Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across Africa
The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural, physiological and even morphological mechanisms. However, the role of glabrous skin in this respect has been marginally addressed so far. The Helmeted Guineafowl (Numida meleagris) is a landfowl distri...
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KeAi Communications Co., Ltd.
2022-01-01
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| Series: | Avian Research |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2053716622000433 |
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| author | Johann H. Van Niekerk Rodrigo Megía-Palma Giovanni Forcina |
| author_facet | Johann H. Van Niekerk Rodrigo Megía-Palma Giovanni Forcina |
| author_sort | Johann H. Van Niekerk |
| collection | DOAJ |
| description | The responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural, physiological and even morphological mechanisms. However, the role of glabrous skin in this respect has been marginally addressed so far. The Helmeted Guineafowl (Numida meleagris) is a landfowl distributed across Sub-Saharan Africa with eight traditionally recognised extant subspecies. Among the most prominent morphological traits underlying intraspecific variability are size and pigmentation of the bare throat skin (or sack), which might be related to the different habitats and environmental conditions across its wide range. In order to explore the Helmeted Guineafowl range-wide sack variation and pigmentation in relation to thermoregulation and sexual signalling, we collected morphometric and environmental information for N. m. coronata integrating field data with the inspection of photographic material encompassing seven subspecies and environmental information from their habitats. Field data evidenced that sack size was significantly correlated with ambient temperature, thus pointing to a likely involvement of the throat sack in thermoregulation. When the pictorial data from all subspecies were pooled, sack size correlated negatively with biomass, rainfall and humidity, while a positive correlation was found with annual solar irradiation. Sack size correlated positively with monthly temperature variation among the blue-throated subspecies from southern Africa as opposed to the black-throated subspecies ranging north to Zambia and Mozambique. Still, in this latter group the sack was often larger during winter months, possibly to maximise solar radiation absorbance. Noteworthy, sack size was related to sex dimorphism in two subspecies. Sack morphology and colour in the Helmeted Guineafowl likely modulate body temperature by evaporative cooling or heating upon needs, but in some subspecies it is also seemingly related to sexual signalling. Additional studies are needed to fully understand the multifunctionality of this important morphological feature in this species. |
| first_indexed | 2024-04-12T01:15:59Z |
| format | Article |
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| issn | 2053-7166 |
| language | English |
| last_indexed | 2024-04-12T01:15:59Z |
| publishDate | 2022-01-01 |
| publisher | KeAi Communications Co., Ltd. |
| record_format | Article |
| series | Avian Research |
| spelling | doaj.art-e7a10496bd984ae1b33e66e49fa25fc72022-12-22T03:53:57ZengKeAi Communications Co., Ltd.Avian Research2053-71662022-01-0113100047Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across AfricaJohann H. Van Niekerk0Rodrigo Megía-Palma1Giovanni Forcina2Department of Environmental Sciences, College of Agriculture and Environmental Sciences, University of South Africa, P.O. Box 392, Pretoria, 0003, South Africa; Corresponding author.Universidad de Alcalá (UAH), Department of Biomedicine and Biotechnology, School of Pharmacy, A-2 Highway, km 33.600, 28805, Alcalá de Henares, Madrid, Spain; Universidad de Alcalá (UAH), Global Change Ecology and Evolution Research Group (GloCEE), Departamento de Ciencias de la Vida, 28805, Alcalá de Henares, Madrid, Spain; CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661, Vairão, Portugal; BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661, Vairão, PortugalUniversidad de Alcalá (UAH), Global Change Ecology and Evolution Research Group (GloCEE), Departamento de Ciencias de la Vida, 28805, Alcalá de Henares, Madrid, Spain; CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661, Vairão, Portugal; BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661, Vairão, PortugalThe responses of ground-dwelling birds to heat and cold stress encompass a variety of behavioural, physiological and even morphological mechanisms. However, the role of glabrous skin in this respect has been marginally addressed so far. The Helmeted Guineafowl (Numida meleagris) is a landfowl distributed across Sub-Saharan Africa with eight traditionally recognised extant subspecies. Among the most prominent morphological traits underlying intraspecific variability are size and pigmentation of the bare throat skin (or sack), which might be related to the different habitats and environmental conditions across its wide range. In order to explore the Helmeted Guineafowl range-wide sack variation and pigmentation in relation to thermoregulation and sexual signalling, we collected morphometric and environmental information for N. m. coronata integrating field data with the inspection of photographic material encompassing seven subspecies and environmental information from their habitats. Field data evidenced that sack size was significantly correlated with ambient temperature, thus pointing to a likely involvement of the throat sack in thermoregulation. When the pictorial data from all subspecies were pooled, sack size correlated negatively with biomass, rainfall and humidity, while a positive correlation was found with annual solar irradiation. Sack size correlated positively with monthly temperature variation among the blue-throated subspecies from southern Africa as opposed to the black-throated subspecies ranging north to Zambia and Mozambique. Still, in this latter group the sack was often larger during winter months, possibly to maximise solar radiation absorbance. Noteworthy, sack size was related to sex dimorphism in two subspecies. Sack morphology and colour in the Helmeted Guineafowl likely modulate body temperature by evaporative cooling or heating upon needs, but in some subspecies it is also seemingly related to sexual signalling. Additional studies are needed to fully understand the multifunctionality of this important morphological feature in this species.http://www.sciencedirect.com/science/article/pii/S2053716622000433Evaporative coolingHelmeted guineafowlSexual size dimorphismSub-Saharan AfricaThermoregulationThroat sack |
| spellingShingle | Johann H. Van Niekerk Rodrigo Megía-Palma Giovanni Forcina Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across Africa Avian Research Evaporative cooling Helmeted guineafowl Sexual size dimorphism Sub-Saharan Africa Thermoregulation Throat sack |
| title | Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across Africa |
| title_full | Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across Africa |
| title_fullStr | Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across Africa |
| title_full_unstemmed | Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across Africa |
| title_short | Thermoregulatory function and sexual dimorphism of the throat sack in Helmeted Guineafowl (Numida meleagris) across Africa |
| title_sort | thermoregulatory function and sexual dimorphism of the throat sack in helmeted guineafowl numida meleagris across africa |
| topic | Evaporative cooling Helmeted guineafowl Sexual size dimorphism Sub-Saharan Africa Thermoregulation Throat sack |
| url | http://www.sciencedirect.com/science/article/pii/S2053716622000433 |
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