Heterothermy in large mammals: inevitable or implemented?
Open accessAbstract
Advances in biologging techniques over the past 20 years have allowed for the remote and continuous measurement of body temperatures in free‐living mammals. While there is an abundance of literature on heterothermy in small mammals, fewer studies have investigated the daily variability of body core temperature in larger mammals. Here we review measures of heterothermy and the factors that influence heterothermy in large mammals in their natural habitats, focussing on large mammalian herbivores. The mean 24 h body core temperatures for 17 species of large mammalian herbivores (>10 kg) decreased by ∼1.3°C for each 10‐fold increase in body mass, a relationship that remained significant following phylogenetic correction. The degree of heterothermy, as measured by the 24 h amplitude of body core temperature rhythm, was independent of body mass and appeared to be driven primarily by energy and water limitations. When faced with the competing demands of osmoregulation, energy acquisition and water or energy use for thermoregulation, large mammalian herbivores appear to relax the precision of thermoregulation thereby conserving body water and energy. Such relaxation may entail a cost in that an animal moves closer to its thermal limits for performance. Maintaining homeostasis requires trade‐offs between regulated systems, and homeothermy apparently is not accorded the highest priority; large mammals are able to maintain optimal homeothermy only if they are well nourished, hydrated, and not compromised energetically. We propose that the amplitude of the 24 h rhythm of body core temperature provides a useful index of any compromise experienced by a free‐living large mammal and may predict the performance and fitness of an animal.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The amplitude of the 24-h rhythm of body temperature has been proposed as a proxy for the physiological welfare of mammals, with many mammals exhibiting homeothermy only when they have sufficient food and water and are not energetically challenged.
“The amplitude of the 24-h rhythm of body temperature has been proposed as a proxy for the physiological welfare of mammals (Hetem et al., 2016; Maloney et al., 2017; Maloney et al., 2019), with many mammals exhibiting homeothermy only when they have sufficient food and water and are not energetically challenged.”
From Temminck’s pangolins relax the precision of body temperature regulation when resources are scarce in a semi-arid environment (2023) · cites this paper as Hetem et al., 2016
Split into 2 atoms — 0 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 1 unverifiable. Expand the claim to see per-atom verdicts.
Experimental — accuracy not yet measuredBy relaxing the precision of body temperature regulation during winter, pangolins seemed to prioritize energy conservation over thermoregulation during a period when food was scarce.
“By relaxing the precision of body temperature regulation during winter, pangolins, like many other mammals (Pereira et al., 2002; Hetem et al., 2016; Theimer et al., 2017; Weyer et al., 2020), seemed to prioritize energy conservation over thermoregulation during a period when food was scarce.”
From Temminck’s pangolins relax the precision of body temperature regulation when resources are scarce in a semi-arid environment (2023) · cites this paper as Hetem et al., 2016
When food becomes less available, nocturnal mammals may respond by reducing their metabolic rate and body temperature, or by switching to diurnal activity.
“When food becomes less available, nocturnal mammals may respond by reducing their metabolic rate and body temperature (Kelm and von Helversen, 2007; Fuller et al., 2016; Hetem et al., 2016), or by switching to diurnal activity (Van der Vinne et al., 2019; Guiden and Orrock, 2020).”
From Temminck’s pangolins relax the precision of body temperature regulation when resources are scarce in a semi-arid environment (2023) · cites this paper as Hetem et al., 2016
No passage from our indexed copy addresses whether nocturnal mammals reduce metabolic rate and body temperature when food becomes less available. Searches for food availability, food scarcity, nocturnal activity, torpor, and metabolic rate returned no relevant passage. The diurnal-activity clause is attributed to other sources, not this paper. (LLM, conf=0.72)
Experimental — accuracy not yet measuredAlthough food energy is important for the maintenance of high body temperatures, sufficient body water is needed for evaporative cooling.
“Although food energy is important for the maintenance of high body temperatures, sufficient body water is needed for evaporative cooling (Ostrowski et al., 2003; Fuller et al., 2016; Hetem et al., 2016).”
From Temminck’s pangolins relax the precision of body temperature regulation when resources are scarce in a semi-arid environment (2023) · cites this paper as Hetem et al., 2016
No passage from the paper’s body was returned for searches on food energy, water availability, and evaporative cooling. The indexed results contain only abstract and bibliographic material, which cannot establish whether the paper supports this claim under the evidence rule. (LLM, conf=0.72)
Experimental — accuracy not yet measuredFood energy is required for mammals to generate the metabolic heat needed to maintain relatively high and constant body temperatures.
“Food energy is required for mammals to generate the metabolic heat needed to maintain relatively high and constant body temperatures (Hetem et al., 2016).”
From Temminck’s pangolins relax the precision of body temperature regulation when resources are scarce in a semi-arid environment (2023) · cites this paper as Hetem et al., 2016
No passage in the supplied matches or retrieved text addresses whether mammals require food energy to produce metabolic heat and maintain high, constant body temperatures. Searches for those terms and related phrasing returned no substantive passage from our copy; the only result was bibliographic metadata. (LLM, conf=0.70)
Experimental — accuracy not yet measured
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Cites
Phylogenies and the Comparative Method
Felsenstein, J. (1985) · The American Naturalist · doi:10.1086/284325 · Cited by 9,793 · see citing works
Scaling: Why is Animal Size so Important?
Schmidt-Nielsen, K. (1984) · doi:10.1017/cbo9781139167826 · Cited by 2,677 · see citing works
Bouchama, A., & Knochel, J. P. (2002) · New England Journal of Medicine · doi:10.1056/nejmra011089 · Cited by 1,898 · see citing works
Thermoregulation: some concepts have changed. Functional architecture of the thermoregulatory system
Romanovsky, A. A. (2007) · American Journal of Physiology-Regulatory, Integrative and Comparative Physiology · doi:10.1152/ajpregu.00668.2006 · Cited by 786 · see citing works
Allometric scaling of mammalian metabolism
White, C. R., & Seymour, R. S. (2005) · Journal of Experimental Biology · doi:10.1242/jeb.01501 · Cited by 433 · cited 1× · see citing works
“Although the allometric scaling of mammalian metabolic rates has been researched thoroughly (for review see White & Seymour, 2005), comparatively little is known about how body size might influence the mean 24 h body core temperature.”
BackgroundRegulation of metabolic rate in Svalbard and Norwegian reindeer
Nilssen, K. J., Sundsfjord, J. A., & Blix, A. S. (1984) · American Journal of Physiology-Regulatory, Integrative and Comparative Physiology · doi:10.1152/ajpregu.1984.247.5.r837 · Cited by 107 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Temperature regulation in women: Effects of the menstrual cycle
Baker, F. C., Siboza, F., & Fuller, A. (2020) · Temperature · doi:10.1080/23328940.2020.1735927 · Cited by 262 · see citing works
Self-citationCircadian rhythmicity of body temperature and metabolism
Refinetti, R. (2020) · Temperature · doi:10.1080/23328940.2020.1743605 · Cited by 155 · see citing works
Panaino, W., Parrini, F., Kamerman, P. R., Hetem, R. S., Meyer, L. C. R., Smith, D., van Dyk, G., & Fuller, A. (2023) · Conservation Physiology · doi:10.1093/conphys/coad068 · Cited by 12 · see citing works
Self-citation
- Authors
- Hetem, R. S., Maloney, S. K., Fuller, A., & Mitchell, D.
- Affiliations
- University of the Witwatersrand (ZA)
- The University of Western Australia (AU)
- Corresponding author
- Hetem, Robyn S.
- Venue
- Biological Reviews
- Publisher
- Wiley
- Published
- 2014-12-17
- Volume
- 91
- Issue
- 1
- Pages
- 187-205
- ISSN
- 0006-3231 (ISSN-L)
- 1464-7931
- 1469-185X
- OpenAlex
- W1503416478
- Cited by
- 100
- References
- 6
- Citations by year
- 2026: 10 · 2025: 9 · 2024: 8 · 2023: 12 · 2022: 6 · 2021: 9 · 2020: 10 · 2019: 13 · 2018: 8 · 2017: 9 · 2016: 5 · 2015: 1
- FWCI
- 0.54
- Type
- journal article
- Language
- en
- Open access
- Licence
- Locations
- Biological reviews/Biological reviews of the Cambridge Philosophical Society (publishedVersion)
- PubMed (publishedVersion)
- UWA Profiles and Research Repository (UWA) (submittedVersion, other-oa)
- Funders
- Australian Research Council
- Topics
- Physical Sciences › Environmental Science › Ecology › Physiological and biochemical adaptations
- Health Sciences › Medicine › Physiology › Thermoregulation and physiological responses
- Life Sciences › Agricultural and Biological Sciences › Animal Science and Zoology › Effects of Environmental Stressors on Livestock
- Keywords
- heterothermy, large mammals, core body temperature, thermoregulation, body mass, herbivores, osmoregulation, water conservation, energy conservation, thermal limits, homeothermy, biologging
- MeSH terms
- Adaptation, Physiological, Animals, Body Temperature Regulation, Mammals, Body Size, Herbivory
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
