Related Experiment Video
Updated: Jul 19, 2026
06:57
Determining Basal Energy Expenditure and the Capacity of Thermogenic Adipocytes to Expend Energy in Obese Mice
Published on: November 11, 2021
Rewarming rates and thermogenesis in hibernating echidnas
Stewart C Nicol1, Niels A Andersen
1Anatomy and Physiology, University of Tasmania, Private Bag 24, Hobart, TAS 7001, Australia. s.c.nicol@utas.edu.au
Summary
Free-ranging echidnas exhibit significant body temperature fluctuations, with rewarming rates dependent on initial temperature. This study quantifies their thermoregulation and metabolic response during temperature recovery.
Area of Science:
- Zoology
- Physiology
- Thermoregulation
Background:
- Echidnas (Tachyglossus aculeatus) are monotremes with unique physiological adaptations.
- Understanding their thermoregulation is crucial for conservation and evolutionary biology.
Purpose of the Study:
- To measure and analyze body temperature (Tb) patterns in free-ranging echidnas.
- To investigate the dynamics of rewarming events and associated metabolic rates.
Main Methods:
- Implanted data-loggers to record Tb in 14 free-ranging echidnas over extended periods.
- Analysis of rewarming events, calculating rewarming time, rate, and peak oxygen consumption.
- Utilized plots of Tb change rate versus Tb for data analysis.
Main Results:
- Recorded an average of 1020 days of Tb data per animal.
- Observed a wide Tb range from 4.7°C to an average maximum of 35.3°C.
- Rewarming time correlated with initial Tb; peak rewarming rate was 7.2°C/h, 9 times basal metabolic rate.
Conclusions:
- Echidnas display significant thermoregulatory flexibility.
- Rewarming is an energetically costly process, requiring substantial metabolic effort.
- Graphical analysis of Tb change provides an effective tool for studying echidna thermoregulation.
Related Concept Videos
01:26Thermoregulation
The human body has a sophisticated thermoregulation system that employs negative feedback mechanisms to maintain an optimal core temperature. When the core temperature drops, peripheral and central thermoreceptors send signals to the hypothalamus, activating the heat-promoting center. This center triggers several responses aimed at increasing the core temperature. First, vasoconstriction reduces the flow of warm blood from internal organs to the skin so that the heat is not lost from the skin,...
01:25Body Temperature
The body's temperature, measured in degrees, is determined by the balance between heat production and dissipation to the surrounding environment. For instance, if exercising vigorously, the body will produce more heat, causing sweat and dissipating that heat. Despite extreme environmental conditions and physical exertion, the human temperature-control system maintains a constant core body temperature (the temperature of deep tissues, which are the tissues located beneath the skin and other...
01:07Body Temperature
Body temperature reflects the equilibrium between heat production and heat loss within the body. Most heat is generated by metabolically active tissues, particularly the liver, heart, brain, kidneys, and endocrine organs. At rest, skeletal muscles contribute 20–30% of total heat production, but during vigorous exercise, this can increase up to 30–40 times.
The average body temperature is approximately 37°C (98.6°F) and typically ranges from 36.1–37.2°C (97–99°F), remaining relatively stable...
The average body temperature is approximately 37°C (98.6°F) and typically ranges from 36.1–37.2°C (97–99°F), remaining relatively stable...
01:01Production Efficiency
Net production efficiency (NPE) is the efficiency at which organisms assimilate energy into biomass for the next trophic level. Due to low metabolic rates and less energy spent on thermoregulatory processes, the NPE of ectotherms (cold-blooded animals) is 10 times higher than endotherms (warm-blooded animals).
01:19Mechanism of heat transfer
Understanding heat transfer mechanisms is essential for understanding how our bodies maintain balance in different environmental conditions. When the environment is thermoneutral, the body is in a state of balance, neither using nor releasing energy to maintain its core temperature. However, when the environment is not thermoneutral, the body employs four heat transfer mechanisms to maintain homeostasis: conduction, convection, evaporation, and radiation. These mechanisms facilitate heat...
01:29Decreased Body Temperature
A decreased body temperature can occur in patients with hypothermia and frostbite. Heat loss with extended cold exposure overpowers the body's ability to create heat, resulting in hypothermia. Core temperature readings help classify hypothermia. Mild hypothermia is temperatures between 32 °C (89.6 °F) and 35°C (95 °F) and is caused by impaired thermoregulation. Moderate hypothermia is temperatures between 28 C (82.4 °F) and 32 °C (89.6 °F) caused by sustained extreme cold exposure, and severe...