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Martins LS, Costa-Schmidt LE, Garcia AM, Bastos RF, Rebelato MM, Tozetti AM. The Contribution of Aquatic Plants to the Trophic Ecology of a Sand Dune Lizard in Southern Brazil. SOUTH AMERICAN JOURNAL OF HERPETOLOGY 2021. [DOI: 10.2994/sajh-d-18-00045.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Laís S. Martins
- Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Avenida Itália, Km 8, CEP 96201-900, Rio Grande, Rio Grande do Sul, Brazil
| | - Luiz E. Costa-Schmidt
- Laboratório de Ecologia de Vertebrados Terrestres. Programa de Pós-Graduação em Biologia, Universidade do Vale do Rio dos Sinos, Avenida Unisinos, 950, CEP 93022-000, São Leopoldo, Rio Grande do Sul, Brazil
| | - Alexandre M. Garcia
- Laboratório de Ictiologia, Instituto de Oceanografia, Universidade Federal do Rio Grande, Avenida Itália, Km 8, Caixa Postal 474, CEP 96203-900, Rio Grande, Rio Grande do Sul, Brazil
| | - Rodrigo F. Bastos
- Laboratório de Nécton, Departamento de Oceanografia, Universidade Federal de Pernambuco, Avenida Arquitetura, s/n, Cidade Universitária, CEP 50740-550, Recife, Pernambuco, Brazil
| | - Marluci M. Rebelato
- Laboratório de Herpetologia, Departamento de Zoologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Avenida Bento Gonçalves, 9500, Agronomia, CEP 91501-970, Porto Alegre, Rio Grande do Sul, Brazil
| | - Alexandro M. Tozetti
- Laboratório de Ecologia de Vertebrados Terrestres. Programa de Pós-Graduação em Biologia, Universidade do Vale do Rio dos Sinos, Avenida Unisinos, 950, CEP 93022-000, São Leopoldo, Rio Grande do Sul, Brazil
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2
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Young FJ, Montgomery SH. Pollen feeding in Heliconius butterflies: the singular evolution of an adaptive suite. Proc Biol Sci 2020; 287:20201304. [PMID: 33171092 PMCID: PMC7735275 DOI: 10.1098/rspb.2020.1304] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 10/15/2020] [Indexed: 12/21/2022] Open
Abstract
Major evolutionary transitions can be triggered by behavioural novelty, and are often associated with 'adaptive suites', which involve shifts in multiple co-adapted traits subject to complex interactions. Heliconius butterflies represent one such example, actively feeding on pollen, a behaviour unique among butterflies. Pollen feeding permits a prolonged reproductive lifespan, and co-occurs with a constellation of behavioural, neuroanatomical, life history, morphological and physiological traits that are absent in closely related, non-pollen-feeding genera. As a highly tractable system, supported by considerable ecological and genomic data, Heliconius are an excellent model for investigating how behavioural innovation can trigger a cascade of adaptive shifts in multiple diverse, but interrelated, traits. Here, we synthesize current knowledge of pollen feeding in Heliconius, and explore potential interactions between associated, putatively adaptive, traits. Currently, no physiological, morphological or molecular innovation has been explicitly linked to the origin of pollen feeding, and several hypothesized links between different aspects of Heliconius biology remain poorly tested. However, resolving these uncertainties will contribute to our understanding of how behavioural innovations evolve and subsequently alter the evolutionary trajectories of diverse traits impacting resource acquisition, life history, senescence and cognition.
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Affiliation(s)
- Fletcher J. Young
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
- School of Biological Science, University of Bristol, 24 Tyndall Avenue, Bristol UBS8 1TQ, UK
| | - Stephen H. Montgomery
- School of Biological Science, University of Bristol, 24 Tyndall Avenue, Bristol UBS8 1TQ, UK
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3
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Lacombe RJS, Lee CC, Bazinet RP. Turnover of brain DHA in mice is accurately determined by tracer-free natural abundance carbon isotope ratio analysis. J Lipid Res 2020; 61:116-126. [PMID: 31712249 PMCID: PMC6939594 DOI: 10.1194/jlr.d119000518] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Indexed: 01/04/2023] Open
Abstract
The brain is highly enriched in the long-chain omega-3 (n-3) PUFA DHA. Due to the limited capacity for local DHA synthesis in the brain, it relies on a continual supply from the circulation to replenish metabolized DHA. Previous studies investigating brain DHA turnover and metabolism have relied on isotope tracers to determine brain fatty acid kinetics; however, this approach is cumbersome and costly. We applied natural abundance carbon isotope ratio analysis via high-precision gas chromatography combustion isotope ratio mass spectrometry, without the use of labeled tracers, to determine the half-life of brain DHA in mice following a dietary switch experiment. Mice fed diets containing either α-linolenic acid (ALA) or DHA as the sole dietary n-3 PUFA were switched onto diets containing ALA, DHA, or ALA + DHA at 6 weeks of age, while control mice were maintained on their respective background diet. We measured brain DHA carbon isotope ratios (reported as δ13CDHA signatures) over a 168-day time course. Brain δ13CDHA signatures of control mice maintained on background diets over the time course were stable (P > 0.05). Brain δ13CDHA signatures of mice switched to the DHA or ALA + DHA diet from the ALA diet changed over time, yielding brain incorporation half-lives of 40 and 34 days, respectively. These half-lives determined by natural abundance carbon isotope ratio analysis were consistent with estimates from kinetic isotope tracer studies. Our results demonstrate the feasibility of natural abundance carbon isotope ratio analysis in the study of fatty acid metabolism without the use of isotopically labeled fatty acid tracers.
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Affiliation(s)
- R J Scott Lacombe
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Chi-Chiu Lee
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
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4
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McCue MD, Javal M, Clusella‐Trullas S, Le Roux JJ, Jackson MC, Ellis AG, Richardson DM, Valentine AJ, Terblanche JS. Using stable isotope analysis to answer fundamental questions in invasion ecology: Progress and prospects. Methods Ecol Evol 2019. [DOI: 10.1111/2041-210x.13327] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Marshall D. McCue
- Sable Systems International Las Vegas NV USA
- Department of Conservation Ecology and Entomology Centre for Invasion Biology Stellenbosch University Stellenbosch South Africa
| | - Marion Javal
- Department of Conservation Ecology and Entomology Centre for Invasion Biology Stellenbosch University Stellenbosch South Africa
| | - Susana Clusella‐Trullas
- Centre for Invasion Biology Department of Botany and Zoology Stellenbosch University Stellenbosch South Africa
| | - Johannes J. Le Roux
- Centre for Invasion Biology Department of Botany and Zoology Stellenbosch University Stellenbosch South Africa
- Department of Biological Sciences Macquarie University NSW Australia
| | - Michelle C. Jackson
- Centre for Invasion Biology Department of Botany and Zoology Stellenbosch University Stellenbosch South Africa
- Department of Life Sciences Imperial College London Ascot UK
- Department of Zoology Oxford University Oxford UK
| | - Allan G. Ellis
- Department of Botany and Zoology Stellenbosch University Stellenbosch South Africa
| | - David M. Richardson
- Centre for Invasion Biology Department of Botany and Zoology Stellenbosch University Stellenbosch South Africa
| | - Alex J. Valentine
- Department of Botany and Zoology Stellenbosch University Stellenbosch South Africa
| | - John S. Terblanche
- Department of Conservation Ecology and Entomology Centre for Invasion Biology Stellenbosch University Stellenbosch South Africa
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5
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Hostachy C, Couzi P, Hanafi-Portier M, Portemer G, Halleguen A, Murmu M, Deisig N, Dacher M. Responsiveness to Sugar Solutions in the Moth Agrotis ipsilon: Parameters Affecting Proboscis Extension. Front Physiol 2019; 10:1423. [PMID: 31849694 PMCID: PMC6888557 DOI: 10.3389/fphys.2019.01423] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 11/04/2019] [Indexed: 12/05/2022] Open
Abstract
Adult moths need energy and nutrients for reproducing and obtain them mainly by consuming flower nectar (a solution of sugars and other compounds). Gustatory perception gives them information on the plants they feed on. Feeding and food perception are integrated in the proboscis extension response, which occurs when their antennae touch a sugar solution. We took advantage of this reflex to explore moth sugar responsiveness depending on different parameters (i.e., sex, age, satiety, site of presentation, and composition of the solution). We observed that starvation but not age induced higher response rates to sucrose. Presentation of sucrose solutions in a randomized order confirmed that repeated sugar stimulations did not affect the response rate; however, animals were sometimes sensitized to water, indicating sucrose presentation might induce non-associative plasticity. Leg stimulation was much less efficient than antennal stimulation to elicit a response. Quinine prevented and terminated sucrose-elicited proboscis extension. Males but not females responded slightly more to sucrose than to fructose. Animals of either sex rarely reacted to glucose, but curiously, mixtures in which half sucrose or fructose were replaced by glucose elicited the same response rate than sucrose or fructose alone. Fructose synergized the response when mixed with sucrose in male but not female moths. This is consistent with the fact that nectars consumed by moths in nature are mixtures of these three sugars, which suggests an adaptation to nectar perception.
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Affiliation(s)
| | | | | | | | | | | | | | - Matthieu Dacher
- Sorbonne Université, Université Paris Est Créteil, INRA, CNRS, IRD – Institute for Ecology and Environmental Sciences of Paris (iEES Paris), Paris, France
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6
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Pettit TV, Pettit RJ, Durso AM, French SS. Investment of both essential fatty and amino acids to immunity varies depending on reproductive stage. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2019; 331:552-561. [PMID: 31625280 DOI: 10.1002/jez.2324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 08/10/2019] [Accepted: 09/08/2019] [Indexed: 12/29/2022]
Abstract
Trade-offs among the key life-history traits of reproduction and immunity have been widely documented. However, the currency in use is not well-understood. We investigated how reproducing female side-blotched lizards, Uta stansburiana, allocate lipids versus proteins when given an immune challenge. We tested whether lizards would invest more in reproduction or immunity depending on reproductive stage. Females were given stable isotopes (15 N-leucine and 13 C-1-palmitic acid), maintained on a regular diet and given either a cutaneous biopsy or a sham biopsy (control). Stable isotopes were monitored and analyzed in feces and uric acid, skin biopsies, eggs, and toe clips. We found that lizards deposited both proteins and lipids into their healing wounds (immune-challenged), skin (control), and eggs (all) and that catabolism of proteins exceeded incorporation into tissue during wound-healing. Specifically, we found that healed biopsies of wounded animals had more leucine and palmitic acid than the nonregrown skin biopsies taken from unwounded control animals. Earlier in reproduction, lizards invested relatively more labeled proteins into healing their wound tissue, but not into unwounded skin of control animals. Thus, reproduction is sometimes favored over self-maintenance, but only in later reproductive stages. Finally, we documented positive relationships among the amount of palmitic acid deposited in the eggs, the amount of food eaten, and the amount of palmitic acid excreted, suggesting higher turnover rates of lipids in lizards investing highly in their eggs.
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Affiliation(s)
- Taylor V Pettit
- Department of Biology and the Ecology Center, Utah State University, Logan, Utah
| | - R John Pettit
- Department of Biology and the Ecology Center, Utah State University, Logan, Utah
| | - Andrew M Durso
- Department of Biology and the Ecology Center, Utah State University, Logan, Utah
| | - Susannah S French
- Department of Biology and the Ecology Center, Utah State University, Logan, Utah
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7
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Mozuraitis R, Murtazina R, Zurita J, Pei Y, Ilag L, Wiklund C, Karlson AKB. Anti-aphrodisiac pheromone, a renewable signal in adult butterflies. Sci Rep 2019; 9:14262. [PMID: 31582781 PMCID: PMC6776535 DOI: 10.1038/s41598-019-50838-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 09/09/2019] [Indexed: 11/09/2022] Open
Abstract
The male butterfly Pieris napi produces the anti-aphrodisiac pheromone methyl salicylate (MeS) and transfers it to the female during mating. After mating she releases MeS, when courted by conspecific males, which decreases her attractiveness and the duration of male harassment, thus increasing her time available for egg-laying. In previous studies we have shown that males produced MeS from the amino acid L-phenylalanine (L-Phe) acquired during larval stage. In this study we show that adult males of P. napi can utilize L-Phe and aromatic flower volatiles as building blocks for production of anti-aphrodisiac pheromone and transfer it to females during mating. We demonstrate this by feeding butterflies with stable isotope labelled molecules mixed in sugar solutions, and, to mimic the natural conditions, we fed male butterflies with floral nectar of Bunias orientalis plants treated with labelled L-Phe. The volatiles from butterflies and plants were collected and identified by solid phase micro extraction, gas chromatography and mass spectrometry techniques. Since P. napi is polygamous, males would gain from restoring the titre of MeS after mating and the use of aromatic precursors for production of MeS could be considered as an advantageous trait which could enable butterflies to relocate L-Phe for other needs.
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Affiliation(s)
- Raimondas Mozuraitis
- Department of Zoology, Stockholm University, SE-10691, Stockholm, Sweden. .,Laboratory of Chemical and Behavioural Ecology, Institute of Ecology, Nature Research Centre, Akademijos 2, LT-08412, Vilnius, Lithuania.
| | - Rushana Murtazina
- Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, Royal Institute of Technology, KTH, SE-100 44, Stockholm, Sweden
| | - Javier Zurita
- Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-10691, Stockholm, Sweden
| | - Yuxin Pei
- Northwest A&F University, Department of Applied Chemistry, Yangling, Shaanxi, 712100, People's Republic of China
| | - Leopold Ilag
- Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-10691, Stockholm, Sweden
| | - Christer Wiklund
- Department of Zoology, Stockholm University, SE-10691, Stockholm, Sweden
| | - Anna Karin Borg Karlson
- Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, Royal Institute of Technology, KTH, SE-100 44, Stockholm, Sweden.,Division of Organic Chemistry, Institute of Technology, Tartu University, Tartu, 50411, Estonia
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8
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Stöckl AL, Kelber A. Fuelling on the wing: sensory ecology of hawkmoth foraging. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2019; 205:399-413. [PMID: 30880349 PMCID: PMC6579779 DOI: 10.1007/s00359-019-01328-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 02/25/2019] [Accepted: 03/05/2019] [Indexed: 11/28/2022]
Abstract
Hawkmoths (Lepidoptera, Sphingidae) comprise around 1500 species, most of which forage on nectar from flowers in their adult stage, usually while hovering in front of the flower. The majority of species have a nocturnal lifestyle and are important nocturnal pollinators, but some species have turned to a diurnal lifestyle. Hawkmoths use visual and olfactory cues including CO2 and humidity to detect and recognise rewarding flowers; they find the nectary in the flowers by means of mechanoreceptors on the proboscis and vision, evaluate it with gustatory receptors on the proboscis, and control their hovering flight position using antennal mechanoreception and vision. Here, we review what is presently known about the sensory organs and sensory-guided behaviour that control feeding behaviour of this fascinating pollinator taxon. We also suggest that more experiments on hawkmoth behaviour in natural settings are needed to fully appreciate their sensory capabilities.
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Affiliation(s)
- Anna Lisa Stöckl
- Biozentrum, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Almut Kelber
- Department of Biology, Lund University, Sölvegatan 35, 22362, Lund, Sweden.
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9
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Ejsmond MJ, McNamara JM, Søreide J, Varpe Ø. Gradients of season length and mortality risk cause shifts in body size, reserves and reproductive strategies of determinate growers. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13191] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Maciej J. Ejsmond
- Institute of Environmental SciencesJagiellonian University Kraków Poland
- Department of Arctic BiologyUniversity Centre in Svalbard Longyearbyen Norway
| | | | - Janne Søreide
- Department of Arctic BiologyUniversity Centre in Svalbard Longyearbyen Norway
| | - Øystein Varpe
- Department of Arctic BiologyUniversity Centre in Svalbard Longyearbyen Norway
- Akvaplan‐nivaFram Centre Tromsø Norway
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10
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González-Ortegón E, Vay LL, Walton MEM, Giménez L. Maternal Trophic Status and Offpsring Phenotype in a Marine Invertebrate. Sci Rep 2018; 8:9618. [PMID: 29941878 PMCID: PMC6018471 DOI: 10.1038/s41598-018-27709-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 05/27/2018] [Indexed: 11/17/2022] Open
Abstract
Offspring size variation in relation to maternal size and season is characteristic of a range of species living in seasonal environments. Little is known about the proximate mechanisms explaining the links between maternally driven variation in offspring phenotypes, for instance when mothers have different diets depending on their size or the season. Here, we use stable isotopes techniques to quantify size dependent and seasonal variations in diet in mothers of shrimp Palaemon serratus and explore possible links between maternal diet and phenotype of embryos and freshly hatched larvae. We found that larger females, which occur more frequently in winter, produce larvae with higher carbon and nitrogen content as well as higher percent carbon, than smaller mothers collected in winter. In addition, isotopic composition suggest that larger mothers collected in winter, were feeding at a higher trophic level, or on an enriched prey pool compared with smaller mothers collected in summer. Overall, there seems to be a strong association between offspring size and maternal diet, mediated by maternal size and/or season.
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Affiliation(s)
- Enrique González-Ortegón
- Instituto de Ciencias Marinas de Andalucía (ICMAN-CSIC), Campus Universitario Río San Pedro, 11519, Puerto Real, Cádiz, Spain. .,School of Ocean Sciences, Bangor University, Menai Bridge, LL59 5AB, UK. .,CEI-MAR International Campus of Excellence of the Sea, Cádiz, Spain.
| | - Lewis Le Vay
- School of Ocean Sciences, Bangor University, Menai Bridge, LL59 5AB, UK
| | | | - Luis Giménez
- School of Ocean Sciences, Bangor University, Menai Bridge, LL59 5AB, UK
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11
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Levin E, McCue MD, Davidowitz G. More than just sugar: allocation of nectar amino acids and fatty acids in a Lepidopteran. Proc Biol Sci 2018; 284:rspb.2016.2126. [PMID: 28148746 DOI: 10.1098/rspb.2016.2126] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 01/05/2017] [Indexed: 01/19/2023] Open
Abstract
The ability to allocate resources, even when limited, is essential for survival and fitness. We examine how nutrients that occur in minute amounts are allocated among reproductive, somatic, and metabolic demands. In addition to sugar, flower nectars contain two macronutrients-amino acids and fatty acids. We created artificial nectars spiked with 13C-labelled amino acids and fatty acids and fed these to adult moths (Manduca sexta: Sphingidae) to understand how they allocate these nutrients among competing sinks (reproduction, somatic tissue, and metabolic fuel). We found that both essential and non-essential amino acids were allocated to eggs and flight muscles and were still detectable in early-instar larvae. Parental-derived essential amino acids were more conserved in the early-instars than non-essential amino acids. All amino acids were used as metabolic fuel, but the non-essential amino acids were oxidized at higher rates than essential amino acids. Surprisingly, the nectar fatty acids were not vertically transferred to offspring, but were readily used as a metabolic fuel by the moth, minimizing losses of endogenous nutrient stores. We conclude that the non-carbohydrate components of nectar may play important roles in both reproductive success and survival of these nectar-feeding animals.
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Affiliation(s)
- Eran Levin
- Department of Entomology, University of Arizona, Tucson, AZ, USA
| | - Marshall D McCue
- Department of Biological Sciences, St. Mary's University, San Antonio, TX, USA
| | - Goggy Davidowitz
- Department of Entomology, University of Arizona, Tucson, AZ, USA
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12
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Hughes KL, Whiteman JP, Newsome SD. The relationship between dietary protein content, body condition, and Δ15N in a mammalian omnivore. Oecologia 2017; 186:357-367. [DOI: 10.1007/s00442-017-4010-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 11/09/2017] [Indexed: 11/29/2022]
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13
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Lacombe RJS, Giuliano V, Colombo SM, Arts MT, Bazinet RP. Compound-specific isotope analysis resolves the dietary origin of docosahexaenoic acid in the mouse brain. J Lipid Res 2017; 58:2071-2081. [PMID: 28694298 DOI: 10.1194/jlr.d077990] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/05/2017] [Indexed: 12/23/2022] Open
Abstract
DHA (22:6n-3) may be derived from two dietary sources, preformed dietary DHA or through synthesis from α-linolenic acid (ALA; 18:3n-3). However, conventional methods cannot distinguish between DHA derived from either source without the use of costly labeled tracers. In the present study, we demonstrate the proof-of-concept that compound-specific isotope analysis (CSIA) by GC-isotope ratio mass spectrometry (IRMS) can differentiate between sources of brain DHA based on differences in natural 13C enrichment. Mice were fed diets containing either purified ALA or DHA as the sole n-3 PUFA. Extracted lipids were analyzed by CSIA for natural abundance 13C enrichment. Brain DHA from DHA-fed mice was significantly more enriched (-23.32‰ to -21.92‰) compared with mice on the ALA diet (-28.25‰ to -27.49‰). The measured 13C enrichment of brain DHA closely resembled the dietary n-3 PUFA source, -21.86‰ and -28.22‰ for DHA and ALA, respectively. The dietary effect on DHA 13C enrichment was similar in liver and blood fractions. Our results demonstrate the effectiveness of CSIA, at natural 13C enrichment, to differentiate between the incorporation of preformed or synthesized DHA into the brain and other tissues without the need for tracers.
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Affiliation(s)
- R J Scott Lacombe
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Vanessa Giuliano
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
| | - Stefanie M Colombo
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario M5B 2K3, Canada
| | - Michael T Arts
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario M5B 2K3, Canada
| | - Richard P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 3E2, Canada
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14
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Levin E, McCue MD, Davidowitz G. Sex differences in the utilization of essential and non-essential amino acids in Lepidoptera. ACTA ACUST UNITED AC 2017; 220:2743-2747. [PMID: 28495867 DOI: 10.1242/jeb.154757] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 05/08/2017] [Indexed: 01/04/2023]
Abstract
The different reproductive strategies of males and females underlie differences in behavior that may also lead to differences in nutrient use between the two sexes. We studied sex differences in the utilization of two essential amino acids (EAAs) and one non-essential amino acid (NEAA) by the Carolina sphinx moth (Manduca sexta). On day one post-eclosion from the pupae, adult male moths oxidized greater amounts of larva-derived AAs than females, and more nectar-derived AAs after feeding. After 4 days of starvation, the opposite pattern was observed: adult females oxidized more larva-derived AAs than males. Adult males allocated comparatively small amounts of nectar-derived AAs to their first spermatophore, but this allocation increased substantially in the second and third spermatophores. Males allocated significantly more adult-derived AAs to their flight muscle than females. These outcomes indicate that adult male and female moths employ different strategies for allocation and oxidation of dietary AAs.
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Affiliation(s)
- Eran Levin
- Department of Entomology, University of Arizona, Tucson, AZ 85721, USA
| | - Marshall D McCue
- Department of Biological Sciences, St Mary's University, San Antonio, TX 78228, USA
| | - Goggy Davidowitz
- Department of Entomology, University of Arizona, Tucson, AZ 85721, USA
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15
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Broadhead GT, Basu T, von Arx M, Raguso RA. Diel rhythms and sex differences in the locomotor activity of hawkmoths. ACTA ACUST UNITED AC 2017; 220:1472-1480. [PMID: 28153982 DOI: 10.1242/jeb.143966] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 01/30/2017] [Indexed: 12/25/2022]
Abstract
Circadian patterns of activity are considered ubiquitous and adaptive, and are often invoked as a mechanism for temporal niche partitioning. Yet, comparisons of rhythmic behavior in related animal species are uncommon. This is particularly true of Lepidoptera (butterflies and moths), in which studies of whole-animal patterns of behavior are far outweighed by examinations of tissue-specific molecular clocks. Here, we used a comparative approach to examine the circadian patterns of flight behavior in Manduca sexta and Hyles lineata [two distantly related species of hawkmoth (Sphingidae)]. By filming isolated, individual animals, we were able to examine rhythmic locomotor (flight) activity at the species level, as well as at the level of the individual sexes, and in the absence of interference from social interaction. Our results confirmed classic descriptions of strictly nocturnal behavior in M. sexta and demonstrated a dramatically different activity pattern in H. lineata Furthermore, we showed distinct species and sex-specific differences in the maintenance of the endogenous rhythm under conditions of constant darkness. In both species, female activity peaked in advance of males whereas male activity coincided with periods of female sexual receptivity. This suggests a role for circadian patterns of locomotor activity in synchronizing periods of sexual receptivity between the sexes.
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Affiliation(s)
- Geoffrey T Broadhead
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14850, USA
| | - Trisha Basu
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14850, USA
| | - Martin von Arx
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14850, USA
| | - Robert A Raguso
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14850, USA
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Davis RB, Javoiš J, Kaasik A, Õunap E, Tammaru T. An ordination of life histories using morphological proxies: capital vs. income breeding in insects. Ecology 2016; 97:2112-2124. [DOI: 10.1002/ecy.1435] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 12/09/2015] [Accepted: 03/08/2016] [Indexed: 11/12/2022]
Affiliation(s)
- Robert B. Davis
- Department of Zoology; Institute of Ecology and Earth Sciences; University of Tartu; Vanemuise 46 EE-51014 Tartu Estonia
| | - Juhan Javoiš
- Department of Zoology; Institute of Ecology and Earth Sciences; University of Tartu; Vanemuise 46 EE-51014 Tartu Estonia
| | - Ants Kaasik
- Department of Zoology; Institute of Ecology and Earth Sciences; University of Tartu; Vanemuise 46 EE-51014 Tartu Estonia
| | - Erki Õunap
- Department of Zoology; Institute of Ecology and Earth Sciences; University of Tartu; Vanemuise 46 EE-51014 Tartu Estonia
- Institute of Agricultural and Environmental Sciences; Estonian University of Life Sciences; Kreutzwaldi 5 EE-51014 Tartu Estonia
| | - Toomas Tammaru
- Department of Zoology; Institute of Ecology and Earth Sciences; University of Tartu; Vanemuise 46 EE-51014 Tartu Estonia
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17
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Haverkamp A, Bing J, Badeke E, Hansson BS, Knaden M. Innate olfactory preferences for flowers matching proboscis length ensure optimal energy gain in a hawkmoth. Nat Commun 2016; 7:11644. [PMID: 27173441 PMCID: PMC4869250 DOI: 10.1038/ncomms11644] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 04/18/2016] [Indexed: 11/28/2022] Open
Abstract
Cost efficient foraging is of especial importance for animals like hawkmoths or hummingbirds that are feeding 'on the wing', making their foraging energetically demanding. The economic decisions made by these animals have a strong influence on the plants they pollinate and floral volatiles are often guiding these decisions. Here we show that the hawkmoth Manduca sexta exhibits an innate preference for volatiles of those Nicotiana flowers, which match the length of the moth's proboscis. This preference becomes apparent already at the initial inflight encounter, with the odour plume. Free-flight respiration analyses combined with nectar calorimetry revealed a significant caloric gain per invested flight energy only for preferred-matching-flowers. Our data therefore support Darwin's initial hypothesis on the coevolution of flower length and moth proboscis. We demonstrate that this interaction is mediated by an adaptive and hardwired olfactory preference of the moth for flowers offering the highest net-energy reward.
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Affiliation(s)
- Alexander Haverkamp
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
| | - Julia Bing
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
| | - Elisa Badeke
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
| | - Bill S. Hansson
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
| | - Markus Knaden
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll Straße 8, D-07745 Jena, Germany
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18
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Crowley BE, Reitsema LJ, Oelze VM, Sponheimer M. Advances in primate stable isotope ecology-Achievements and future prospects. Am J Primatol 2015; 78:995-1003. [PMID: 26683892 DOI: 10.1002/ajp.22510] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 12/28/2022]
Abstract
Stable isotope biogeochemistry has been used to investigate foraging ecology in non-human primates for nearly 30 years. Whereas early studies focused on diet, more recently, isotopic analysis has been used to address a diversity of ecological questions ranging from niche partitioning to nutritional status to variability in life history traits. With this increasing array of applications, stable isotope analysis stands to make major contributions to our understanding of primate behavior and biology. Most notably, isotopic data provide novel insights into primate feeding behaviors that may not otherwise be detectable. This special issue brings together some of the recent advances in this relatively new field. In this introduction to the special issue, we review the state of isotopic applications in primatology and its origins and describe some developing methodological issues, including techniques for analyzing different tissue types, statistical approaches, and isotopic baselines. We then discuss the future directions we envision for the field of primate isotope ecology. Am. J. Primatol. 78:995-1003, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Brooke E Crowley
- Departments of Geology and Anthropology, University of Cincinnati, Cincinnati, Ohio.
| | | | - Vicky M Oelze
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Matt Sponheimer
- Department of Anthropology, University of Colorado, Boulder, Colorado
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19
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Llandres AL, Marques GM, Maino JL, Kooijman SALM, Kearney MR, Casas J. A dynamic energy budget for the whole life-cycle of holometabolous insects. ECOL MONOGR 2015. [DOI: 10.1890/14-0976.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Chen CCW, Welch KC. Hummingbirds can fuel expensive hovering flight completely with either exogenous glucose or fructose. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12202] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Chris Chin Wah Chen
- Department of Biological Sciences University of Toronto Scarborough 1265 Military TrailToronto Ontario M1C 1A4 Canada
- Department of Cell & Systems Biology University of Toronto 25 Harbord StreetToronto Ontario M5S 3G5 Canada
| | - Kenneth Collins Welch
- Department of Biological Sciences University of Toronto Scarborough 1265 Military TrailToronto Ontario M1C 1A4 Canada
- Department of Cell & Systems Biology University of Toronto 25 Harbord StreetToronto Ontario M5S 3G5 Canada
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21
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Foster SP, Anderson KG, Harmon JP. Increased allocation of adult-acquired carbohydrate to egg production results in its decreased allocation to sex pheromone production in mated females of the moth Heliothis virescens. ACTA ACUST UNITED AC 2013; 217:499-506. [PMID: 24198254 DOI: 10.1242/jeb.095406] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Females of most species of moths produce a volatile sex pheromone that attracts conspecific males over distance. In females of the polyandrous moth Heliothis virescens, feeding on carbohydrate (e.g. nectar) supplies precursor, via hemolymph trehalose, for both sex pheromone and egg production. With limited carbohydrate acquisition these two reproductive physiologies might compete for hemolymph trehalose, resulting in an allocation deficit to either sex pheromone or egg production. Using virgin and mated females, which have low and high egg maturation rates, respectively, we fed females a limited diet of (13)C-labeled glucose daily and, using mass isotopomer distribution analysis, determined allocations of adult-acquired carbohydrate (AAC) to newly synthesized pheromone and ovarian and egg fats, our proxies for allocation to egg production. With increased number of feeds, AAC enrichment of hemolymph trehalose increased, as expected. This led to mated females increasing their proportional allocation of AAC to ovarian and egg fats, but decreasing their proportional allocation of AAC to pheromone production. By contrast, virgins increased their proportional allocation of AAC to pheromone production with increased feeds, consistent with increasing AAC enrichment of hemolymph trehalose. These results show that with limited AAC intake, enhanced egg maturation in mated females results in reduced AAC allocation to pheromone production; this does not occur in virgins because of their lower egg maturation rate. This physiological competition for AAC corresponded with decreased pheromone production in mated moths to levels unlikely to attract mates. Therefore, the availability and/or allocation of AAC may be a proximate mechanism underlying the incidence of polyandry in this and other species of moths.
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Affiliation(s)
- Stephen P Foster
- Entomology Department, North Dakota State University, PO Box 6050, Fargo, ND 58108-6050, USA
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22
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Ortega-Jimenez VM, Greeter JSM, Mittal R, Hedrick TL. Hawkmoth flight stability in turbulent vortex streets. ACTA ACUST UNITED AC 2013; 216:4567-79. [PMID: 24072794 DOI: 10.1242/jeb.089672] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Shedding of vortices is a common phenomenon in the atmosphere over a wide range of spatial and temporal scales. However, it is unclear how these vortices of varying scales affect the flight performance of flying animals. In order to examine these interactions, we trained seven hawkmoths (Manduca sexta) (wingspan ~9 cm) to fly and feed in a wind tunnel under steady flow (controls) and in the von Kármán vortex street of vertically oriented cylinders (two different cylinders with diameters of 10 and 5 cm) at speeds of 0.5, 1 and 2 m s(-1). Cylinders were placed at distances of 5, 25 and 100 cm upstream of the moths. Moths exhibited large amplitude yaw oscillations coupled with modest oscillations in roll and pitch, and slight increases in wingbeat frequency when flying in both the near (recirculating) and middle (vortex dominated) wake regions. Wingbeat amplitude did not vary among treatments, except at 1 m s(-1) for the large cylinder. Yaw and roll oscillations were synchronized with the vortex shedding frequencies in moths flying in the wake of the large cylinder at all speeds. In contrast, yaw and pitch were synchronized with the shedding frequency of small vortices at speeds ≤1 m s(-1). Oscillations in body orientation were also substantially smaller in the small cylinder treatment when compared with the large cylinder, regardless of temporal or non-dimensional spatial scale. Moths flying in steady conditions reached a higher air speed than those flying into cylinder wakes. In general, flight effects produced by the cylinder wakes were qualitatively similar among the recirculating and vortex-dominated wake regions; the magnitude of those effects, however, declined gradually with downstream distance.
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23
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Liberoff AL, Riva Rossi CM, Fogel ML, Ciancio JE, Pascual MA. Shifts in δ15 N signature following the onset of exogenous feeding in rainbow trout Oncorhynchus mykiss: importance of combining length and age data. JOURNAL OF FISH BIOLOGY 2013; 82:1423-1432. [PMID: 23557318 DOI: 10.1111/jfb.12063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Accepted: 01/16/2013] [Indexed: 06/02/2023]
Abstract
The δ(15) N isotopic change of recently emerged rainbow trout Oncorhynchus mykiss due to diet shift from yolk sac to exogenous feeding was evaluated in a field study. The fit of a general model including both fish length and age in days as co-variables indicates that the specific δ(15) N of individual fish at any given time along the ontogeny is determined by its growth trajectory. The results suggest that estimations based on fish size alone could bias data interpretation and maternal origin determinations in partially migratory salmonids.
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Affiliation(s)
- A L Liberoff
- Centro Nacional Patagónico-CONICET, Boulevard Brown 2915, 9120, Puerto Madryn, Chubut, Argentina.
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24
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von Arx M, Sullivan KA, Raguso RA. Dual fitness benefits of post-mating sugar meals for female hawkmoths (Hyles lineata). JOURNAL OF INSECT PHYSIOLOGY 2013; 59:458-465. [PMID: 23376765 DOI: 10.1016/j.jinsphys.2013.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 01/18/2013] [Accepted: 01/21/2013] [Indexed: 06/01/2023]
Abstract
The white-lined sphinx moth (Hyles lineata: Sphingidae) is the most widespread and abundant hawkmoth pollinator in North America and plays a major role in the reproductive biology of many plant species. H. lineata visits a wide range of plants, which differ in the quality and quantity (e.g. caloric content, volume) of the nectar reward that they offer in exchange for pollination services. Some of these plants represent a suitable oviposition substrate as well as a profitable nectar source, allowing mated H. lineata females to mix foraging and oviposition bouts. We investigated the effects of post-mating nectar intake on the reproductive success of female H. lineata. While all experimental females had access to a 20% sucrose solution during the pre-mating phase (avg. 2.7 days) we manipulated the post-mating diet, assigning mated females to three experimental groups (sucrose fed, water fed, or unfed). Mated females with access to sucrose lived twice as long and produced more fertile eggs at double the rate of control moths that were starved or water-fed after mating. Thus, the sugar component of floral nectar positively affects the physiology of mated H. lineata at multiple levels, which translates into strong selection for mated females to continue nectar foraging during or between oviposition bouts.
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Affiliation(s)
- Martin von Arx
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
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25
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Laycock I, Lenthall KM, Barratt AT, Cresswell JE. Effects of imidacloprid, a neonicotinoid pesticide, on reproduction in worker bumble bees (Bombus terrestris). ECOTOXICOLOGY (LONDON, ENGLAND) 2012; 21:1937-1945. [PMID: 22614036 DOI: 10.1007/s10646-012-0927-y] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/04/2012] [Indexed: 06/01/2023]
Abstract
Bumble bees are important pollinators whose populations have declined over recent years, raising widespread concern. One conspicuous threat to bumble bees is their unintended exposure to trace residues of systemic neonicotinoid pesticides, such as imidacloprid, which are ingested when bees forage on the nectar and pollen of treated crops. However, the demographic consequences for bumble bees of exposure to dietary neonicotinoids have yet to be fully established. To determine whether environmentally realistic levels of imidacloprid are capable of making a demographic impact on bumble bees, we exposed queenless microcolonies of worker bumble bees, Bombus terrestris, to a range of dosages of dietary imidacloprid between zero and 125 μg L(-1) and examined the effects on ovary development and fecundity. Microcolonies showed a dose-dependent decline in fecundity, with environmentally realistic dosages in the range of 1 μg L(-1) capable of reducing brood production by one third. In contrast, ovary development was unimpaired by dietary imidacloprid except at the highest dosage. Imidacloprid reduced feeding on both syrup and pollen but, after controlling statistically for dosage, microcolonies that consumed more syrup and pollen produced more brood. We therefore speculate that the detrimental effects of imidacloprid on fecundity emerge principally from nutrient limitation imposed by the failure of individuals to feed. Our findings raise concern about the impact of neonicotinoids on wild bumble bee populations. However, we recognize that to fully evaluate impacts on wild colonies it will be necessary to establish the effect of dietary neonicotinoids on the fecundity of bumble bee queens.
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Affiliation(s)
- Ian Laycock
- Department of Biosciences, College of Life & Environmental Sciences, University of Exeter, Hatherly Laboratories, Prince of Wales Road, Exeter, EX4 4PS, UK.
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26
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Marchioro CA, Foerster LA. Performance of the wheat armyworm, Pseudaletia sequax Franclemont, on natural and artificial diets. NEOTROPICAL ENTOMOLOGY 2012; 41:288-295. [PMID: 23950064 DOI: 10.1007/s13744-012-0046-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 05/07/2012] [Indexed: 06/02/2023]
Abstract
Armyworms in the genus Pseudaletia Franclemont are important pests of cereal crops worldwide. The development of pest management strategies is largely dependent on studies involving the relationship among the pest, its host plants and natural enemies, as well as its susceptibility to chemical and biological control strategies. Part of these studies requires rearing the species of interest under laboratory conditions, which can be greatly facilitated by the use of artificial diets. In the present study, the effects of three artificial diets on development, survival, reproduction and demographic parameters of P. sequax were compared to a natural host plant, Pennisetum clandestinum. A diet based on pinto beans, wheat germ and torula yeast provided the best results in comparison to those obtained with the host plant. The most important life history parameters used in the evaluation of the nutritional quality of the diets were fecundity, egg viability and pupae deformities. The intrinsic rate of increase and the net reproductive rate were higher when individuals were fed on the artificial diet if compared to the host plant, indicating the suitability of the tested diet for the rearing of P. sequax. This artificial diet has been used successfully for the rearing of P. sequax without any fitness effect for over 18 consecutive generations.
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Affiliation(s)
- C A Marchioro
- Depto de Zoologia, Univ Federal do Paraná, Curitiba, PR, Brasil
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27
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Warne RW, Gilman CA, Garcia DA, Wolf BO. Capital Breeding and Allocation to Life-History Demands Are Highly Plastic in Lizards. Am Nat 2012; 180:130-41. [DOI: 10.1086/665995] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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28
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Nectar amino acids enhance reproduction in male butterflies. Oecologia 2012; 171:197-205. [DOI: 10.1007/s00442-012-2395-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 06/06/2012] [Indexed: 10/28/2022]
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29
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Boecklen WJ, Yarnes CT, Cook BA, James AC. On the Use of Stable Isotopes in Trophic Ecology. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2011. [DOI: 10.1146/annurev-ecolsys-102209-144726] [Citation(s) in RCA: 623] [Impact Index Per Article: 47.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- William J. Boecklen
- Laboratory of Ecological Chemistry, Department of Biology, New Mexico State University, Las Cruces, New Mexico 88003; , ,
| | - Christopher T. Yarnes
- Stable Isotope Facility, Department of Plant Sciences, University of California, Davis, Davis, California 95616;
| | - Bethany A. Cook
- Laboratory of Ecological Chemistry, Department of Biology, New Mexico State University, Las Cruces, New Mexico 88003; , ,
| | - Avis C. James
- Laboratory of Ecological Chemistry, Department of Biology, New Mexico State University, Las Cruces, New Mexico 88003; , ,
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30
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Potter KA, Woods HA. No evidence for the evolution of thermal or desiccation tolerance of eggs among populations ofManduca sexta. Funct Ecol 2011. [DOI: 10.1111/j.1365-2435.2011.01912.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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31
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Foster SP, Johnson CP. Signal Honesty through Differential Quantity in the Female-Produced Sex Pheromone of the Moth Heliothis virescens. J Chem Ecol 2011; 37:717-23. [DOI: 10.1007/s10886-011-9982-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 05/12/2011] [Accepted: 06/07/2011] [Indexed: 10/18/2022]
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32
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Travers SE, Fauske GM, Fox K, Ross AA, Harris MO. The Hidden Benefits of Pollinator Diversity for the Rangelands of the Great Plains: Western Prairie Fringed Orchids as a Case Study. ACTA ACUST UNITED AC 2011. [DOI: 10.2111/1551-501x-33.3.20] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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33
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Tracking the Oxidative and Nonoxidative Fates of Isotopically Labeled Nutrients in Animals. Bioscience 2011. [DOI: 10.1525/bio.2011.61.3.7] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Foster SP, Johnson CP. Feeding and hemolymph trehalose concentration influence sex pheromone production in virgin Heliothis virescens moths. JOURNAL OF INSECT PHYSIOLOGY 2010; 56:1617-1623. [PMID: 20540946 DOI: 10.1016/j.jinsphys.2010.06.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 05/28/2010] [Accepted: 06/02/2010] [Indexed: 05/29/2023]
Abstract
Previously, we demonstrated that sex pheromone production in mated female Heliothis virescens moths is dependent upon hemolymph trehalose concentration (HTC), which is influenced by activities such as the feeding of adults on sucrose. In this paper we demonstrate, for the first time, that this effect also occurs in starved (i.e., sugar-stressed) virgin females. Females allowed to feed on sugar for 6 days, following eclosion, had significantly greater titers than females that had fed only on water (i.e., were starved). No differences in pheromone titer were observed between sugar- and water-fed females at shorter (1 or 3 days) periods following eclosion. The relatively short-term effects of HTC on sex pheromone titer of virgins, were demonstrated by feeding experiments, in which starved (for 4 days) virgins fed on 10% sucrose solution had significantly greater HTC and pheromone titers than ones fed only on water; an increase in HTC was apparent within an hour, while the increase in pheromone titer was apparent within 2.5h, of sugar feeding. Starvation also showed similar effects on titers of pheromone gland fatty acids (pheromone intermediates) and HTC. Over 6 days of starvation, fatty acid titers and HTC declined gradually. After feeding on sucrose, titers of hexadecanoic, (Z)-9-hexadecanoic, (Z)-11-hexadecanoic and (Z)-9-octadecanoic, acids, as well as HTC, increased significantly 24h later, but titers of octadecanoic and (Z,Z)-9,12-octadecanoic (linoleic) acids did not. Lepidoptera cannot biosynthesize polyunsaturated acids, but the lack of change in octadecanoic acid titer suggests this acid may not participate in pheromone biosynthesis. In addition to these short-term changes in pheromone and fatty acid production, mediated by HTC, a longer-term effect of age, regardless of HTC, on pheromone titer was observed. Overall, these results are consistent with hemolymph trehalose and glandular fatty acids acting as twin metabolite reservoirs for pheromone biosynthesis. Hemolymph trehalose, able to be refilled through feeding on exogenous sugars, has a one-way flow of metabolites for synthesis of glandular free fatty acids (FFAs) and pheromone, while glandular glycerolipids provide a reversible reservoir for metabolites, accepting surplus FFAs when glandular concentrations are high, and providing FFAs for pheromone biosynthesis when concentrations are low.
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Affiliation(s)
- Stephen P Foster
- Entomology Department, North Dakota State University, Fargo, ND 58108-6050, USA.
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35
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Carsten-Conner LD, Papaj DR, O'Brien DM. Resource allocation to testes in walnut flies and implications for reproductive strategy. JOURNAL OF INSECT PHYSIOLOGY 2010; 56:1523-1529. [PMID: 20451528 DOI: 10.1016/j.jinsphys.2010.04.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2009] [Revised: 04/28/2010] [Accepted: 04/30/2010] [Indexed: 05/29/2023]
Abstract
Testes size often predicts the winner during episodes of sperm competition. However, little is known about the source of nutrients allocated to testes development, or testes plasticity under varying nutrient availability. Among many holometabolous insects, metabolic resources can derive from the larval or adult diet. Distinguishing the source of nutrients allocated to testes can shed light on life history factors (such as maternal influences) that shape the evolution of male reproductive strategies. Here we used an experimental approach to assess resource allocation to testes development in walnut flies (Rhagoletis juglandis) from differing nutritional backgrounds. We fed adult male walnut flies on sugar and yeast diets that contrasted with the larval diet in carbon and nitrogen stable isotope ratios. This design allowed us to assess the dietary source of testes carbon and nitrogen and its change over time. We found significant incorporation of adult dietary carbon into testes, implying that walnut flies are income breeders for carbon (relying more on adult resources). In contrast, we found little evidence that walnut flies incorporate adult dietary nitrogen into testes development. We discuss the implications of these allocation decisions for life history evolution in this species.
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36
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Does it pay to delay? Flesh flies show adaptive plasticity in reproductive timing. Oecologia 2010; 165:311-20. [PMID: 20953961 DOI: 10.1007/s00442-010-1805-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 09/23/2010] [Indexed: 10/18/2022]
Abstract
Life-history plasticity is widespread among organisms. However, an important question is whether it is adaptive. Most models for plasticity in life-history timing predict that animals, once they have reached the minimal nutritional threshold under poor conditions, will accelerate development or time to reproduction. Adaptive delays in reproduction are not common, especially in short-lived species. Examples of adaptive reproductive delays exist in mammalian populations experiencing strong interspecific (e.g., predation) and intraspecific (e.g., infanticide) competition. But are there other environmental factors that may trigger an adaptive delay in reproductive timing? We show that the short-lived flesh fly Sarcophaga crassipalpis will delay reproduction under nutrient-poor conditions, even though it has already met the minimal nutritional threshold for reproduction. We test whether this delay strategy is an adaptive response allowing the scavenger time to locate more resources by experimentally providing supplemental protein pulses (early, mid and late) throughout the reproductive delay period. Flies receiving additional protein produced more and larger eggs, demonstrating a benefit of the delay. In addition, by tracking the allocation of carbon from the pulses using stable isotopes, we show that flies receiving earlier pulses incorporated more carbon into eggs and somatic tissue than those given a later pulse. These results indicate that the reproductive delay in S. crassipalpis is consistent with adaptive post-threshold plasticity, a nutritionally linked reproductive strategy that has not been reported previously in an invertebrate species.
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37
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Warne RW, Gilman CA, Wolf BO. Tissue-carbon incorporation rates in lizards: implications for ecological studies using stable isotopes in terrestrial ectotherms. Physiol Biochem Zool 2010; 83:608-17. [PMID: 20441446 DOI: 10.1086/651585] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Carbon stable isotope (delta(13)C) analysis can be used to infer the origin and to estimate the flow of nutrient resources through animals and across ecological compartments. These applications require knowledge of the rates at which carbon is incorporated into animal tissues and diet-to-tissue discrimination factors (Delta(13)C). Studies of carbon dynamics in terrestrial vertebrates to date have focused almost solely on endothermic animals; ectotherms such as reptiles have received little attention. Here we determined carbon incorporation rates and Delta(13)C in tissues of prairie lizards (Sceloporus undulatus consobrinus) and collared lizards (Crotaphytus collaris). The smaller lizard, S. undulatus, had carbon retention times of 25 and 61 d in plasma and red blood cells (RBC), respectively, compared with 44 and 311 d for the larger C. collaris. Liver, muscle, and skin carbon retention times for S. undulatus were 21, 81, and 94 d. Growth contributed 9%-19% of the carbon incorporated into these tissues. This contribution is similar to endotherms measured at comparable developmental stages. Mean Delta(13)C for plasma (-0.2 per thousand +/- 0.4 per thousand Vienna Pee Dee Belemnite Standard) and RBCs (-1.3 per thousand +/- 0.8 per thousand) were similar to values reported for other vertebrates. Carbon incorporation rates for these ectotherms, however, are seven times slower than in similarly sized adult endotherms. Although a limited comparison with data for warm-water fishes suggests comparable incorporation rates between aquatic and terrestrial ectotherms, this study highlights the lack of experimental data for isotope dynamics in ectotherms across a range of temperatures, body sizes, and developmental stages.
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Affiliation(s)
- Robin W Warne
- Biology Department, University of New Mexico, Albuquerque, NM 87131-0001, USA.
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Wessels FJ, Jordan DC, Hahn DA. Allocation from capital and income sources to reproduction shift from first to second clutch in the flesh fly, Sarcophaga crassipalpis. JOURNAL OF INSECT PHYSIOLOGY 2010; 56:1269-1274. [PMID: 20417214 DOI: 10.1016/j.jinsphys.2010.03.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 03/26/2010] [Accepted: 03/31/2010] [Indexed: 05/29/2023]
Abstract
Understanding how resources are allocated between survival and reproduction is fundamental to the study of the evolution of life histories. Reproductive resources can come from two intrinsic resource pools, stored reserves (capital) acquired before reproduction or income acquired during reproduction. The variety of reproductive strategies in insects is remarkable and reproductive allocation encompasses the complete range of allocation strategies from pure capital breeders to pure income breeders. However, most organisms probably use a blend of capital and income and this blend is likely dynamic, changing between reproductive bouts in response to internal and external conditions. We used stable isotopes to quantify the allocation of capital and income resources to reproduction in the flesh fly, Sarcopha crassipalpis and assessed how allocation patterns change over multiple bouts of reproduction. Sarcophaga crassipalpis shifts from a slight investment of capital in the first clutch to an almost pure income breeder in the second clutch. We discuss the relationship between activity and allocation, and the potential for this system to understand how allocation patterns change in response to environmental stress.
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Affiliation(s)
- Frank J Wessels
- University of Florida, Entomology and Nematology Dept., Gainesville, FL 32611, USA.
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Judd ET, Hatle JD, Drewry MD, Wessels FJ, Hahn DA. Allocation of nutrients to somatic tissues in young ovariectomized grasshoppers. Integr Comp Biol 2010; 50:818-28. [PMID: 21558244 DOI: 10.1093/icb/icq105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The disposable soma hypothesis predicts that when reproduction is reduced, life span is increased because more nutrients are invested in the soma, increasing somatic repair. Rigorously testing the hypothesis requires tracking nutrients from ingestion to allocation to the soma or to reproduction. Fruit flies on life-extending dietary restriction increase allocation to the soma "relative" to reproduction, suggesting that allocation of nutrients can be associated with extension of life span. Here, we use stable isotopes to track ingested nutrients in ovariectomized grasshoppers during the first oviposition cycle. Previous work has shown that ovariectomy extends life span, but investment of protein in reproduction is not reduced until after the first clutch of eggs is laid. Because ovariectomy does not affect investment in reproduction at this age, the disposable soma hypothesis would predict that ovariectomy should also not affect investment in somatic tissues. We developed grasshopper diets with distinct signatures of ¹³C and ¹⁵N, but that produced equivalent reproductive outputs. These diets are, therefore, appropriate for the reciprocal switches in diet needed for tracking ingested nutrients. Incorporation of stable isotopes into eggs showed that grasshoppers are income breeders, especially for carbon. Allocation to the fat body of nitrogen ingested as adults was slightly increased by ovariectomy; this was our only result that was not consistent with the disposable soma hypothesis. In contrast, ovariectomy did not affect allocation of nitrogen to femoral muscles. Further, allocation of carbon to the fat body or femoral muscles did not appear to be affected by ovariectomy. Total anti-oxidant activities in the hemolymph and femoral muscles were not affected by ovariectomy. These experiments showed that allocation of nutrients was altered little by ovariectomy in young grasshoppers. Additional studies on older individuals are needed to further test the disposable soma hypothesis.
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Affiliation(s)
- Evan T Judd
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, Florida 32224, USA
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Wessels FJ, Hahn DA. Carbon 13 discrimination during lipid biosynthesis varies with dietary concentration of stable isotopes: implications for stable isotope analyses. Funct Ecol 2010. [DOI: 10.1111/j.1365-2435.2010.01716.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Oppel S, Powell AN, O'Brien DM. King eiders use an income strategy for egg production: a case study for incorporating individual dietary variation into nutrient allocation research. Oecologia 2010; 164:1-12. [PMID: 20364389 DOI: 10.1007/s00442-010-1619-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Accepted: 03/15/2010] [Indexed: 11/30/2022]
Abstract
The use of stored nutrients for reproduction represents an important component of life-history variation. Recent studies from several species have used stable isotopes to estimate the reliance on stored body reserves in reproduction. Such approaches rely on population-level dietary endpoints to characterize stored reserves ("capital") and current diet ("income"). Individual variation in diet choice has so far not been incorporated in such approaches, but is crucial for assessing variation in nutrient allocation strategies. We investigated nutrient allocation to egg production in a large-bodied sea duck in northern Alaska, the king eider (Somateria spectabilis). We first used Bayesian isotopic mixing models to quantify at the population level the amount of endogenous carbon and nitrogen invested into egg proteins based on carbon and nitrogen isotope ratios. We then defined the isotopic signature of the current diet of every nesting female based on isotope ratios of eggshell membranes, because diets varied isotopically among individual king eiders on breeding grounds. We used these individual-based dietary isotope signals to characterize nutrient allocation for each female in the study population. At the population level, the Bayesian and the individual-based approaches yielded identical results, and showed that king eiders used an income strategy for the synthesis of egg proteins. The majority of the carbon and nitrogen in albumen (C: 86 +/- 18%, N: 99 +/- 1%) and the nitrogen in lipid-free yolk (90 +/- 15%) were derived from food consumed on breeding grounds. Carbon in lipid-free yolk derived evenly from endogenous sources and current diet (exogenous C: 54 +/- 24%), but source contribution was highly variable among individual females. These results suggest that even large-bodied birds traditionally viewed as capital breeders use exogenous nutrients for reproduction. We recommend that investigations of nutrient allocation should incorporate individual variation into mixing models to reveal intraspecific variation in reproductive strategies.
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Affiliation(s)
- Steffen Oppel
- Department of Biology and Wildlife, University of Alaska, 211 Irving 1, Fairbanks, AK 99775-6100, USA.
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Foster S. Sugar feeding via trehalose haemolymph concentration affects sex pheromone production in mated Heliothis virescens moths. J Exp Biol 2009; 212:2789-94. [DOI: 10.1242/jeb.030676] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Long-distance, female-produced sex pheromones are widespread among moths. Larval feeding provides most of the nutrients for development of these insects but is not thought to influence the de novo production of the fatty-acid derived compounds used as pheromones by most species. Feeding on plant nectar (sugar) by adult moths is important for increasing female fitness and also for the pollination of many plant species. In this paper, I show that feeding on sucrose solution, as opposed to water, increases sex pheromone titre in mated, but not virgin, female Heliothis virescens. Mating caused a rapid decrease in haemolymph trehalose concentration, which was restored to near-virgin levels by sugar ingestion. When isolated mated female abdomens were cultured with different concentrations of trehalose, pheromone titre increased with increasing trehalose concentration. This effect was not observed when abdomens were cultured on saline containing the sugar rhamnose,which insects cannot metabolise to glucose. Virgins injected with the juvenile hormone (JH) analogue, methoprene, showed the same effects as mated females with respect to pheromone titre and haemolymph trehalose concentration. Thus,following mating increases in JH titre increase demand for, and lowering of,blood sugar to develop oocytes, which can be compensated for by sugar ingestion. Haemolymph trehalose concentration probably influences glycolysis in gland cells and, consequently, levels of cytosolic citrate and acetyl-CoA for pheromone biosynthesis. This increase in pheromone titre in sugar-fed,mated females may facilitate further mating and increased fecundity. Thus,exogenous sugar feeding is behaviourally and physiologically integrated with endogenous JH titre to maximise female fitness.
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Affiliation(s)
- Stephen Foster
- Entomology Department, North Dakota State University, PO Box 6050, Fargo,ND 58108, USA
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Larsen T, Ventura M, Damgaard C, Hobbie EA, Krogh PH. Nutrient allocations and metabolism in two collembolans with contrasting reproduction and growth strategies. Funct Ecol 2009. [DOI: 10.1111/j.1365-2435.2009.01564.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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del Rio CM, Wolf N, Carleton SA, Gannes LZ. Isotopic ecology ten years after a call for more laboratory experiments. Biol Rev Camb Philos Soc 2008; 84:91-111. [PMID: 19046398 DOI: 10.1111/j.1469-185x.2008.00064.x] [Citation(s) in RCA: 420] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
About 10 years ago, reviews of the use of stable isotopes in animal ecology predicted explosive growth in this field and called for laboratory experiments to provide a mechanistic foundation to this growth. They identified four major areas of inquiry: (1) the dynamics of isotopic incorporation, (2) mixing models, (3) the problem of routing, and (4) trophic discrimination factors. Because these areas remain central to isotopic ecology, we use them as organising foci to review the experimental results that isotopic ecologists have collected in the intervening 10 years since the call for laboratory experiments. We also review the models that have been built to explain and organise experimental results in these areas.
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Barboza P, Parker K. Allocating Protein to Reproduction in Arctic Reindeer and Caribou. Physiol Biochem Zool 2008; 81:835-55. [DOI: 10.1086/590414] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Warner DA, Bonnet X, Hobson KA, Shine R. Lizards combine stored energy and recently acquired nutrients flexibly to fuel reproduction. J Anim Ecol 2008; 77:1242-9. [PMID: 18637855 DOI: 10.1111/j.1365-2656.2008.01442.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1. Energy allocation strategies for reproduction are viewed typically as a continuum between reliance on 'income' (recently acquired energy) vs. 'capital' (stored reserves) for fuelling reproduction. Because ectothermy facilitates long-term energy storage and often involves low feeding rates, traditional views suggest that many ectotherms rely heavily on stored reserves for egg production. 2. We explored the temporal relationship between energy intake and expenditure in a multi-clutching lizard (Amphibolurus muricatus) by evaluating the effect of maternal nutrition on reproductive output and by contrasting delta(13)C measurements of the maternal diet and endogenous energy stores with that of the eggs produced. 3. Our experiment revealed that females utilize both endogenous energy stores and recently acquired food to fuel reproduction; this pattern did not shift seasonally from first to second clutches produced. Importantly, however, egg lipid was derived primarily from capital, whereas egg protein was derived about equally from both income and capital. 4. Overall, these results suggest that the energy allocation strategy used for reproduction differs among egg components, and that the use of recently acquired energy for reproduction may be more widespread in ectotherms than thought previously.
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Affiliation(s)
- Daniel A Warner
- School of Biological Sciences, University of Sydney, New South Wales, Australia.
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Beyond the reaction progress variable: the meaning and significance of isotopic incorporation data. Oecologia 2008; 156:765-72. [PMID: 18446374 DOI: 10.1007/s00442-008-1040-z] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Accepted: 03/26/2008] [Indexed: 10/22/2022]
Abstract
Ecologists conduct isotopic incorporation experiments to determine the residence time of various stable isotopes in animal tissues. These experiments permit determining the time window through which isotopic ecologists perceive the course of diet changes, and therefore the scale of the inferences that we can make from isotopic data. Until recently, the results of these experiments were analyzed using first-order, one-compartment models. Cerling et al. (Oecologia 151:175-189, 2007) proposed an approach they named the reaction progress variable to: (1) determine how many compartments are needed to describe a pattern of istopic incorporation, and (2) to estimate the size and rate constant of each pool. We elaborate on the approach described by Cerling et al. (Oecologia 151:175-189, 2007) by providing a way to estimate average retention times for an isotope in a tissue (and its associate error) for multi-compartment models. We also qualify the interpretation of the parameters in multi-compartment models by showing that many possible mechanisms yield models with the same functional form. Multi-compartment models are phenomenological, rather than mechanistic descriptions, of incorporation data. Finally, we propose the use of information theoretic criteria to assess the number of compartments that must be included in models of isotopic incorporation.
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Welch KC, Herrera M. LG, Suarez RK. Dietary sugar as a direct fuel for flight in the nectarivorous bat Glossophaga soricina. J Exp Biol 2008; 211:310-6. [DOI: 10.1242/jeb.012252] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
It is thought that the capacity of mammals to directly supply the energetic needs of exercising muscles using recently ingested fuels is limited. Humans,for example, can only fuel about 30%, at most, of exercise metabolism with dietary sugar. Using indirect calorimetry, i.e. measurement of rates of O2 consumption and CO2 production, in combination with carbon stable isotope techniques, we found that nectarivorous bats Glossophaga soricina use recently ingested sugars to provide ∼78%of the fuel required for oxidative metabolism during their energetically expensive hovering flight. Among vertebrate animals, only hummingbirds exceed the capacity of these nectarivorous bats to fuel exercise with dietary sucrose. Similar experiments performed on Anna's (Calypte anna) and rufous (Selasphorus rufus) hummingbirds show that they use recently ingested sugars to support ∼95% of hovering metabolism. These results support the suggestion that convergent evolution of physiological and biochemical traits has occurred among hovering nectarivorous animals,rendering them capable of a process analogous to aerial refueling in aircraft.
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Affiliation(s)
- Kenneth C. Welch
- Department of Ecology, Evolution and Marine Biology, University of California,Santa Barbara, CA 93106-9610, USA
| | - L. Gerardo Herrera M.
- Estación de Biología de Chamela, Instituto de Biología,Universidad Nacional Autónoma de México, Apartado Postal 21,48980, San Patricio, Jalisco, México
| | - Raul K. Suarez
- Department of Ecology, Evolution and Marine Biology, University of California,Santa Barbara, CA 93106-9610, USA
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