for maternal junglefowl. Brooding and huddling with other young are alternative thermoregulatory strategies. Behavioural thermoregulation by the young accounted for most features of contact between parent and young. Termination of brooding by the parent and reduction of chick heat loss by changes in parental posture may also influence brooding. Reliance on behavioural thermoregulation may permit development in a wide range of thermal environments.

Effects of gap-based silviculture on thermal biology of a terrestrial reptile

2018 ◽  
Vol 45 (1) ◽  
pp. 72 ◽  
Author(s):  
Mickey Agha ◽  
Brian D. Todd ◽  
Ben Augustine ◽  
John M. Lhotka ◽  
Leo J. Fleckenstein ◽  
...  
Keyword(s):  
Body Temperature ◽  
Time Of Day ◽  
Canopy Gaps ◽  
Body Temperatures ◽  
Thermal Environments ◽  
Silvicultural Practices ◽  
Box Turtles ◽  
Box Turtle ◽  
Eastern Box Turtles ◽  
Environmental Temperatures

Context Terrestrial reptiles require varied thermal environments to promote optimal physiological performance, growth, reproduction, and survival. Aims Our study was designed to determine whether gap-based silvicultural practices offer suitable thermal environments for eastern box turtles (Terrapene carolina) by examining environmental temperature variation and body temperature of eastern box turtles in, and adjacent to, canopy gaps. Methods We recorded box turtle body temperature from 20 radio-tracked turtles and environmental temperatures (canopy gaps and undisturbed habitat) using temperature loggers from June to September 2014 in a managed forest after canopy gaps (0.28–1.13 ha gap–1) were created via gap-based silviculture. Key results Over the four-month study period, gap temperatures were generally higher than adjacent undisturbed microhabitats. Box turtle body temperatures were closely correlated with environmental temperatures in undisturbed habitat in June and July. Turtle body temperatures were, however, closely correlated with environmental temperatures in canopy gaps in August and September. In addition, box turtles in our study had activity areas that overlapped canopy gaps from 0 to 65%, depending on the individual. As percentage overlap of canopy gaps increased, turtle body temperatures were increasingly correlated with canopy gap temperatures. Furthermore, as percentage overlap of canopy gaps increased, daily mean body temperature records consistently stayed within the preferred box turtle body temperature range (20.2–26.2°C). Conclusions Our study suggests that gap-based silviculture can create thermally compatible environments for box turtles depending on the time of day and year, and that box turtles use these microhabitats to thermoregulate. Implications The application of relatively small-scale silvicultural practices (≤1 ha gap–1) that provide heterogeneity in forest structure, composition, and function may be a useful alternative to clearcutting and other intensive harvesting methods that are associated with declines in terrestrial reptile populations.

Effect of environmental temperature on body temperature and metabolic heat production in a heterothermic rodent,Spermophilus tereticaudus

2002 ◽  
Vol 205 (14) ◽  
pp. 2099-2105 ◽  
Author(s):  
K. Mark Wooden ◽  
Glenn E. Walsberg
Keyword(s):  
Body Temperature ◽  
Ground Squirrel ◽  
Environmental Temperature ◽  
Body Temperatures ◽  
Metabolic Heat ◽  
Thermoneutral Zone ◽  
Air Temperatures ◽  
The Mean ◽  
Maximum Body ◽  
Over Time

SUMMARYThis study quantifies the thermoregulatory ability and energetics of a mammal, the round-tailed ground squirrel Spermophilus tereticaudus,that can relax thermoregulatory limits without becoming inactive. We measured body temperature and metabolic rate in animals exposed for short periods (1 h)to air temperatures ranging from 10 to 45 °C and for long periods (8 h) to air temperatures ranging from 10 to 30 °C. Within 45 min of exposure to air temperatures ranging from 10 to 45 °C, the mean body temperatures of alert and responsive animals ranged from 32.1 °C(Tair=10 °C) to 40.4 °C(Tair=45 °C). This thermolability provided significant energetic savings below the thermoneutral zone, ranging from 0.63 W (18 %) at 10 °C to 0.43 W (43 %) at 30 °C. When exposed for 8 h to air temperatures between 10 and 30 °C, animals varied their body temperature significantly over time. At all air temperatures, the lowest body temperature(maintained for at least 1 h) was 31.2 °C. The highest body temperatures(maintained for at least 1 h) were 33.6 °C at 10 °C, 35.3 °C at 20°C and 36.3 °C at 30 °C. The energetic savings realized by maintaining the minimum rather than the maximum body temperature was 0.80 W(25 %) at 10 °C, 0.71 W (33 %) at 20 °C and 0.40 W (47 %) at 30°C. This study demonstrates in several ways the ability of this species to adjust energy expenditure through heterothermy.

scholarly journals Sun-basking fish benefit from body temperatures that are higher than ambient water

2018 ◽  
Vol 285 (1879) ◽  
pp. 20180639 ◽  
Author(s):  
Oscar Nordahl ◽  
Petter Tibblin ◽  
Per Koch-Schmidt ◽  
Hanna Berggren ◽  
Per Larsson ◽  
...  
Keyword(s):  
Body Temperature ◽  
Climate Change Impacts ◽  
Physical Models ◽  
Future Research ◽  
Ambient Water ◽  
Body Temperatures ◽  
Terrestrial Environments ◽  
Improved Performance ◽  
Regulate Body Temperature ◽  
Significant Mechanism

In terrestrial environments, cold-blooded animals can attain higher body temperatures by sun basking, and thereby potentially benefit from broader niches, improved performance and higher fitness. The higher heat capacity and thermal conductivity of water compared with air have been universally assumed to render heat gain from sun basking impossible for aquatic ectotherms, such that their opportunities to behaviourally regulate body temperature are largely limited to choosing warmer or colder habitats. Here we challenge this paradigm. Using physical models we first show that submerged objects exposed to natural sunlight attain temperatures in excess of ambient water. We next demonstrate that free-ranging carp ( Cyprinus carpio ) can increase their body temperature during aquatic sun basking close to the surface. The temperature excess gained by basking was larger in dark than in pale individuals, increased with behavioural boldness, and was associated with faster growth. Overall, our results establish aquatic sun basking as a novel ecologically significant mechanism for thermoregulation in fish. The discovery of this previously overlooked process has practical implications for aquaculture, offers alternative explanations for behavioural and phenotypic adaptations, will spur future research in fish ecology, and calls for modifications of models concerning climate change impacts on biodiversity in marine and freshwater environments.

CALORIMETRIC DETERMINATION OF AVERAGE BODY TEMPERATURE OF SMALL MAMMALS AND ITS VARIATION WITH ENVIRONMENTAL CONDITIONS

1951 ◽  
Vol 29 (3) ◽  
pp. 224-233 ◽  
Author(s):  
J. S. Hart
Keyword(s):  
Body Temperature ◽  
Heat Production ◽  
Temperature Rise ◽  
Environmental Temperature ◽  
Body Temperatures ◽  
Dewar Flask ◽  
Air Temperatures ◽  
Calorimetric Determination ◽  
Average Body

A method is described for determining average body temperature of mice by placing them immediately after killing in a Dewar flask containing water and recording the temperature rise. Evidence is presented to show that postmortem heat production does not contribute appreciably to the results. Average body temperatures are usually about 2 °C. lower than colonic temperatures except during lethal chilling when average temperatures are frequently higher than colonic. The rise in average body temperature produced by activity increases with environmental temperature. Body temperatures may be lower during activity than during rest at cold air temperatures.

scholarly journals Child Safety Seat Cooling System

2019 ◽  
Vol 8 (6S4) ◽  
pp. 810-814
Keyword(s):  
Body Temperature ◽  
Cooling System ◽  
The Body ◽  
Child Safety ◽  
Test Results ◽  
Body Temperatures ◽  
Thermoelectric Cooling ◽  
Air Convection ◽  
Air Temperatures ◽  
Safety Seat

Vehicle thriving remains an undeniable vehicle issue for bosses, purchasers, and government controllers. One region that favorable circumstances thought is the flourishing issue of when a tyke is dismissed in a left vehicle all through the mid year months when the enveloping air temperatures are additionally smoking. Wounds and passings of baby kids, youthful youngsters, and progressively prepared grown-ups have occurred because of raised body temperatures for conceded time portions. One proposed strategy is the plan of a vehicle success arrange that offers vaporous warm security to the occupant. This seat highlights thermoelectric cooling and obliged air convection to keep up the body temperature inside elegant degrees quickly. In this paper, a framework warm model and test results are shown to support the adequacy of the thermoelectric-based thriving structure. The exploratory framework shows the limit of keeping up kept lodge air temperatures underneath fundamental survivability edges in a shut left vehicle for down to 95 minutes. This tends to a 85% advancement over standard youth seating units, in lodge temperatures up to 69 ◦C, for a copied 7 kg tyke. Summary Terms Analysis, vehicle flourishing, kid security mastermind, appearing, occupant assurance, test, thermoelectric contraptions

Radiotelemetry of body temperatures of free-ranging snapping turtles (Chelydra serpentina) during summer

1990 ◽  
Vol 68 (8) ◽  
pp. 1659-1663 ◽  
Author(s):  
Gregory P. Brown ◽  
Ronald J. Brooks ◽  
James A. Layfield
Keyword(s):  
Body Temperature ◽  
Chelydra Serpentina ◽  
Body Temperatures ◽  
Mean Body Temperature ◽  
Mean Temperature ◽  
Snapping Turtles ◽  
Air Temperatures ◽  
Foraging Tactics ◽  
The Mean ◽  
Free Ranging

We wished to determine whether free-ranging snapping turtles (Chelydra serpentina) would use aquatic and atmospheric basking to maintain body temperature at the mean temperature (28–30 °C) selected by snapping turtles placed in a controlled aquatic thermal gradient. Body temperatures from eight adult snapping turtles in three different lakes in Algonquin Provincial Park were monitored by radiotelemetry during July and August 1987. Mean body temperature of all eight turtles over the study period was 22.7 °C, and mean temperature of every individual was well below the reported mean selected temperature for this species. The turtles did not maintain body temperatures near the available maximum environmental temperature. The mean body temperatures of the turtles were not significantly different among the three study lakes although these lakes had different physical characteristics. Similarly, there were no significant differences, among individual turtles, between air temperatures or operative environmental temperatures recorded concurrently with their body temperatures Nevertheless, mean body temperatures differed significantly among individuals; foraging tactics, metabolic rates, and home range structure may account for these differences.

Thermoregulation of the lizard Barisia imbricata at altitudinal extremes

2019 ◽  
Vol 40 (3) ◽  
pp. 349-360
Author(s):  
Natalia Fierro-Estrada ◽  
Yasmin Guadalupe González González ◽  
Donald B. Miles ◽  
Margarita Martínez Gómez ◽  
Andrés García ◽  
...  
Keyword(s):  
Body Temperature ◽  
Narrow Range ◽  
Thermal Ecology ◽  
Body Temperatures ◽  
Mean Body Temperature ◽  
Thermal Requirements ◽  
Air Temperatures ◽  
Preferred Temperatures ◽  
Environmental Temperatures ◽  
Two Populations

Abstract Ambient temperature is a primary factor affecting the physiology and activity of reptiles. Thermoregulation involves a series of mechanisms to maintain an organism’s body temperature within a narrow range. The study of thermal ecology of lizards is relevant for understanding their distribution, life history, ecology and thermal requirements. Moreover, determining how species are able to attain physiologically active body temperatures in challenging environments is necessary for assessing the risk of extinction due to climate change, especially for threatened endemic species. We evaluated and compared the thermal ecology of two populations of the viviparous lizard Barisia imbricata, at contrasting elevations (2200 and 3700 m). We obtained variation in thermal data from winter through autumn for multiple years. We determined thermal efficiency indices based on field active body temperatures, preferred temperatures (in a thermal gradient), and operative environmental temperatures (according to null models). We also recorded substrate and air temperatures at the time of capture. Mean body temperature of both populations showed a positive correlation with environmental temperatures. We found significant seasonal differences in body temperature in both populations, and between body temperatures of the two populations. Our results suggest that B. imbricata is an eurythermic species and can thermoregulate actively at any given time. However, when environmental temperatures are within the range of preferred temperatures, the species does not engage in thermoregulatory behavior. This information expands knowledge on the range of possible thermal responses to environmental variation within a species.

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