Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane
Abstract It has been proposed that there is a thermal cost of the mane to male lions, potentially leading to increased body surface temperatures (Ts), increased sperm abnormalities, and to lower food intake during hot summer months. To test whether a mane imposes thermal costs on males, we measured...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Wiley
2017-01-01
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| Series: | Ecology and Evolution |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ece3.2556 |
| _version_ | 1828717957683871744 |
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| author | Paul Trethowan Andrea Fuller Anna Haw Tom Hart Andrew Markham Andrew Loveridge Robyn Hetem Byron duPreez David W. Macdonald |
| author_facet | Paul Trethowan Andrea Fuller Anna Haw Tom Hart Andrew Markham Andrew Loveridge Robyn Hetem Byron duPreez David W. Macdonald |
| author_sort | Paul Trethowan |
| collection | DOAJ |
| description | Abstract It has been proposed that there is a thermal cost of the mane to male lions, potentially leading to increased body surface temperatures (Ts), increased sperm abnormalities, and to lower food intake during hot summer months. To test whether a mane imposes thermal costs on males, we measured core body temperature (Tb) continuously for approximately 1 year in 18 free‐living lions. There was no difference in the 24‐hr maximum Tb of males (n = 12) and females (n = 6), and males had a 24‐hr mean Tb that was 0.2 ± 0.1°C lower than females after correcting for seasonal effects. Although feeding on a particular day increased 24‐hr mean and 24‐hr maximum Tb, this phenomenon was true of both male and female lions, and females had higher 24‐hr mean and 24‐hr maximum Tb than males, on both days when lions did not feed, and on days when lions did feed. Twenty‐four‐hour Tb was not influenced by mane length or color, and 24‐hr mean Tb was negatively correlated with mane length. These data contradict the suggestion that there exists a thermal cost to male lions in possessing a long dark mane, but do not preclude the possibility that males compensate for a mane with increased heat loss. The increased insulation caused by a mane does not necessarily have to impair heat loss by males, which in hot environments is primarily through respiratory evaporative cooling, nor does in necessarily lead to increased heat gain, as lions are nocturnal and seek shade during the day. The mane may even act as a heat shield by increasing insulation. However, dominant male lions frequent water points more than twice as often as females, raising the possibility that male lions are increasing water uptake to facilitate increased evaporative cooling. The question of whether male lions with manes compensate for a thermal cost to the mane remains unresolved, but male lions with access to water do not have higher Tb than females or males with smaller manes. |
| first_indexed | 2024-03-12T14:35:56Z |
| format | Article |
| id | doaj.art-230ae5d8478f490886a61652c069c85f |
| institution | Directory Open Access Journal |
| issn | 2045-7758 |
| language | English |
| last_indexed | 2024-03-12T14:35:56Z |
| publishDate | 2017-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecology and Evolution |
| spelling | doaj.art-230ae5d8478f490886a61652c069c85f2023-08-17T06:04:36ZengWileyEcology and Evolution2045-77582017-01-017125326210.1002/ece3.2556Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ manePaul Trethowan0Andrea Fuller1Anna Haw2Tom Hart3Andrew Markham4Andrew Loveridge5Robyn Hetem6Byron duPreez7David W. Macdonald8Wildlife Conservation Research Unit The Recanati‐Kaplan Centre Department of Zoology University of Oxford Oxford UKBrain Function Research Group School of Physiology Faculty of Health Sciences University of the Witwatersrand Johannesburg South AfricaBrain Function Research Group School of Physiology Faculty of Health Sciences University of the Witwatersrand Johannesburg South AfricaDepartment of Zoology University of Oxford Oxford UKDepartment of Computer Sciences University of Oxford Oxford UKWildlife Conservation Research Unit The Recanati‐Kaplan Centre Department of Zoology University of Oxford Oxford UKBrain Function Research Group School of Physiology Faculty of Health Sciences University of the Witwatersrand Johannesburg South AfricaWildlife Conservation Research Unit The Recanati‐Kaplan Centre Department of Zoology University of Oxford Oxford UKWildlife Conservation Research Unit The Recanati‐Kaplan Centre Department of Zoology University of Oxford Oxford UKAbstract It has been proposed that there is a thermal cost of the mane to male lions, potentially leading to increased body surface temperatures (Ts), increased sperm abnormalities, and to lower food intake during hot summer months. To test whether a mane imposes thermal costs on males, we measured core body temperature (Tb) continuously for approximately 1 year in 18 free‐living lions. There was no difference in the 24‐hr maximum Tb of males (n = 12) and females (n = 6), and males had a 24‐hr mean Tb that was 0.2 ± 0.1°C lower than females after correcting for seasonal effects. Although feeding on a particular day increased 24‐hr mean and 24‐hr maximum Tb, this phenomenon was true of both male and female lions, and females had higher 24‐hr mean and 24‐hr maximum Tb than males, on both days when lions did not feed, and on days when lions did feed. Twenty‐four‐hour Tb was not influenced by mane length or color, and 24‐hr mean Tb was negatively correlated with mane length. These data contradict the suggestion that there exists a thermal cost to male lions in possessing a long dark mane, but do not preclude the possibility that males compensate for a mane with increased heat loss. The increased insulation caused by a mane does not necessarily have to impair heat loss by males, which in hot environments is primarily through respiratory evaporative cooling, nor does in necessarily lead to increased heat gain, as lions are nocturnal and seek shade during the day. The mane may even act as a heat shield by increasing insulation. However, dominant male lions frequent water points more than twice as often as females, raising the possibility that male lions are increasing water uptake to facilitate increased evaporative cooling. The question of whether male lions with manes compensate for a thermal cost to the mane remains unresolved, but male lions with access to water do not have higher Tb than females or males with smaller manes.https://doi.org/10.1002/ece3.2556body temperatureecological functionPanthera leothermal biology |
| spellingShingle | Paul Trethowan Andrea Fuller Anna Haw Tom Hart Andrew Markham Andrew Loveridge Robyn Hetem Byron duPreez David W. Macdonald Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane Ecology and Evolution body temperature ecological function Panthera leo thermal biology |
| title | Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane |
| title_full | Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane |
| title_fullStr | Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane |
| title_full_unstemmed | Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane |
| title_short | Getting to the core: Internal body temperatures help reveal the ecological function and thermal implications of the lions’ mane |
| title_sort | getting to the core internal body temperatures help reveal the ecological function and thermal implications of the lions mane |
| topic | body temperature ecological function Panthera leo thermal biology |
| url | https://doi.org/10.1002/ece3.2556 |
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