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Udino E, Oscos-Snowball MA, Buchanan KL, Mariette MM. A prenatal acoustic signal of heat reduces a biomarker of chronic stress at adulthood across seasons. Front Physiol 2024; 15:1348993. [PMID: 38617060 PMCID: PMC11009423 DOI: 10.3389/fphys.2024.1348993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Accepted: 03/12/2024] [Indexed: 04/16/2024] Open
Abstract
During development, phenotype can be adaptively modulated by environmental conditions, sometimes in the long-term. However, with weather variability increasing under climate change, the potential for maladaptive long-term responses to environmental variations may increase. In the arid-adapted zebra finch, parents emit "heat-calls" when experiencing heat during incubation, which adaptively affects offspring growth in the heat, and adult heat tolerance. This suggests that heat-call exposure may adjust individual phenotype to hot conditions, potentially compromising individual sensitivity to cool weather conditions. To test this hypothesis, we manipulated individual prenatal acoustic and postnatal thermal experiences during development, and sought to assess subsequent chronic responses to thermal fluctuations at adulthood. We thus measured heterophil to lymphocyte (H/L) ratios in adults, when held in outdoor aviaries during two summers and two winters. We found that birds exposed to heat-calls as embryos, had consistently lower H/L ratios than controls at adulthood, indicative of lower chronic stress, irrespective of the season. Nonetheless, in all birds, the H/L ratio did vary with short-term weather fluctuations (2, 5 or 7 days), increasing at more extreme (low and high) air temperatures. In addition, the H/L ratio was higher in males than females. Overall, while H/L ratio may reflect how individuals were being impacted by temperature, heat-call exposed individuals did not show a stronger chronic response in winter, and instead appeared more resilient to thermal variability than control individuals. Our findings therefore suggest that heat-call exposure did not compromise individual sensitivity to low temperatures at adulthood. Our study also reveals that prenatal sound can lead to long-term differences in individual physiology or quality/condition, as reflected by H/L ratios, which are consistent with previously-demonstrated reproductive fitness differences.
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Affiliation(s)
- Eve Udino
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, Australia
- Max Planck Institute for Biological Intelligence, Seewiesen, Germany
| | - Marja A. Oscos-Snowball
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, VIC, Australia
| | - Katherine L. Buchanan
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, Australia
| | - Mylene M. Mariette
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, Australia
- Doñana Biological Station (EBD-CSIC), Sevilla, Spain
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2
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Ruuskanen S. Early-life environmental effects on birds: epigenetics and microbiome as mechanisms underlying long-lasting phenotypic changes. J Exp Biol 2024; 227:jeb246024. [PMID: 38449325 DOI: 10.1242/jeb.246024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
Although the long-lasting effects of variation in early-life environment have been well documented across organisms, the underlying causal mechanisms are only recently starting to be unraveled. Yet understanding the underlying mechanisms of long-lasting effects can help us predict how organisms will respond to changing environments. Birds offer a great system in which to study developmental plasticity and its underlying mechanisms owing to the production of large external eggs and variation in developmental trajectories, combined with a long tradition of applied, physiological, ecological and evolutionary research. Epigenetic changes (such as DNA methylation) have been suggested to be a key mechanism mediating long-lasting effects of the early-life environment across taxa. More recently, changes in the early-life gut microbiome have been identified as another potential mediator of developmental plasticity. As a first step in understanding whether these mechanisms contribute to developmental plasticity in birds, this Review summarizes how changes in early-life environment (both prenatal and postnatal) influence epigenetic markers and the gut microbiome. The literature shows how both early-life biotic (such as resources and social environment) and abiotic (thermal environment and various anthropogenic stressors) factors modify epigenetic markers and the gut microbiome in birds, yet data concerning many other environmental factors are limited. The causal links of these modifications to lasting phenotypic changes are still scarce, but changes in the hypothalamic-pituitary-adrenal axis have been identified as one putative pathway. This Review identifies several knowledge gaps, including data on the long-term effects, stability of the molecular changes, and lack of diversity in the systems studied, and provides directions for future research.
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Affiliation(s)
- Suvi Ruuskanen
- Department of Biological and Environmental Science, University of Jyväskylä, Survontie 9C, 40500 Jyväskylä, Finland
- Department of Biology, University of Turku, Vesilinnankatu 5, 20500 Turku, Finland
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3
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Subasinghe K, Symonds MRE, Prober SM, Bonnet T, Williams KJ, Ware C, Gardner JL. Spatial variation in avian bill size is associated with temperature extremes in a major radiation of Australian passerines. Proc Biol Sci 2024; 291:20232480. [PMID: 38262606 PMCID: PMC10805599 DOI: 10.1098/rspb.2023.2480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 12/13/2023] [Indexed: 01/25/2024] Open
Abstract
Morphology is integral to body temperature regulation. Recent advances in understanding of thermal physiology suggest a role of the avian bill in thermoregulation. To explore the adaptive significance of bill size for thermoregulation we characterized relationships between bill size and climate extremes. Most previous studies focused on climate means, ignoring frequencies of extremes, and do not reflect thermoregulatory costs experienced over shorter time scales. Using 79 species (9847 museum specimens), we explore how bill size variation is associated with temperature extremes in a large and diverse radiation of Australasian birds, Meliphagides, testing a series of predictions. Overall, across the continent, bill size variation was associated with both climate extremes and means and was most strongly associated with winter temperatures; associations at the level of climate zones differed from continent-wide associations and were complex, yet consistent with physiology and a thermoregulatory role for avian bills. Responses to high summer temperatures were nonlinear suggesting they may be difficult to detect in large-scale continental analyses using previous methodologies. We provide strong evidence that climate extremes have contributed to the evolution of bill morphology in relation to thermoregulation and show the importance of including extremes to understand fine-scale trait variation across space.
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Affiliation(s)
- Kalya Subasinghe
- CSIRO Environment, GPO Box 1700, Canberra, Australian Capital Territory 2601, Australia
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 0200, Australia
- Department of Zoology and Environmental Management, University of Kelaniya, Kelaniya 11600, Sri Lanka
| | - Matthew R. E. Symonds
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria 3125, Australia
| | - Suzanne M. Prober
- CSIRO Environment, GPO Box 1700, Canberra, Australian Capital Territory 2601, Australia
| | - Timothée Bonnet
- Centre d'Etudes Biologiques de Chizé UMR 7372 Université de la Rochelle-CNRS, 405 route de Prissé la Charrière 79360 Villiers en Bois, France
| | - Kristen J. Williams
- CSIRO Environment, GPO Box 1700, Canberra, Australian Capital Territory 2601, Australia
| | - Chris Ware
- CSIRO Environment, University of Tasmania, College Road, Sandy Bay Tas 7005, Australia
| | - Janet L. Gardner
- CSIRO Environment, GPO Box 1700, Canberra, Australian Capital Territory 2601, Australia
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4
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Persson E, Ó Cuív C, Nord A. Thermoregulatory consequences of growing up during a heatwave or a cold snap in Japanese quail. J Exp Biol 2024; 227:jeb246876. [PMID: 38073475 PMCID: PMC10906667 DOI: 10.1242/jeb.246876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 12/06/2023] [Indexed: 01/26/2024]
Abstract
Changes in environmental temperature during development can affect growth, metabolism and temperature tolerance of the offspring. We know little about whether such changes remain to adulthood, which is important to understand the links between climate change, development and fitness. We investigated whether phenotypic consequences of the thermal environment in early life remained in adulthood in two studies on Japanese quail (Coturnix japonica). Birds were raised under simulated heatwave, cold snap or control conditions, from hatching until halfway through the growth period, and then in common garden conditions until reproductively mature. We measured biometric and thermoregulatory [metabolic heat production (MHP), evaporative water and heat loss (EWL, EHL) and body temperature] responses to variation in submaximal air temperature at the end of the thermal acclimation period and in adulthood. Warm birds had lower MHP than control birds at the end of the thermal acclimation period and, in the warmest temperature studied (40°C), also had higher evaporative cooling capacity compared with controls. No analogous responses were recorded in cold birds, although they had higher EWL than controls in all but the highest test temperature. None of the effects found at the end of the heatwave or cold snap period remained until adulthood. This implies that chicks exposed to higher temperatures could be more prepared to counter heat stress as juveniles but that they do not enjoy any advantages of such developmental conditions when facing high temperatures as adults. Conversely, cold temperature does not seem to confer any priming effects in adolescence.
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Affiliation(s)
- Elin Persson
- Lund University, Department of Biology, Section for Evolutionary Ecology, Sölvegatan 37, SE-223 63 Lund, Sweden
| | - Ciarán Ó Cuív
- Lund University, Department of Biology, Section for Evolutionary Ecology, Sölvegatan 37, SE-223 63 Lund, Sweden
| | - Andreas Nord
- Lund University, Department of Biology, Section for Evolutionary Ecology, Sölvegatan 37, SE-223 63 Lund, Sweden
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5
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Auerbach BM, Savell KRR, Agosto ER. Morphology, evolution, and the whole organism imperative: Why evolutionary questions need multi-trait evolutionary quantitative genetics. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023. [PMID: 37060292 DOI: 10.1002/ajpa.24733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 04/16/2023]
Abstract
Since Washburn's New Physical Anthropology, researchers have sought to understand the complexities of morphological evolution among anatomical regions in human and non-human primates. Researchers continue, however, to preferentially use comparative and functional approaches to examine complex traits, but these methods cannot address questions about evolutionary process and often conflate function with fitness. Moreover, researchers also tend to examine anatomical elements in isolation, which implicitly assumes independent evolution among different body regions. In this paper, we argue that questions asked in primate evolution are best examined using multiple anatomical regions subjected to model-bound methods built from an understanding of evolutionary quantitative genetics. A nascent but expanding number of studies over the last two decades use this approach, examining morphological integration, evolvability, and selection modeling. To help readers learn how to use these methods, we review fundamentals of evolutionary processes within a quantitative genetic framework, explore the importance of neutral evolutionary theory, and explain the basics of evolutionary quantitative genetics, namely the calculation of evolutionary potential for multiple traits in response to selection. Leveraging these methods, we demonstrate their use to understand non-independence in possible evolutionary responses across the limbs, limb girdles, and basicranium of humans. Our results show that model-bound quantitative genetic methods can reveal unexpected genetic covariances among traits that create a novel but measurable understanding of evolutionary complexity among multiple traits. We advocate for evolutionary quantitative genetic methods to be a standard whenever appropriate to keep studies of primate morphological evolution relevant for the next seventy years and beyond.
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Affiliation(s)
- Benjamin M Auerbach
- Department of Anthropology, The University of Tennessee, Knoxville, Tennessee, USA
- Department of Ecology and Evolutionary Biology, The University of Tennessee, Knoxville, Tennessee, USA
| | - Kristen R R Savell
- Department of Biology, Sacred Heart University, Fairfield, Connecticut, USA
| | - Elizabeth R Agosto
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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6
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de Oliveira EM, Nascimento ST, Mós JVDN, Roza LDF, Dos Santos TC. Maximum limit of sensible heat dissipation in Japanese quail. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2023; 67:517-526. [PMID: 36723757 DOI: 10.1007/s00484-023-02432-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Surface temperature can be used as a tool for calculating sensible heat transfer. However, it needs to be associated with air temperature to identify the direction of heat flow (gain or loss). This study quantified sensible heat transfer in Japanese quail as a function of operative temperature. The meteorological variables were air temperature, relative humidity, and black globe temperature. Quail surface temperature was measured on 50 adult Coturnix coturnix japonica individuals 270 days old during 8 days by using a thermographic camera. The data were analyzed by the least-squares method to assess the effects of sex (male and female), period of the day (morning and afternoon), and body region (head, body, and feet). Quail surface temperature was strongly correlated with operative temperature. The total sensible heat flow was 64.02 W m-2. The morning period had a mean operative temperature of 22.48 °C, providing a higher gradient between air and quail temperature and thereby producing a higher heat flow (82.19 W m-2). In the afternoon, the heat transfer was lower (45.70 W m-2) because the operative temperature was higher (30.84 °C). Comparison between sexes showed that heat transfer was higher in females (67.37 W m-2) than in males (60.53 W m-2). The head served as an important thermal window, with a heat transfer of 78.24 W m-2, whereas the body and feet had a transfer of 56.80 W m-2. Heat transfer by sensible mechanisms was quantified in Japanese quail. Heat transfer depended greatly on ambient temperature. When the operative temperature was below 28 °C, sensible mechanisms were efficient in dissipating heat to the environment. When the ambient temperature exceeded 29 °C, quail could not effectively dissipate heat to the environment through sensible mechanisms. At 30 °C and above, heat loss shifted to heat gain, causing thermal stress in Japanese quail.
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7
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Allometry reveals trade-offs between Bergmann's and Allen's rules, and different avian adaptive strategies for thermoregulation. Nat Commun 2023; 14:1101. [PMID: 36843121 PMCID: PMC9968716 DOI: 10.1038/s41467-023-36676-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 02/10/2023] [Indexed: 02/28/2023] Open
Abstract
Animals tend to decrease in body size (Bergmann's rule) and elongate appendages (Allen's rule) in warm climates. However, it is unknown whether these patterns depend on each other or constitute independent responses to the thermal environment. Here, based on a global phylogenetic comparative analysis across 99.7% of the world's bird species, we show that the way in which the relative length of unfeathered appendages co-varies with temperature depends on body size and vice versa. First, the larger the body, the greater the increase in beak length with temperature. Second, the temperature-based increase in tarsus length is apparent only in larger birds, whereas in smaller birds, tarsus length decreases with temperature. Third, body size and the length of beak and tarsus interact with each other to predict the species' environmental temperature. These findings suggest that the animals' body size and shape are products of an evolutionary compromise that reflects distinct alternative thermoregulatory adaptations.
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8
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Thermal adaptation best explains Bergmann's and Allen's Rules across ecologically diverse shorebirds. Nat Commun 2022; 13:4727. [PMID: 35953489 PMCID: PMC9372053 DOI: 10.1038/s41467-022-32108-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 07/18/2022] [Indexed: 11/25/2022] Open
Abstract
Bergmann’s and Allen’s rules state that endotherms should be larger and have shorter appendages in cooler climates. However, the drivers of these rules are not clear. Both rules could be explained by adaptation for improved thermoregulation, including plastic responses to temperature in early life. Non-thermal explanations are also plausible as climate impacts other factors that influence size and shape, including starvation risk, predation risk, and foraging ecology. We assess the potential drivers of Bergmann’s and Allen’s rules in 30 shorebird species using extensive field data (>200,000 observations). We show birds in hot, tropical northern Australia have longer bills and smaller bodies than conspecifics in temperate, southern Australia, conforming with both ecogeographical rules. This pattern is consistent across ecologically diverse species, including migratory birds that spend early life in the Arctic. Our findings best support the hypothesis that thermoregulatory adaptation to warm climates drives latitudinal patterns in shorebird size and shape. Global patterns in animal size and shape have been long observed, but their underlying drivers are not well understood. Here the authors suggest latitudinal patterns in shorebird size and shape are best explained by thermal adaptation to warm climates.
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9
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A prenatal acoustic signal of heat affects thermoregulation capacities at adulthood in an arid-adapted bird. Sci Rep 2022; 12:5842. [PMID: 35393484 PMCID: PMC8991222 DOI: 10.1038/s41598-022-09761-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/01/2022] [Indexed: 11/16/2022] Open
Abstract
Understanding animal physiological adaptations for tolerating heat, and the causes of inter-individual variation, is key for predicting climate change impacts on biodiversity. Recently, a novel mechanism for transgenerational heat adaptation was identified in a desert-adapted bird, where parents acoustically signal hot conditions to embryos. Prenatal exposure to “heat-calls” adaptively alters zebra finch development and their thermal preferences in adulthood, suggesting a long-term shift towards a heat-adapted phenotype. However, whether such acoustic experience improves long-term thermoregulatory capacities is unknown. We measured metabolic rate (MR), evaporative water loss (EWL) and body temperature in adults exposed to a stepped profile of progressively higher air temperatures (Ta) between 27 and 44 °C. Remarkably, prenatal acoustic experience affected heat tolerance at adulthood, with heat-call exposed individuals more likely to reach the highest Ta in morning trials. This was despite MR and EWL reaching higher levels at the highest Ta in heat-call individuals, partly driven by a stronger metabolic effect of moderate activity. At lower Ta, however, heat-call exposed individuals had greater relative water economy, as expected. They also better recovered mass lost during morning trials. We therefore provide the first evidence that prenatal acoustic signals have long-term consequences for heat tolerance and physiological adaptation to heat.
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10
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Ballinger MA, Nachman MW. The contribution of genetic and environmental effects to Bergmann’s rule and Allen’s rule in house mice. Am Nat 2022; 199:691-704. [DOI: 10.1086/719028] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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11
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Tapper S, Nocera JJ, Burness G. Body temperature is a repeatable trait in a free-ranging passerine bird. J Exp Biol 2021; 224:272129. [PMID: 34498672 DOI: 10.1242/jeb.243057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 09/03/2021] [Indexed: 12/23/2022]
Abstract
Body temperature (Tb) affects animal function through its influence on rates of biochemical and biophysical reactions, the molecular structures of proteins and tissues, and, ultimately, organismal performance. Despite its importance in driving physiological processes, there are few data on how much variation in Tb exists within populations of organisms, and whether this variation consistently differs among individuals over time (i.e. repeatability of a trait). Here, using thermal radio-frequency identification implants, we quantified the repeatability of Tb, both in the context of a fixed average environment (∼21°C) and across ambient temperatures (6-31°C), in a free-living population of tree swallows (Tachycineta bicolor, n=16). By experimentally trimming the ventral plumage of a subset of female swallows (n=8), we also asked whether the repeatability of Tb is influenced by the capacity to dissipate body heat. We found that both female and male tree swallow Tb was repeatable at 21°C (R=0.89-92), but female Tb was less repeatable than male Tb across ambient temperature (Rfemale=0.10, Rmale=0.58), which may be due to differences in parental investment. Trimmed birds had on average lower Tb than control birds (by ∼0.5°C), but the repeatability of female Tb did not differ as a function of heat dissipation capacity. This suggests that trimmed individuals adjusted their Tb to account for the effects of heat loss on Tb. Our study provides a first critical step toward understanding whether Tb is responsive to natural selection, and for predicting how animal populations will respond to climatic warming.
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Affiliation(s)
- Simon Tapper
- Environmental and Life Sciences Graduate Department, Trent University, 1600 West Bank Drive, Peterborough, ON, Canada, K9L 0G2
| | - Joseph J Nocera
- Faculty of Forestry and Environmental Management, University of New Brunswick, 28 Dineen Drive, Fredericton, NB, Canada, E3B 5A3
| | - Gary Burness
- Department of Biology, Trent University, 1600 West Bank Drive, Peterborough, ON, Canada, K9L 0G2
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12
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Rubin AM, Choi MP, Hoffman AJ, Beyl HE, Mendonça MT, Wada H. Periodic Cooling during Incubation Alters the Adrenocortical Response and Posthatch Growth in Zebra Finches. Physiol Biochem Zool 2021; 94:110-123. [PMID: 33524300 DOI: 10.1086/713023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractIn birds, incubation temperature is critically deterministic for a range of traits. When parents leave the nest to forage, developing embryos can be exposed to cooling events that represent thermal stress. To investigate the consequences of periodic cooling on offspring development and physiology, we exposed zebra finch embryos to cooling events throughout the incubation period. We then compared embryonic survival, egg mass change, incubation duration, posthatch growth, and adrenocortical response of these individuals with embryos reared at a constant optimal temperature of 37.4°C and embryos reared at a constant suboptimal temperature of 36.4°C, the mean incubation temperature of periodically cooled embryos. There were no differences in embryonic survival or egg mass change during incubation, but individuals exposed to periodic cooling had longer incubation periods than those from the 37.4°C treatment and shorter incubation periods than those from the 36.4°C treatment. Periodically cooled individuals showed slower posthatch growth in comparison with both constant-temperature treatments, but this did not impact adult body size. Treatment groups did not differ in their adrenocortical response, but embryos exposed to periodic cooling and a constant temperature of 37.4°C were able to habituate to repeated capture and restraint stress, while individuals exposed to the constant temperature of 36.4°C were not. These results point to the differential impacts of cooling events versus constant low temperatures during incubation on posthatch growth and physiology and may represent a way for parents to devote less energy toward incubation while still ensuring offspring success.
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Review: Key tweaks to the chicken's beak: the versatile use of the beak by avian species and potential approaches for improvements in poultry production. Animal 2021; 15:100119. [PMID: 33579650 DOI: 10.1016/j.animal.2020.100119] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 11/20/2022] Open
Abstract
The avian beak is a multipurpose organ playing a vital role in a variety of functions, including feeding, drinking, playing, grasping objects, mating, nesting, preening and defence against predators and parasites. With regards to poultry production, the beak is the first point of contact between the bird and feed. The beak is also manipulated to prevent unwanted behaviour such as feather pecking, toe pecking and cannibalism in poultry as well as head/neck injuries to breeder hens during mating. Thus, investigating the beak morphometry of poultry in relation to feeding and other behaviours may lead to novel insights for poultry breeding, management and feeding strategies. Beak morphometry data may be captured by advanced imaging techniques coupled with the use of geometric morphometric techniques. This emerging technology may be utilized to study the effects of beak shape on many critical management issues including heat stress, parasite management, pecking and feeding behaviour. In addition, existing literature identifies several genes related to beak development in chickens and other avian species. Use of morphometric assessments to develop phenotypic data on beak shape and detailed studies on beak-related behaviours in chickens may help in improving management and welfare of commercial poultry.
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14
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Nord A, Giroud S. Lifelong Effects of Thermal Challenges During Development in Birds and Mammals. Front Physiol 2020; 11:419. [PMID: 32523540 PMCID: PMC7261927 DOI: 10.3389/fphys.2020.00419] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/07/2020] [Indexed: 11/13/2022] Open
Abstract
Before they develop competent endothermy, mammals and birds are sensitive to fluctuating temperature. It follows that early life thermal environment can trigger changes to the ontogeny of thermoregulatory control. At the ecological level, we have incomplete knowledge of how such responses affect temperature tolerance later in life. In some cases, changes to pre- and postnatal temperature prime an organism's capacity to meet a corresponding thermal environment in adulthood. However, in other cases, developmental temperature seems to constrain temperature tolerance later in life. The timing, duration, and severity of a thermal challenge will determine whether its impact is ameliorating or constraining. However, the effects influencing the transition between these states remain poorly understood, particularly in mammals and during the postnatal period. As climate change is predicted to bring more frequent spells of extreme temperature, it is relevant to ask under which circumstances developmental thermal conditions predispose or constrain animals' capacity to deal with temperature variation. Increasingly stochastic weather also implies increasingly decoupled early- and late-life thermal environments. Hence, there is a pressing need to understand better how developmental temperature impacts thermoregulatory responses to matched and mismatched thermal challenges in subsequent life stages. Here, we summarize studies on how the thermal environment before, and shortly after, birth affects the ontogeny of thermoregulation in birds and mammals, and outline how this might carry over to temperature tolerance in adulthood. We also identify key points that need addressing to understand how effects of temperature variation during development may facilitate or constrain thermal adaptation over a lifetime.
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Affiliation(s)
- Andreas Nord
- Section for Evolutionary Ecology, Department of Biology, Lund University, Lund, Sweden
| | - Sylvain Giroud
- Research Institute of Wildlife Ecology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine Vienna, Vienna, Austria
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15
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LaBarbera K, Marsh KJ, Hayes KRR, Hammond TT. Context-dependent effects of relative temperature extremes on bill morphology in a songbird. ROYAL SOCIETY OPEN SCIENCE 2020; 7:192203. [PMID: 32431895 PMCID: PMC7211890 DOI: 10.1098/rsos.192203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/10/2020] [Indexed: 06/11/2023]
Abstract
Species increasingly face environmental extremes. Morphological responses to changes in average environmental conditions are well documented, but responses to environmental extremes remain poorly understood. We used museum specimens to investigate relationships between a thermoregulatory morphological trait, bird bill surface area (SA) and a measure of short-term relative temperature extremity (RTE), which quantifies the degree that temperature maxima or minima diverge from the 5-year norm. Using a widespread, generalist species, Junco hyemalis, we found that SA exhibited different patterns of association with RTE depending on the overall temperature regime and on precipitation. While thermoregulatory function predicts larger SA at higher RTE, we found this only when the RTE existed in an environmental context that opposed it: atypically cold minimum temperature in a warm climate, or atypically warm maximum temperature in a cool climate. When environmental context amplified the RTE, we found a negative relationship between SA and RTE. We also found that the strength of associations between SA and RTE increased with precipitation. Our results suggest that trait responses to environmental variation may qualitatively differ depending on the overall environmental context, and that environmental change that extremifies already-extreme environments may produce responses that cannot be predicted from observations in less-extreme contexts.
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Affiliation(s)
- Katie LaBarbera
- Museum of Vertebrate Zoology, Department of Integrative Biology, University of California – Berkeley, Berkeley CA 94720, USA
| | - Kyle J. Marsh
- Point Blue Conservation Science, 3820 Cypress Drive, Ste #11, Petaluma, CA 94954, USA
| | - Kia R. R. Hayes
- Museum of Vertebrate Zoology, Department of Integrative Biology, University of California – Berkeley, Berkeley CA 94720, USA
| | - Talisin T. Hammond
- Museum of Vertebrate Zoology, Department of Integrative Biology, University of California – Berkeley, Berkeley CA 94720, USA
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16
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Pavlovic G, Weston MA, Symonds MRE. Morphology and geography predict the use of heat conservation behaviours across birds. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13233] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gabrielle Pavlovic
- Centre for Integrative Ecology, School of Life and Environmental Sciences Deakin University Burwood Victoria Australia
| | - Michael A. Weston
- Centre for Integrative Ecology, School of Life and Environmental Sciences Deakin University Burwood Victoria Australia
| | - Matthew R. E. Symonds
- Centre for Integrative Ecology, School of Life and Environmental Sciences Deakin University Burwood Victoria Australia
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17
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Larson ER, Eastwood JR, Micallef S, Wehbe J, Bennett ATD, Berg ML. Nest microclimate predicts bill growth in the Adelaide rosella (Aves: Psittaculidae). Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Eliza R Larson
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Justin R Eastwood
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Sarah Micallef
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Jacinta Wehbe
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Andrew T D Bennett
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
| | - Mathew L Berg
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, Australia
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18
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Burness G, Moher D, Ben-Ezra N, Kelly RJ, Hasselquist D, Chin EH. Maternal immunization increases nestling energy expenditure, immune function, and fledging success in a passerine bird. Biol Open 2018; 7:7/4/bio028803. [PMID: 29618466 PMCID: PMC5936053 DOI: 10.1242/bio.028803] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Female birds transfer maternally derived antibodies (matAb) to their nestlings, via the egg yolk. These antibodies are thought to provide passive protection, and allow nestlings to avoid the costs associated with mounting an innate immune response. To test whether there is an energetic benefit to nestlings from receiving matAb, we challenged adult female tree swallows (Tachycineta bicolor) prior to clutch initiation with either lipopolysaccharide (LPS) or saline (Control). Following hatching, one half of each female's nestlings were immunized on day 8 post-hatch with LPS or saline, and the 4-h post-immunization nestling metabolic rate (MR) was measured. There was no difference in either LPS-reactive antibodies or total Ig levels between offspring of immunized and non-immunized mothers on day 6 or 14 post-hatch, possibly reflecting a relatively short half-life of matAbs in altricial birds. Additionally, we found no evidence that nestlings from LPS-immunized mothers could avoid the growth suppression that may result from activation of an inflammatory response. Unexpectedly, we found that control nestlings from LPS mothers had higher resting MR than control nestlings of control mothers. We attribute the increased MR to the costs associated with a general non-specific enhancement of immune function in nestlings from LPS-immunized mothers. Consistent with enhanced immune function, nestlings of immunized mothers had a more robust inflammatory response to phytohaemagglutinin and higher fledging success. Our results suggest that maternal antigen exposure pre-laying can result in increased fitness for both mothers and offspring, depending on food availability. Summary: Exposure of female birds to a simulated pathogen prior to egg laying increases the metabolic rate, immune function, and fledging success of her nestlings.
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Affiliation(s)
- Gary Burness
- Department of Biology, Trent University, Peterborough, Ontario K9L 0G2, Canada
| | - Deanna Moher
- Department of Biology, Trent University, Peterborough, Ontario K9L 0G2, Canada
| | - Noah Ben-Ezra
- Department of Biology, Trent University, Peterborough, Ontario K9L 0G2, Canada
| | - Ryan J Kelly
- Department of Biology, Trent University, Peterborough, Ontario K9L 0G2, Canada
| | | | - Eunice H Chin
- Environmental and Life Science Graduate Program, Trent University, Peterborough, Ontario K9L 0G2, Canada
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19
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Friedman NR, Harmáčková L, Economo EP, Remeš V. Smaller beaks for colder winters: Thermoregulation drives beak size evolution in Australasian songbirds. Evolution 2017; 71:2120-2129. [DOI: 10.1111/evo.13274] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 04/30/2017] [Indexed: 12/28/2022]
Affiliation(s)
- Nicholas R. Friedman
- Department of Zoology and Laboratory of Ornithology; Palacký University; Tř. 17 listopadu 50 Olomouc 77900 Czech Republic
- Okinawa Institute of Science and Technology Graduate University; 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - Lenka Harmáčková
- Department of Zoology and Laboratory of Ornithology; Palacký University; Tř. 17 listopadu 50 Olomouc 77900 Czech Republic
| | - Evan P. Economo
- Okinawa Institute of Science and Technology Graduate University; 1919-1 Tancha Onna-son 904-0495 Okinawa Japan
| | - Vladimír Remeš
- Department of Zoology and Laboratory of Ornithology; Palacký University; Tř. 17 listopadu 50 Olomouc 77900 Czech Republic
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20
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Affiliation(s)
- Julia Ryeland
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Burwood Vic. Australia
| | - Michael A. Weston
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Burwood Vic. Australia
| | - Matthew R.E. Symonds
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Burwood Vic. Australia
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21
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Gibson DJ, Sylvester EVA, Turko AJ, Tattersall GJ, Wright PA. Out of the frying pan into the air--emersion behaviour and evaporative heat loss in an amphibious mangrove fish (Kryptolebias marmoratus). Biol Lett 2016; 11:rsbl.2015.0689. [PMID: 26490418 DOI: 10.1098/rsbl.2015.0689] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Amphibious fishes often emerse (leave water) when faced with unfavourable water conditions. How amphibious fishes cope with the risks of rising water temperatures may depend, in part, on the plasticity of behavioural mechanisms such as emersion thresholds. We hypothesized that the emersion threshold is reversibly plastic and thus dependent on recent acclimation history rather than on conditions during early development. Kryptolebias marmoratus were reared for 1 year at 25 or 30°C and acclimated as adults (one week) to either 25 or 30°C before exposure to an acute increase in water temperature. The emersion threshold temperature and acute thermal tolerance were significantly increased in adult fish acclimated to 30°C, but rearing temperature had no significant effect. Using a thermal imaging camera, we also showed that emersed fish in a low humidity aerial environment (30°C) lost significantly more heat (3.3°C min(-1)) than those in a high humidity environment (1.6°C min(-1)). In the field, mean relative humidity was 84%. These results provide evidence of behavioural avoidance of high temperatures and the first quantification of evaporative cooling in an amphibious fish. Furthermore, the avoidance response was reversibly plastic, flexibility that may be important for tropical amphibious fishes under increasing pressures from climatic change.
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Affiliation(s)
- Daniel J Gibson
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Emma V A Sylvester
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Andy J Turko
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Glenn J Tattersall
- Department of Biological Sciences, Brock University, St Catharines, Ontario, Canada
| | - Patricia A Wright
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
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22
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Tattersall GJ, Arnaout B, Symonds MRE. The evolution of the avian bill as a thermoregulatory organ. Biol Rev Camb Philos Soc 2016; 92:1630-1656. [PMID: 27714923 DOI: 10.1111/brv.12299] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 08/28/2016] [Accepted: 09/01/2016] [Indexed: 11/28/2022]
Abstract
The avian bill is a textbook example of how evolution shapes morphology in response to changing environments. Bills of seed-specialist finches in particular have been the focus of intense study demonstrating how climatic fluctuations acting on food availability drive bill size and shape. The avian bill also plays an important but under-appreciated role in body temperature regulation, and therefore in energetics. Birds are endothermic and rely on numerous mechanisms for balancing internal heat production with biophysical constraints of the environment. The bill is highly vascularised and heat exchange with the environment can vary substantially, ranging from around 2% to as high as 400% of basal heat production in certain species. This heat exchange may impact how birds respond to heat stress, substitute for evaporative water loss at elevated temperatures or environments of altered water availability, or be an energetic liability at low environmental temperatures. As a result, in numerous taxa, there is evidence for a positive association between bill size and environmental temperatures, both within and among species. Therefore, bill size is both developmentally flexible and evolutionarily adaptive in response to temperature. Understanding the evolution of variation in bill size however, requires explanations of all potential mechanisms. The purpose of this review, therefore, is to promote a greater understanding of the role of temperature on shaping bill size over spatial gradients as well as developmental, seasonal, and evolutionary timescales.
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Affiliation(s)
- Glenn J Tattersall
- Department of Biological Sciences, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario, L2S 3A1, Canada
| | - Bassel Arnaout
- Department of Biological Sciences, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario, L2S 3A1, Canada.,Department of Earth Sciences, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario, L2S 3A1, Canada
| | - Matthew R E Symonds
- School of Life and Environmental Sciences, Centre for Integrative Ecology, Deakin University, 221 Burwood Highway, Burwood, 3125, Australia
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23
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Tattersall GJ, Roussel D, Voituron Y, Teulier L. Novel energy-saving strategies to multiple stressors in birds: the ultradian regulation of body temperature. Proc Biol Sci 2016; 283:20161551. [PMID: 27655770 PMCID: PMC5046907 DOI: 10.1098/rspb.2016.1551] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 08/25/2016] [Indexed: 11/12/2022] Open
Abstract
This study aimed to examine thermoregulatory responses in birds facing two commonly experienced stressors, cold and fasting. Logging devices allowing long-term and precise access to internal body temperature were placed within the gizzards of ducklings acclimated to cold (CA) (5°C) or thermoneutrality (TN) (25°C). The animals were then examined under three equal 4-day periods: ad libitum feeding, fasting and re-feeding. Through the analysis of daily as well as short-term, or ultradian, variations of body temperature, we showed that while ducklings at TN show only a modest decline in daily thermoregulatory parameters when fasted, they exhibit reduced surface temperatures from key sites of vascular heat exchange during fasting. The CA birds, on the other hand, significantly reduced their short-term variations of body temperature while increasing long-term variability when fasting. This phenomenon would allow the CA birds to reduce the energetic cost of body temperature maintenance under fasting. By analysing ultradian regulation of body temperature, we describe a means by which an endotherm appears to lower thermoregulatory costs in response to the combined stressors of cold and fasting.
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Affiliation(s)
- Glenn J Tattersall
- Department of Biological Sciences, Brock University, St Catharines, ON, Canada L2S3A1
| | - Damien Roussel
- Université de Lyon, UMR 5023 Écologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1, ENTPE, CNRS, 69622 Villeurbanne, France
| | - Yann Voituron
- Université de Lyon, UMR 5023 Écologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1, ENTPE, CNRS, 69622 Villeurbanne, France
| | - Loïc Teulier
- Université de Lyon, UMR 5023 Écologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1, ENTPE, CNRS, 69622 Villeurbanne, France
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24
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Ben-Ezra N, Burness G. Constant and Cycling Incubation Temperatures Have Long-Term Effects on the Morphology and Metabolic Rate of Japanese Quail. Physiol Biochem Zool 2016; 90:96-105. [PMID: 28051937 DOI: 10.1086/688383] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Incubation temperature can have profound effects on growth and development of embryos and young birds. However, few studies have examined the role that cycling incubation temperature may play in phenotypic variation and whether these effects persist to adulthood. We incubated Japanese quail eggs at control temperatures (37.5°C), at low temperatures (36.0°C), and under a cyclical treatment that maintained the same average temperature as the low treatment (36.0°C) with high temperatures that were the same as the control (37.5°C) and low temperatures that still allowed for development of the embryo (28.0°C). Individuals in the low treatment group were smaller in mass and size than individuals in the control group but had an increased basal metabolic rate relative to individuals in the cyclical treatment group. Temperature cycling offset the effects of low incubation temperatures on metabolic rate and embryonic development but not the effects on adult mass and size. Although Japanese quail are sexually size dimorphic, with females larger than males, we could detect no evidence of sex-specific sensitivity to suboptimal incubation temperatures. These results highlight the importance of incubation temperature and pattern as sources of morphological and physiological variation of adult birds.
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25
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van de Ven TMFN, Martin RO, Vink TJF, McKechnie AE, Cunningham SJ. Regulation of Heat Exchange across the Hornbill Beak: Functional Similarities with Toucans? PLoS One 2016; 11:e0154768. [PMID: 27192218 PMCID: PMC4871549 DOI: 10.1371/journal.pone.0154768] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 04/19/2016] [Indexed: 11/18/2022] Open
Abstract
Beaks are increasingly recognised as important contributors to avian thermoregulation. Several studies supporting Allen's rule demonstrate how beak size is under strong selection related to latitude and/or air temperature (Ta). Moreover, active regulation of heat transfer from the beak has recently been demonstrated in a toucan (Ramphastos toco, Ramphastidae), with the large beak acting as an important contributor to heat dissipation. We hypothesised that hornbills (Bucerotidae) likewise use their large beaks for non-evaporative heat dissipation, and used thermal imaging to quantify heat exchange over a range of air temperatures in eighteen desert-living Southern Yellow-billed Hornbills (Tockus leucomelas). We found that hornbills dissipate heat via the beak at air temperatures between 30.7°C and 41.4°C. The difference between beak surface and environmental temperatures abruptly increased when air temperature was within ~10°C below body temperature, indicating active regulation of heat loss. Maximum observed heat loss via the beak was 19.9% of total non-evaporative heat loss across the body surface. Heat loss per unit surface area via the beak more than doubled at Ta > 30.7°C compared to Ta < 30.7°C and at its peak dissipated 25.1 W m(-2). Maximum heat flux rate across the beak of toucans under comparable convective conditions was calculated to be as high as 61.4 W m(-2). The threshold air temperature at which toucans vasodilated their beak was lower than that of the hornbills, and thus had a larger potential for heat loss at lower air temperatures. Respiratory cooling (panting) thresholds were also lower in toucans compared to hornbills. Both beak vasodilation and panting threshold temperatures are potentially explained by differences in acclimation to environmental conditions and in the efficiency of evaporative cooling under differing environmental conditions. We speculate that non-evaporative heat dissipation may be a particularly important mechanism for animals inhabiting humid regions, such as toucans, and less critical for animals residing in more arid conditions, such as Southern Yellow-billed Hornbills. Alternatively, differences in beak morphology and hardness enforced by different diets may affect the capacity of birds to use the beak for non-evaporative heat loss.
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Affiliation(s)
- T. M. F. N. van de Ven
- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Cape Town, 7701, South Africa
- * E-mail:
| | - R. O. Martin
- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Cape Town, 7701, South Africa
| | - T. J. F. Vink
- Institute for Coastal and Marine Research, Department of Botany, Nelson Mandela Metropolitan University, Port Elizabeth, 6031, South Africa
| | - A. E. McKechnie
- DST-NRF Centre of Excellence at the Percy FitzPatrick Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa
| | - S. J. Cunningham
- Percy FitzPatrick Institute of African Ornithology, DST-NRF Centre of Excellence, University of Cape Town, Cape Town, 7701, South Africa
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26
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Cardilini APA, Buchanan KL, Sherman CDH, Cassey P, Symonds MRE. Tests of ecogeographical relationships in a non-native species: what rules avian morphology? Oecologia 2016; 181:783-93. [DOI: 10.1007/s00442-016-3590-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 02/12/2016] [Indexed: 11/24/2022]
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27
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Teulier L, Rouanet JL, Rey B, Roussel D. Ontogeny of non-shivering thermogenesis in Muscovy ducklings (Cairina moschata). Comp Biochem Physiol A Mol Integr Physiol 2014; 175:82-9. [DOI: 10.1016/j.cbpa.2014.05.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 05/09/2014] [Accepted: 05/16/2014] [Indexed: 01/09/2023]
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28
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Targeted 13C enrichment of lipid and protein pools in the body reveals circadian changes in oxidative fuel mixture during prolonged fasting: A case study using Japanese quail. Comp Biochem Physiol A Mol Integr Physiol 2013; 166:546-54. [DOI: 10.1016/j.cbpa.2013.08.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 08/15/2013] [Accepted: 08/16/2013] [Indexed: 11/21/2022]
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29
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Temperature fits the bill. Nature 2013. [DOI: 10.1038/500009d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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