1
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Beale PK, Foley WJ, Moore BD, Marsh KJ. Warmer ambient temperatures reduce protein intake by a mammalian folivore. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220543. [PMID: 37839444 PMCID: PMC10577027 DOI: 10.1098/rstb.2022.0543] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 08/21/2023] [Indexed: 10/17/2023] Open
Abstract
The interplay between ambient temperature and nutrition in wild herbivores is frequently overlooked, despite the fundamental importance of food. We tested whether different ambient temperatures (10°C, 18°C and 26°C) influenced the intake of protein by a marsupial herbivore, the common brushtail possum (Trichosurus vulpecula). At each temperature, possums were offered a choice of two foods containing different amounts of protein (57% versus 8%) for one week. Animals mixed a diet with a lower proportion of protein to non-protein (P : NP, 0.20) when held at 26°C compared to that at both 10°C and 18°C (0.22). Since detoxification of plant secondary metabolites imposes a protein cost on animals, we then studied whether addition of the monoterpene 1,8-cineole to the food changed the effect of ambient temperature (10°C and 26°C) on food choice. Cineole reduced food intake but also removed the effect of temperature on P : NP ratio and instead animals opted for a diet with higher P : NP (0.19 with cineole versus 0.15 without cineole). These experiments show the proportion of P : NP chosen by animals is influenced by ambient temperature and by plant secondary metabolites. Protein is critical for reproductive success in this species and reduced protein intake caused by high ambient temperatures may limit the viability of some populations in the future. This article is part of the theme issue 'Food processing and nutritional assimilation in animals'.
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Affiliation(s)
- Phillipa K. Beale
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - William J. Foley
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Ben D. Moore
- Hawkesbury Institute for the Environment, Western Sydney University, Locked bag 1797, Penrith, New South Wales 2751, Australia
| | - Karen J. Marsh
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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2
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Bethge J, Fietz J, Razafimampiandra JC, Ruthsatz K, Dausmann KH. Season and reproductive activity influence cortisol levels in the Malagasy primate Lepilemur edwardsi. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:994-1001. [PMID: 36123775 DOI: 10.1002/jez.2658] [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: 04/21/2022] [Revised: 07/30/2022] [Accepted: 08/29/2022] [Indexed: 06/15/2023]
Abstract
Throughout the year, wild animals are exposed to a variety of challenges such as changing environmental conditions and reproductive activity. These challenges may affect their stress hormone levels for varying durations and in varying intensities and impacts. Measurements of the glucocorticoid hormone cortisol in the hair of mammals are considered a good biomarker for measuring physiological stress and are increasingly used to evaluate stress hormone levels of wild animals. Here, we examined the influence of season, reproductive activity, sex, as well as body condition on hair cortisol concentrations (HCC) in Lepilemur edwardsi, a small Malagasy primate species. L. edwardsi lives in the seasonal dry forests of western Madagascar, which are characterized by a strongly changing resource availability throughout the year. We hypothesized that these seasonal changes of resource availability and additionally the reproductive cycle of this species would influence HCC of L. edwardsi. Results revealed that hair cortisol concentration of females did not change seasonally or with the reproductive cycle. However, we found a significant increase of hair cortisol levels in males from the early wet season during the early dry season (mating season). This increase is presumably due to changed behavior during the mating season, as sportive lemurs travel more and show aggressive behavior during this time of the year. This behavior is energy-costly and stressful, and presumably leads to elevated HCC. As elevated cortisol levels may impair immune function, L. edwardsi males might also be more susceptible to parasites and diseases, which is unfavorable in particular during a period of low resource availability (dry season).
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Affiliation(s)
- Janina Bethge
- Institute of Cell and Systems Biology of Animals, Functional Ecology, Universität Hamburg, Hamburg, Germany
| | - Joanna Fietz
- Department of Zoology, Institute of Biology, Universität Hohenheim, Stuttgart, Germany
| | - Jean Claude Razafimampiandra
- Mention Zoologie et Biodiversité Animale, Faculté des Sciences, Université d'Antananarivo, Antananarivo, Madagascar
| | - Katharina Ruthsatz
- TU Braunschweig, Zoological Institute, Evolutionsbiologie, Braunschweig, Germany
| | - Kathrin H Dausmann
- Institute of Cell and Systems Biology of Animals, Functional Ecology, Universität Hamburg, Hamburg, Germany
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3
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Mohammadi S, Yang L, Bulbert M, Rowland HM. Defence mitigation by predators of chemically defended prey integrated over the predation sequence and across biological levels with a focus on cardiotonic steroids. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220363. [PMID: 36133149 PMCID: PMC9449480 DOI: 10.1098/rsos.220363] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/17/2022] [Indexed: 05/10/2023]
Abstract
Predator-prey interactions have long served as models for the investigation of adaptation and fitness in natural environments. Anti-predator defences such as mimicry and camouflage provide some of the best examples of evolution. Predators, in turn, have evolved sensory systems, cognitive abilities and physiological resistance to prey defences. In contrast to prey defences which have been reviewed extensively, the evolution of predator counter-strategies has received less attention. To gain a comprehensive view of how prey defences can influence the evolution of predator counter-strategies, it is essential to investigate how and when selection can operate. In this review we evaluate how predators overcome prey defences during (i) encounter, (ii) detection, (iii) identification, (iv) approach, (v) subjugation, and (vi) consumption. We focus on prey that are protected by cardiotonic steroids (CTS)-defensive compounds that are found in a wide range of taxa, and that have a specific physiological target. In this system, coevolution is well characterized between specialist insect herbivores and their host plants but evidence for coevolution between CTS-defended prey and their predators has received less attention. Using the predation sequence framework, we organize 574 studies reporting predators overcoming CTS defences, integrate these counter-strategies across biological levels of organization, and discuss the costs and benefits of attacking CTS-defended prey. We show that distinct lineages of predators have evolved dissecting behaviour, changes in perception of risk and of taste perception, and target-site insensitivity. We draw attention to biochemical, hormonal and microbiological strategies that have yet to be investigated as predator counter-adaptations to CTS defences. We show that the predation sequence framework will be useful for organizing future studies of chemically mediated systems and coevolution.
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Affiliation(s)
- Shabnam Mohammadi
- School of Biological Sciences, University of Nebraska, Lincoln, NE, USA
- Institut für Zell- und Systembiologie der Tiere, Universität Hamburg, Hamburg, Germany
- Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Lu Yang
- Wellcome Sanger Institute, Cambridge, UK
| | - Matthew Bulbert
- Department of Biological Sciences, Macquarie University North Ryde, New South Wales, Australia
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, University of Oxford Brookes, Oxford, UK
- Max Planck Institute for Chemical Ecology, Jena, Germany
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4
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Mohammadi S, Yang L, Bulbert M, Rowland HM. Defence mitigation by predators of chemically defended prey integrated over the predation sequence and across biological levels with a focus on cardiotonic steroids. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220363. [PMID: 36133149 DOI: 10.6084/m9.figshare.c.6168216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/17/2022] [Indexed: 05/25/2023]
Abstract
Predator-prey interactions have long served as models for the investigation of adaptation and fitness in natural environments. Anti-predator defences such as mimicry and camouflage provide some of the best examples of evolution. Predators, in turn, have evolved sensory systems, cognitive abilities and physiological resistance to prey defences. In contrast to prey defences which have been reviewed extensively, the evolution of predator counter-strategies has received less attention. To gain a comprehensive view of how prey defences can influence the evolution of predator counter-strategies, it is essential to investigate how and when selection can operate. In this review we evaluate how predators overcome prey defences during (i) encounter, (ii) detection, (iii) identification, (iv) approach, (v) subjugation, and (vi) consumption. We focus on prey that are protected by cardiotonic steroids (CTS)-defensive compounds that are found in a wide range of taxa, and that have a specific physiological target. In this system, coevolution is well characterized between specialist insect herbivores and their host plants but evidence for coevolution between CTS-defended prey and their predators has received less attention. Using the predation sequence framework, we organize 574 studies reporting predators overcoming CTS defences, integrate these counter-strategies across biological levels of organization, and discuss the costs and benefits of attacking CTS-defended prey. We show that distinct lineages of predators have evolved dissecting behaviour, changes in perception of risk and of taste perception, and target-site insensitivity. We draw attention to biochemical, hormonal and microbiological strategies that have yet to be investigated as predator counter-adaptations to CTS defences. We show that the predation sequence framework will be useful for organizing future studies of chemically mediated systems and coevolution.
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Affiliation(s)
- Shabnam Mohammadi
- School of Biological Sciences, University of Nebraska, Lincoln, NE, USA
- Institut für Zell- und Systembiologie der Tiere, Universität Hamburg, Hamburg, Germany
- Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Lu Yang
- Wellcome Sanger Institute, Cambridge, UK
| | - Matthew Bulbert
- Department of Biological Sciences, Macquarie University North Ryde, New South Wales, Australia
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, University of Oxford Brookes, Oxford, UK
- Max Planck Institute for Chemical Ecology, Jena, Germany
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5
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Windley HR, Starrs D, Stalenberg E, Rothman JM, Ganzhorn JU, Foley WJ. Plant secondary metabolites and primate food choices: A meta-analysis and future directions. Am J Primatol 2022; 84:e23397. [PMID: 35700311 DOI: 10.1002/ajp.23397] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 05/06/2022] [Accepted: 05/11/2022] [Indexed: 11/07/2022]
Abstract
The role of plant secondary metabolites (PSMs) in shaping the feeding decisions, habitat suitability, and reproductive success of herbivorous mammals has been a major theme in ecology for decades. Although primatologists were among the first to test these ideas, studies of PSMs in the feeding ecology of non-human primates have lagged in recent years, leading to a recent call for primatologists to reconnect with phytochemists to advance our understanding of the primate nutrition. To further this case, we present a formal meta-analysis of diet choice in response to PSMs based on field studies on wild primates. Our analysis of 155 measurements of primate feeding response to PSMs is drawn from 53 studies across 43 primate species which focussed primarily on the effect of three classes of PSMs tannins, phenolics, and alkaloids. We found a small but significant effect of PSMs on the diet choice of wild primates, which was largely driven by the finding that colobine primates showed a moderate aversion to condensed tannins. Conversely, there was no evidence that PSMs had a significant deterrent effect on food choices of non-colobine primates when all were combined into a single group. Furthermore, within the colobine primates, no other PSMs influenced feeding choices and we found no evidence that foregut anatomy significantly affected food choice with respect to PSMs. We suggest that methodological improvements related to experimental approaches and the adoption of new techniques including metabolomics are needed to advance our understanding of primate diet choice.
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Affiliation(s)
- Hannah R Windley
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia.,Wildlife Ecology Laboratory, Department of Wildlife Biology, Forestry and Forest Products Research Institute, Tsukuba, Ibaraki, Japan
| | - Danswell Starrs
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Eleanor Stalenberg
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia.,Hawkesbury Institute of the Environment, Western Sydney University, Richmond, New South Wales, Australia
| | - Jessica M Rothman
- Department of Anthropology, Hunter College of the City University of New York, and New York Consortium in Evolutionary Primatology, New York, New York, USA
| | - Joerg U Ganzhorn
- Animal Ecology and Conservation, Universität Hamburg, Hamburg, Germany
| | - William J Foley
- Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia.,Animal Ecology and Conservation, Universität Hamburg, Hamburg, Germany
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6
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Beale PK, Connors PK, Dearing MD, Moore BD, Krockenberger AK, Foley WJ, Marsh KJ. Warmer Ambient Temperatures Depress Detoxification and Food Intake by Marsupial Folivores. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.888550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ambient temperature is an underappreciated determinant of foraging behaviour in wild endotherms, and the requirement to thermoregulate likely influences food intake through multiple interacting mechanisms. We investigated relationships between ambient temperature and hepatic detoxification capacity in two herbivorous marsupials, the common ringtail possum (Pseudocheirus peregrinus) and common brushtail possum (Trichosurus vulpecula) that regularly feed on diets rich in plant toxins. As an indicator of hepatic detoxification capacity, we determined the functional clearance rate of an anaesthetic agent, Alfaxalone, after possums were acclimated to 10°C [below the thermoneutral zone (TNZ)], 18°C [approximately lower critical temperature (LCT)], and 26°C [approximately upper critical temperature (UCT)] for either 7 days or less than 24 h. We then measured intake of foods with high or low plant secondary metabolite (PSM) concentrations under the same temperature regimes. After 7 days of acclimation, we found a positive correlation between the functional clearance rate of Alfaxalone and ambient temperature, and a negative relationship between ambient temperature and intake of foods with high or low PSM concentrations for both species. The effect of ambient temperature on intake of diets rich in PSMs was absent or reduced when possums were kept at temperatures for less than 24 h. Our results underscore the effects of ambient temperature in hepatic metabolism particularly with respect intake of diets containing PSMs. Given that the planet is warming, it is vital that effects of ambient temperature on metabolism, nutrition and foraging by mammalian herbivores is taken into account to predict range changes of species and their impact on ecosystems.
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7
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Bethge J, Razafimampiandra JC, Wulff A, Dausmann KH. Seasonal changes in the parasite prevalence of a small Malagasy lemur species (Lepilemur edwardsi). Integr Zool 2022; 18:427-439. [PMID: 35276032 DOI: 10.1111/1749-4877.12647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Parasitic infections can impact the fitness of individuals and can have influence on animals' population dynamics. An individuals' parasite prevalence often changes depending on external or seasonal changes, e.g., rainfall and ambient temperatures, but also on internal changes, e.g., changes in body condition. In this study we aimed to identify the environmental factors that may influence the intestinal parasite and ectoparasite prevalence of the folivorous Malagasy primate species, Lepilemur edwardsi, living in a seasonal dry deciduous forest. Species living in this habitat have to adapt to seasonal changes of ambient temperature, with almost no precipitation during the dry season and hence strong fluctuations of resource availability throughout the year. We sampled the feces and ectoparasites of L. edwardsi throughout the year. Intestinal parasite prevalence increased from the wet to the dry season and was highest in the late dry season, which might be due to the accompanying decrease in diet-quality. Conversely, ectoparasite prevalence decreased in the dry season, presumably due to the prevailing unfavorable environmental conditions for the development of ectoparasites (i.e., mites and ticks). Paired with the higher resting metabolism and stress level of L. edwardsi during the late dry season, it seems that this species may struggle when dry seasons intensify in its habitat. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Janina Bethge
- Institute of Zoology, Functional Ecology, Universität Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
| | - Jean Claude Razafimampiandra
- Mention Zoologie et Biodiversité Animale, Faculté des Sciences, Université d'Antananarivo, B.P. 906, 101, Antananarivo, Madagascar
| | - Arne Wulff
- Institute of Zoology, Functional Ecology, Universität Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
| | - Kathrin H Dausmann
- Institute of Zoology, Functional Ecology, Universität Hamburg, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany
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8
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Chen S, Holyoak M, Liu H, Bao H, Ma Y, Dou H, Jiang G. Effects of spatially heterogeneous warming on gut microbiota, nutrition and gene flow of a heat-sensitive ungulate population. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150537. [PMID: 34844317 DOI: 10.1016/j.scitotenv.2021.150537] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 09/19/2021] [Accepted: 09/19/2021] [Indexed: 06/13/2023]
Abstract
Effects of climate warming on trophic cascades are increasingly reported for large herbivores occupying northern latitudes. During the last 40 years, moose (Alces alces) in northeast China have lost nearly half of their historical distribution through their habitat shifting northwards. There are many possible causes of bottom-up and top-down effects of temperature and for moose in northeast China they are poorly understood. Of particular relevance are the effects of extrinsic environmental factors on gene flow, nutritional adaptions, and gut microbiota that occur as moose populations retreat northwards. We combined molecular biology, nutritional ecology and metagenomics to gain deeper mechanistic insights into the effects of temperature on moose populations. In this study, we revealed that the direction and intensity of gene flow is consistent with global warming driving retreats of moose populations. We interpret this as evidence for the northward movement of moose populations, with cooler northern populations receiving more immigrants and warmer southern populations supplying emigrants. Comparison across latitudes showed that warmer late spring temperatures were associated with plant community composition and facilitated related changes in moose protein and carbohydrate intake through altering forage availability, forage quality and diet composition. Furthermore, these nutrient shifts were accompanied by changes in gut microbial composition and functional pathways related to nutrient metabolism. This study provided insights into mechanisms driving effects of spatial heterogeneous warming on genetic, nutritional and physiological adaptions related to key demographic rates and patterns of survival of heat-sensitive ungulates along a latitude gradient. Understanding such changes helps to identify key habitat areas and plant species to ensure accurate assessment of population status and targeted management of moose populations.
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Affiliation(s)
- Shiyu Chen
- Feline Research Center of National Forestry and Grassland Administration, College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Marcel Holyoak
- Department of Environmental Science and Policy, University of California, Davis, CA 95616, USA
| | - Hui Liu
- Feline Research Center of National Forestry and Grassland Administration, College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China; College of Forestry, Hainan University, Haikou 570228, China
| | - Heng Bao
- Feline Research Center of National Forestry and Grassland Administration, College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Yingjie Ma
- Feline Research Center of National Forestry and Grassland Administration, College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China; Key Lab of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 1-5 Beichenxi Road, Chaoyang, Beijing 100101, China
| | - Hongliang Dou
- Feline Research Center of National Forestry and Grassland Administration, College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China; Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization, Guangdong Academy of Forestry, Guangzhou 510520, China
| | - Guangshun Jiang
- Feline Research Center of National Forestry and Grassland Administration, College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China.
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9
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Bethge J, Razafimampiandra JC, Wulff A, Dausmann KH. Sportive lemurs elevate their metabolic rate during challenging seasons and do not enter regular heterothermy. CONSERVATION PHYSIOLOGY 2021; 9:coab075. [PMID: 34527247 PMCID: PMC8436000 DOI: 10.1093/conphys/coab075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/30/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
Animals experience seasonal changes of environmental and ecological conditions in most habitats. Fluctuations in ambient temperature have a strong influence on thermoregulation, particularly on small endothermic mammals. However, different mammalian species cope differently with these changes. Understanding the physiological responses of organisms to different seasons and analysing the mechanisms that account for intra- and inter-specific differences and the ecological consequences of these variations is important to predict species responses to climatic changes. Consequences of climatic changes will be most pronounced in climatically already challenging habitats, such as the dry regions of western Madagascar. We aimed to identify the seasonal responses and adaptive possibilities in energy budgeting of Lepilemur edwardsi, a small primate of this habitat, by measuring metabolic rate (MR; open-flow respiratory) and skin temperature in the field during different seasons. Resting metabolism was generally low, but our study did not detect any signs of regular heterothermic episodes, despite the fact that these are known in other sympatrically living lemurs with a similar lifestyle. Surprisingly, L. edwardsi responded by elevating its resting MR in the poor-resourced dry season, compared to the better-resourced wet season, presumably to master detoxification of their increasingly toxic diet. As body mass decreased over this time, this strategy is obviously not energetically balanced on the long term. This is cause for concern, as it suggests that L. edwardsi has a very small leeway to adjust to changing conditions as experienced due to climate change, as dry season are expected to become longer and hotter, straining water budgets and food quality even more. Moreover, our findings highlight the importance of studying physiological parameters directly in the field and under differing climatic conditions.
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Affiliation(s)
- Janina Bethge
- Functional Ecology, Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
| | - Jean Claude Razafimampiandra
- Mention Zoologie et Biodiversité Animale, Faculté des Sciences, Université d’Antananarivo, B.P. 906, 101 Antananarivo, Madagascar
| | - Arne Wulff
- Functional Ecology, Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
| | - Kathrin H Dausmann
- Functional Ecology, Institute of Zoology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
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10
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Godde C, Mason-D’Croz D, Mayberry D, Thornton P, Herrero M. Impacts of climate change on the livestock food supply chain; a review of the evidence. GLOBAL FOOD SECURITY-AGRICULTURE POLICY ECONOMICS AND ENVIRONMENT 2021; 28:100488. [PMID: 33738188 PMCID: PMC7938222 DOI: 10.1016/j.gfs.2020.100488] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 12/23/2022]
Abstract
The potential impacts of climate change on current livestock systems worldwide are a major concern, and yet the topic is covered to a limited extent in global reports such as the ones produced by the Intergovernmental Panel on Climate Change. In this article, we review the risk of climate-related impacts along the land-based livestock food supply chain. Although a quantification of the net impacts of climate change on the livestock sector is beyond the reach of our current understanding, there is strong evidence that there will be impacts throughout the supply chain, from farm production to processing operations, storage, transport, retailing and human consumption. The risks of climate-related impacts are highly context-specific but expected to be higher in environments that are already hot and have limited socio-economic and institutional resources for adaptation. Large uncertainties remain as to climate futures and the exposure and responses of the interlinked human and natural systems to climatic changes over time. Consequently, adaptation choices will need to account for a wide range of possible futures, including those with low probability but large consequences. Risk results from the interaction of climate-related hazards with the exposure and vulnerability of human and natural systems. Climate change will impact the livestock sector throughout the food supply chain—from farm production to human consumption. Key hazards relate to climate change trends but also, and importantly, to climate variability and climate extremes. Large uncertainties remain as to climate futures and the exposure and responses of the interlinked human and natural systems. Adaptation choices will need to account for a wide range of possible futures.
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Affiliation(s)
- C.M. Godde
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, St Lucia, QLD, 4067, Australia
- Corresponding author.
| | - D. Mason-D’Croz
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, St Lucia, QLD, 4067, Australia
| | - D.E. Mayberry
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, St Lucia, QLD, 4067, Australia
| | - P.K. Thornton
- CGIAR Research Programme on Climate Change, Agriculture and Food Security (CCAFS), ILRI, Nairobi, Kenya
| | - M. Herrero
- Commonwealth Scientific and Industrial Research Organisation, Agriculture and Food, St Lucia, QLD, 4067, Australia
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11
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Windley HR, Shimada T. Cold temperature improves tannin tolerance in a granivorous rodent. J Anim Ecol 2019; 89:471-481. [PMID: 31580494 DOI: 10.1111/1365-2656.13119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 09/18/2019] [Indexed: 11/28/2022]
Abstract
The foraging ecology of mammalian herbivores is regulated in part by their ability to detoxify plant secondary metabolites (PSM). Ambient temperature has been shown to alter liver function in rodents and the toxicity of some PSMs, but little is known about the physiological and nutritional consequences of consuming PSMs at different ambient temperatures. Furthermore, the effect of ambient temperature on the response of mammals to the most ubiquitous class of PSM, tannins, is unknown. We measured the effect of temperature and tannin intake on liver function, and the subsequent effect on the tannin tolerance of wild Japanese wood mice, Apodemus speciosus. The experiment involved acclimation to one of two ambient temperatures (10°C or 20°C) followed by acclimation to a diet of acorns (6.2% tannin DW). Liver function was measured both before and after acclimation to acorns by measuring the clearance time of a hypnotic agent. Finally, the mice were fed only acorns in a 5-day feeding experiment to assess their tolerance to tannin in the diet. Acclimation to acorns had a significant effect on liver function, but the direction of this effect was dependent on ambient temperature. Acorn consumption improved the liver function of wood mice at 10°C, but reduced liver function at 20°C, revealing a complex relationship between ambient temperature and tannin intake on liver function. Furthermore, mice with better liver function, indicated by faster clearance of the hypnotic agent, exhibited higher protein digestibility on an acorn-only diet, indicative of higher tannin tolerance. These results suggest that environmental temperature plays a significant role in the tolerance of A. speciosus to tannins, providing new insight into their seasonal feeding behaviour and winter ecology. We contend that cold-induced tannin tolerance may help to explain the population dynamics of mammalian herbivores with seasonal changes in the tannin content of their diet, and inform predictions about the response of these animals to a changing climate.
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Affiliation(s)
- Hannah R Windley
- Wildlife Ecology Laboratory, Department of Wildlife Biology, Forestry and Forest Products Research Institute, Tsukuba, Japan
| | - Takuya Shimada
- Wildlife Ecology Laboratory, Department of Wildlife Biology, Forestry and Forest Products Research Institute, Tsukuba, Japan
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12
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Villalba JJ, Manteca X. A Case for Eustress in Grazing Animals. Front Vet Sci 2019; 6:303. [PMID: 31572737 PMCID: PMC6753217 DOI: 10.3389/fvets.2019.00303] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 08/27/2019] [Indexed: 12/30/2022] Open
Abstract
Herbivores grazing in extensive systems are exposed to a series of challenges, rooted in the inherent spatial and temporal variability of their environment that potentially constrain their health, nutrition, and welfare. Nevertheless, in this review, we argue that challenges induced by some biotic (e.g., vegetation) and abiotic (e.g., terrain) factors may also be viewed as "positive" sources of stress or eustress, since they present complex problems, that when solved successfully elicit a greater degree of behavioral plasticity and adaptability in grazing animals. Chemically and structurally diverse landscapes require animals to display complex behaviors and exhibit adaptive capabilities, like building a balanced and safe diet or finding shelter, which ultimately lead to positive emotional states. Thus, maintaining or enhancing the diversity occurring in natural systems represent a management approach that can be used to improve welfare and prepare the animal for an efficient adaptation to future, and potentially unknown, environmental challenges.
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Affiliation(s)
- Juan J. Villalba
- Department of Wildland Resources, Utah State University, Logan, UT, United States
| | - Xavier Manteca
- School of Veterinary Science, Universidad Autónoma de Barcelona, Barcelona, Spain
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13
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Tietje WD, Polyakov AY, Rolland V, Hines JE, Oli MK. Climatic influences on demography of the California mouse (Peromyscus californicus) in semiarid oak woodland. J Mammal 2018. [DOI: 10.1093/jmammal/gyy089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- William D Tietje
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, USA
| | - Anne Y Polyakov
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, USA
| | - Virginie Rolland
- Department of Biological Sciences, Arkansas State University, Jonesboro, AR, USA
| | - James E Hines
- United States Geological Survey, Patuxent Wildlife Research Center, Laurel, MD, USA
| | - Madan K Oli
- Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, FL, USA
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14
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Review: Using physiologically based models to predict population responses to phytochemicals by wild vertebrate herbivores. Animal 2018; 12:s383-s398. [PMID: 30251623 DOI: 10.1017/s1751731118002264] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
To understand how foraging decisions impact individual fitness of herbivores, nutritional ecologists must consider the complex in vivo dynamics of nutrient-nutrient interactions and nutrient-toxin interactions associated with foraging. Mathematical modeling has long been used to make foraging predictions (e.g. optimal foraging theory) but has largely been restricted to a single currency (e.g. energy) or using simple indices of nutrition (e.g. fecal nitrogen) without full consideration of physiologically based interactions among numerous co-ingested phytochemicals. Here, we describe a physiologically based model (PBM) that provides a mechanistic link between foraging decisions and demographic consequences. Including physiological mechanisms of absorption, digestion and metabolism of phytochemicals in PBMs allows us to estimate concentrations of ingested and interacting phytochemicals in the body. Estimated phytochemical concentrations more accurately link intake of phytochemicals to changes in individual fitness than measures of intake alone. Further, we illustrate how estimated physiological parameters can be integrated with the geometric framework of nutrition and into integral projection models and agent-based models to predict fitness and population responses of vertebrate herbivores to ingested phytochemicals. The PBMs will improve our ability to understand the foraging decisions of vertebrate herbivores and consequences of those decisions and may help identify key physiological mechanisms that underlie diet-based ecological adaptations.
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15
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Hall LE, Chalfoun AD. What to eat in a warming world: do increased temperatures necessitate hazardous duty pay? Oecologia 2017; 186:73-84. [DOI: 10.1007/s00442-017-3993-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 10/24/2017] [Indexed: 10/18/2022]
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16
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Beale PK, Marsh KJ, Foley WJ, Moore BD. A hot lunch for herbivores: physiological effects of elevated temperatures on mammalian feeding ecology. Biol Rev Camb Philos Soc 2017; 93:674-692. [DOI: 10.1111/brv.12364] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/25/2017] [Accepted: 08/09/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Phillipa K. Beale
- Research School of Biology The Australian National University Canberra Australian Capital Territory 2601 Australia
| | - Karen J. Marsh
- Research School of Biology The Australian National University Canberra Australian Capital Territory 2601 Australia
| | - William J. Foley
- Research School of Biology The Australian National University Canberra Australian Capital Territory 2601 Australia
- Animal Ecology and Conservation University of Hamburg, Martin‐Luther‐King‐Platz 3 20146 Hamburg Germany
| | - Ben D. Moore
- Hawkesbury Institute for the Environment Western Sydney University, Locked bag 1797 Penrith New South Wales 2751 Australia
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17
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Ditmer MA, Moen RA, Windels SK, Forester JD, Ness TE, Harris TR. Moose at their bioclimatic edge alter their behavior based on weather, landscape, and predators. Curr Zool 2017; 64:419-432. [PMID: 30109872 PMCID: PMC6084617 DOI: 10.1093/cz/zox047] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 07/17/2017] [Indexed: 11/23/2022] Open
Abstract
Populations inhabiting the bioclimatic edges of a species’ geographic range face an increasing amount of stress from alterations to their environment associated with climate change. Moose Alces alces are large-bodied ungulates that are sensitive to heat stress and have exhibited population declines and range contractions along their southern geographic extent. Using a hidden Markov model to analyze movement and accelerometer data, we assigned behaviors (rest, forage, or travel) to all locations of global positioning system-collared moose (n = 13, moose-years = 19) living near the southern edge of the species’ range in and around Voyageurs National Park, MN, USA. We assessed how moose behavior changed relative to weather, landscape, and the presence of predators. Moose significantly reduced travel and increased resting behaviors at ambient temperatures as low as 15 °C and 24 °C during the spring and summer, respectively. In general, moose behavior changed seasonally in association with distance to lakes and ponds. Moose used wetlands for travel throughout the year, rested in conifer forests, and foraged in shrublands. The influence of wolves Canis lupus varied among individual moose and season, but the largest influence was a reduction in travel during spring when near a wolf home range core, primarily by pregnant females. Our analysis goes beyond habitat selection to capture how moose alter their activities based on their environment. Our findings, along with climate change forecasts, suggest that moose in this area will be required to further alter their activity patterns and space use in order to find sufficient forage and avoid heat stress.
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Affiliation(s)
- Mark A Ditmer
- Conservation Department, Minnesota Zoo, 13000 Zoo Boulevard, Apple Valley, MN, USA.,Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, Ste 135, St Paul, MN, USA
| | - Ron A Moen
- Natural Resources Research Institute and Department of Biology, University of Minnesota Duluth, 5013 Miller Trunk Highway, Duluth, MN, USA
| | - Steve K Windels
- Voyageurs National Park, 360 Hwy 11 E, International Falls, MN, USA
| | - James D Forester
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, Ste 135, St Paul, MN, USA
| | - Thomas E Ness
- Conservation Department, Minnesota Zoo, 13000 Zoo Boulevard, Apple Valley, MN, USA
| | - Tara R Harris
- Conservation Department, Minnesota Zoo, 13000 Zoo Boulevard, Apple Valley, MN, USA.,Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, Ste 135, St Paul, MN, USA
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18
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Connors PK, Malenke JR, Dearing MD. Ambient temperature‐mediated changes in hepatic gene expression of a mammalian herbivore (
Neotoma lepida
). Mol Ecol 2017; 26:4322-4338. [DOI: 10.1111/mec.14192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/03/2017] [Accepted: 05/15/2017] [Indexed: 02/04/2023]
Affiliation(s)
| | - Jael R. Malenke
- Department of Biology University of Utah Salt Lake City UT USA
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19
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Bethge J, Wist B, Stalenberg E, Dausmann K. Seasonal adaptations in energy budgeting in the primate Lepilemur leucopus. J Comp Physiol B 2017; 187:827-834. [PMID: 28314947 DOI: 10.1007/s00360-017-1082-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 12/03/2016] [Accepted: 02/26/2017] [Indexed: 11/25/2022]
Abstract
The spiny forest of South Madagascar is one of the driest and most unpredictable habitats in Africa. The small-bodied, nocturnal primate Lepilemur leucopus lives in this harsh habitat with high diurnal and seasonal changes in ambient temperature. In this study, we investigated seasonal adaptions in energy budgeting of L. leucopus, which allow it to live under these conditions by measuring resting metabolic rate using open-flow respirometry. No signs of heterothermy were detected, and resting metabolic rate was significantly lower in the warmer wet season than in the colder dry season. In fact, L. leucopus possesses one of the lowest mass-specific metabolic rates measured so far for an endotherm, probably the result of adaptations to its habitat and folivorous and potentially toxic diet. Surprisingly, we identified a shift of the thermoneutral zone from between 25 and 30 °C in the wet season to between 29 and 32 °C in the cool dry season. L. leucopus seems to be more affected by the hot daytime temperatures during the dry season and thermoregulation seems to be more costly during this time, which makes this shift of the thermoneutral zone advantageous. Our findings suggest that L. leucopus has a very small scope to unfavorable conditions, making it highly vulnerable, e.g., to changing conditions due to climate change.
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Affiliation(s)
- Janina Bethge
- Zoological Institute, Functional Ecology, Biocenter Grindel, University Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany.
| | - Bianca Wist
- Zoological Institute, Functional Ecology, Biocenter Grindel, University Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Eleanor Stalenberg
- Division of Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Kathrin Dausmann
- Zoological Institute, Functional Ecology, Biocenter Grindel, University Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
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20
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McLennan SR, Blaney BJ, Doogan VJ, Downing JA. The tolerance of steers (Bos taurus) to sorghum ergot (Claviceps africana) in a feedlot during the cooler months in subtropical Queensland. ANIMAL PRODUCTION SCIENCE 2017. [DOI: 10.1071/an15485] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Two experiments tested the tolerance of steers (Bos taurus) to sorghum ergot (Claviceps africana) during cooler months in south-east Queensland. Sorghum grain containing 2.8% ergot and 28 mg/kg ergot alkaloids (84% dihydroergosine, 10% dihydroelymoclavine, 6% festuclavine) was incorporated into feedlot rations. In a previous study in summer–autumn, ergot (1.1–4.4 mg alkaloids/kg ration) severely reduced performance in steers when the temperature–humidity index (THI; dry bulb temperature °C + 0.36 dew-point temperature °C + 41.2) was ~70, whereas a THI of ~79 was tolerated by steers fed ergot-free rations. Experiment 1 was conducted in winter–spring, with rations containing 0, 2.8, 5.6, 8.2 or 11.2 mg ergot alkaloids/kg ration. All ergot inclusions depressed feed intake (14% average reduction) and growth rate (34% average reduction), even when the weekly average daily THI was less than 65. Rectal temperatures were occasionally elevated in ergot-fed steers (P < 0.05), primarily when the THI exceeded ~65. All ergot inclusions depressed plasma prolactin concentrations in steers. Experiment 2 was predominantly carried out in winter, with weekly average daily THI <65 throughout the experiment. Rations containing 0, 0.28, 0.55 or 1.1 mg ergot alkaloids/kg were fed for 4 weeks but produced no significant effect on feed intakes and growth rates of steers. Alkaloid concentrations were then changed to 0, 2.1, 4.3 and 1.1 mg/kg, respectively. Subsequently, feed intakes declined by 17.5% (P < 0.05), and growth rates by 28% (P > 0.05) in the group receiving 4.3 mg/kg alkaloid, compared with Controls. Plasma prolactin concentrations were depressed, relative to the Controls, by dietary alkaloid inclusion greater than 1.1 mg/kg, with alkaloid intake of 4.3 mg/kg causing the greatest reduction (P < 0.05). Cattle performance in these studies shows steers can tolerate up to ~2 mg ergot alkaloid/kg (0.2% ergot) in feedlot rations under low THI conditions (< ~60–65), but previous findings indicate a much lower threshold will apply at higher THI (>65).
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21
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Abstract
Changes in atmosphere and temperature are affecting multiple environmental indicators from extreme heat events to global air quality. Workers will be uniquely affected by climate change, and the occupational impacts of major shifts in atmospheric and weather conditions need greater attention. Climate change-related exposures most likely to differentially affect workers in the USA and globally include heat, ozone, polycyclic aromatic hydrocarbons, other chemicals, pathogenic microorganisms, vector-borne diseases, violence, and wildfires. Epidemiologic evidence documents a U-, J-, or V-shaped relationship between temperature and mortality. Whereas heat-related morbidity and mortality risks are most evident in agriculture, many other outdoor occupational sectors are also at risk, including construction, transportation, landscaping, firefighting, and other emergency response operations. The toxicity of chemicals change under hyperthermic conditions, particularly for pesticides and ozone. Combined with climate-related changes in chemical transport and distribution, these interactions represent unique health risks specifically to workers. Links between heat and interpersonal conflict including violence require attention because they pose threats to the safety of emergency medicine, peacekeeping and humanitarian relief, and public safety professionals. Recommendations for anticipating how US workers will be most susceptible to climate change include formal monitoring systems for agricultural workers; modeling scenarios focusing on occupational impacts of extreme climate events including floods, wildfires, and chemical spills; and national research agenda setting focusing on control and mitigation of occupational susceptibility to climate change.
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22
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Kurnath P, Merz ND, Dearing MD. Ambient temperature influences tolerance to plant secondary compounds in a mammalian herbivore. Proc Biol Sci 2016; 283:20152387. [PMID: 26763703 PMCID: PMC4721095 DOI: 10.1098/rspb.2015.2387] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/07/2015] [Indexed: 11/12/2022] Open
Abstract
Growing evidence suggests that plant secondary compounds (PSCs) ingested by mammals become more toxic at elevated ambient temperatures, a phenomenon known as temperature-dependent toxicity. We investigated temperature-dependent toxicity in the desert woodrat (Neotoma lepida), a herbivorous rodent that naturally encounters PSCs in creosote bush (Larrea tridentata), which is a major component of its diet. First, we determined the maximum dose of creosote resin ingested by woodrats at warm (28-29°C) or cool (21-22°C) temperatures. Second, we controlled the daily dose of creosote resin ingested at warm, cool and room (25°C) temperatures, and measured persistence in feeding trials. At the warm temperature, woodrats ingested significantly less creosote resin; their maximum dose was two-thirds that of animals at the cool temperature. Moreover, woodrats at warm and room temperatures could not persist on the same dose of creosote resin as woodrats at the cool temperature. Our findings demonstrate that warmer temperatures reduce PSC intake and tolerance in herbivorous rodents, highlighting the potentially adverse consequences of temperature-dependent toxicity. These results will advance the field of herbivore ecology and may hone predictions of mammalian responses to climate change.
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Affiliation(s)
- P Kurnath
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA
| | - N D Merz
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA
| | - M D Dearing
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA
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23
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Skopec MM, Kohl KD, Schramm K, Halpert JR, Dearing MD. Using the Specialization Framework to Determine Degree of Dietary Specialization in a Herbivorous Woodrat. J Chem Ecol 2015; 41:1059-68. [PMID: 26631406 DOI: 10.1007/s10886-015-0654-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 11/09/2015] [Accepted: 11/19/2015] [Indexed: 12/26/2022]
Abstract
To be considered a dietary specialist, mammalian herbivores must consume large quantities of a plant species considered "difficult" with respect to nutrient or toxin content, and possess specialized adaptations to deal with plant defensive compounds or low nutritional content. Populations of Neotoma lepida in the Great Basin consume Juniperus osteosperma, a plant heavily defended by terpenes, but a detailed dietary analysis of this population is lacking. Therefore, we investigated the extent of dietary specialization in this species in comparison with the better-studied specialist species, N. stephensi. Microhistological analysis of feces from N. lepida revealed that greater than 90% of their diet in nature was comprised of juniper. In laboratory tolerance trials, N. lepida tolerated a diet of 80% J. osteosperma, similar to that observed for N. stephensi. There was no difference in the abilities of N. lepida and N. stephensi to metabolize hexobarbital, a proxy compound for terpene metabolism. In preference tests of native and non-native juniper species, N. lepida did not exhibit a preference for its native or co-occurring juniper, J. osteosperma, over the non-native species, J. monosperma, whereas N. stephensi preferred its native or co-occurring juniper J. monosperma over non-native J. osteosperma. Behavioral and habitat differences between these woodrat species lead to the categorization of N. stephensi as an obligate juniper specialist with a small range that overlaps that of its preferred food, J. monosperma, and N. lepida as a facultative juniper specialist with a large range, and only a portion of its distribution containing populations that feed extensively on J. osteosperma.
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Affiliation(s)
- Michele M Skopec
- Department of Zoology, Weber State University, 1415 Edvalson Dr., Ogden, UT, 84408, USA.
| | - Kevin D Kohl
- Department of Biology, University of Utah, Salt Lake City, 84112, UT, USA
| | - Katharina Schramm
- Department of Zoology, Weber State University, 1415 Edvalson Dr., Ogden, UT, 84408, USA
- Department of Biology, University of Utah, Salt Lake City, 84112, UT, USA
| | - James R Halpert
- School of Pharmacy, University of Connecticut, Storrs, CT, USA
| | - M Denise Dearing
- Department of Biology, University of Utah, Salt Lake City, 84112, UT, USA
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24
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Moore BD, Wiggins NL, Marsh KJ, Dearing MD, Foley WJ. Translating physiological signals to changes in feeding behaviour in mammals and the future effects of global climate change. ANIMAL PRODUCTION SCIENCE 2015. [DOI: 10.1071/an14487] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Mammals cannot avoid ingesting secondary metabolites, often in significant amounts. Thus, their intake must be regulated to avoid intoxication. Three broad mechanisms have been described by which this can be achieved. These are conditioned aversions mediated by nausea, non-conditioned aversions and the recognition of limits to detoxification. Although there is some overlap between these, we know little about the way that mechanisms of toxin avoidance interact with regulation of nutrient intake and whether one has priority over the other. Nonetheless, regulation of meal length and inter-meal length allows the intake of some plant secondary metabolites to be matched with an animal’s capacity for detoxification and its nutritional requirements. Toxicity itself is not a fixed limitation and recent work suggests that ambient temperature can be a major determinant of the toxicity of plant secondary metabolites, largely through effects on liver function. These effects are likely to be of major importance in predicting the impact of global climate change on herbivores.
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25
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Kohl KD, Weiss RB, Cox J, Dale C, Denise Dearing M. Gut microbes of mammalian herbivores facilitate intake of plant toxins. Ecol Lett 2014; 17:1238-46. [DOI: 10.1111/ele.12329] [Citation(s) in RCA: 186] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 04/14/2014] [Accepted: 06/18/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Kevin D. Kohl
- Department of Biology University of Utah 257 S. 1400 East Salt Lake City UT 84112 USA
| | - Robert B. Weiss
- Department of Human Genetics University of Utah 15 North 2030 East Salt Lake City UT 84112 USA
| | - James Cox
- Department of Biochemistry and the Metabolomics Core Research Facility University of Utah School of Medicine 20 South 2030 East Salt Lake City UT 84112 USA
| | - Colin Dale
- Department of Biology University of Utah 257 S. 1400 East Salt Lake City UT 84112 USA
| | - M. Denise Dearing
- Department of Biology University of Utah 257 S. 1400 East Salt Lake City UT 84112 USA
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26
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Xie JX, Lin GH, Zhang TZ, Su JP. Foraging Strategy of Plateau Zokors ( Eospalax baileyiThomas) When Collecting Food for Winter Caches. POLISH JOURNAL OF ECOLOGY 2014. [DOI: 10.3161/104.062.0116] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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27
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Forbey JS, Wiggins NL, Frye GG, Connelly JW. Hungry grouse in a warming world: emerging risks from plant chemical defenses and climate change. WILDLIFE BIOLOGY 2013. [DOI: 10.2981/13-014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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28
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Feeding rates of a mammalian browser confirm the predictions of a 'foodscape' model of its habitat. Oecologia 2013; 174:873-82. [PMID: 24253506 DOI: 10.1007/s00442-013-2808-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 10/11/2013] [Indexed: 10/26/2022]
Abstract
Adequate nutrition is a fundamental requirement for the maintenance and growth of populations, but complex interactions between nutrients and plant toxins make it difficult to link variation in plant quality to the ecology of wild herbivores. We asked whether a 'foodscape' model of habitat that uses near-infrared spectroscopy to describe the palatability of individual trees in the landscape, predicted the foraging decisions of a mammalian browser, the koala (Phascolarctos cinereus). Specifically, we considered four behavioural decision points at which nutritional quality may influence an animal's decision. These were: which tree to enter, whether to feed from that tree, when to stop eating, and how long to remain in that tree. There were trends for koalas to feed in eucalypt trees that were more palatable than unvisited neighbouring conspecific trees, and than trees that they visited but did not eat. Koalas ate longer meals in more palatable trees, and stayed longer and spent more time feeding per visit to these trees. Using more traditional chemical analyses, we identified that an interaction between the concentrations of formylated phloroglucinol compounds (a group of plant secondary metabolites) and available N (an integrated measure of tannins, digestibility and N) influenced feeding. The study shows that foodscape models that combine spatial information with integrated measures of food quality are a powerful tool to predict the feeding behaviour of herbivores in a landscape.
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29
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Kurnath P, Dearing MD. Warmer ambient temperatures depress liver function in a mammalian herbivore. Biol Lett 2013; 9:20130562. [PMID: 24046878 DOI: 10.1098/rsbl.2013.0562] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Diet selection in mammalian herbivores is thought to be mainly influenced by intrinsic factors such as nutrients and plant secondary compounds, yet extrinsic factors like ambient temperature may also play a role. In particular, warmer ambient temperatures could enhance the toxicity of plant defence compounds through decreased liver metabolism of herbivores. Temperature-dependent toxicity has been documented in pharmacology and agriculture science but not in wild mammalian herbivores. Here, we investigated how ambient temperature affects liver metabolism in the desert woodrat, Neotoma lepida. Woodrats (n = 21) were acclimated for 30 days to two ambient temperatures (cool = 21°C, warm = 29°C). In a second experiment, the temperature exposure was reduced to 3.5 h. After temperature treatments, animals were given a hypnotic agent and clearance time of the agent was estimated from the duration of the hypnotic state. The average clearance time of the agent in the long acclimation experiment was 45% longer for animals acclimated to 29°C compared with 21°C. Similarly, after the short exposure experiment, woodrats at 29°C had clearance times 26% longer compared with 21°C. Our results are consistent with the hypothesis that liver function is reduced at warmer environmental temperatures and may provide a physiological mechanism through which climate change affects herbivorous mammals.
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Affiliation(s)
- Patrice Kurnath
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA.
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30
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Barrio IC, Hik DS, Peck K, Bueno CG. After the frass: foraging pikas select patches previously grazed by caterpillars. Biol Lett 2013; 9:20130090. [PMID: 23616644 DOI: 10.1098/rsbl.2013.0090] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Interactions among herbivores can shape the structure of their communities and drive their dynamics. However, detecting herbivore interactions can be challenging when they are deferred in space or time. Moreover, interactions among distantly related groups of herbivores, such as vertebrates and invertebrates, are poorly understood. We investigated the effect of invertebrate herbivory on the subsequent foraging choices of a small alpine-dwelling vertebrate, the collared pika (Ochotona collaris). We carried out a field experiment within pika territories, by presenting them with a choice of foraging sites following manipulation of invertebrate (caterpillar) herbivory. Pikas actively selected areas with increased, recent invertebrate herbivory. While the underlying mechanisms behind this interaction remain unknown, our results demonstrate a positive effect of invertebrate herbivores on subsequent vertebrate foraging preferences for the first time. Even among distantly related taxa, such interactions where one herbivore is cueing on the foraging of another, could drive the creation of herbivory hotspots, with cascading consequences for ecosystem processes.
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Affiliation(s)
- Isabel C Barrio
- Department of Biological Sciences, University of Alberta, Edmonton, Canada T6G2E9.
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31
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A pharm-ecological perspective of terrestrial and aquatic plant-herbivore interactions. J Chem Ecol 2013; 39:465-80. [PMID: 23483346 DOI: 10.1007/s10886-013-0267-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2012] [Revised: 02/05/2013] [Accepted: 02/19/2013] [Indexed: 12/14/2022]
Abstract
We describe some recent themes in the nutritional and chemical ecology of herbivores and the importance of a broad pharmacological view of plant nutrients and chemical defenses that we integrate as "Pharm-ecology". The central role that dose, concentration, and response to plant components (nutrients and secondary metabolites) play in herbivore foraging behavior argues for broader application of approaches derived from pharmacology to both terrestrial and aquatic plant-herbivore systems. We describe how concepts of pharmacokinetics and pharmacodynamics are used to better understand the foraging phenotype of herbivores relative to nutrient and secondary metabolites in food. Implementing these concepts into the field remains a challenge, but new modeling approaches that emphasize tradeoffs and the properties of individual animals show promise. Throughout, we highlight similarities and differences between the historic and future applications of pharm-ecological concepts in understanding the ecology and evolution of terrestrial and aquatic interactions between herbivores and plants. We offer several pharm-ecology related questions and hypotheses that could strengthen our understanding of the nutritional and chemical factors that modulate foraging behavior of herbivores across terrestrial and aquatic systems.
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