1
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Steurer M, Ruther J, Pokorny T. Behavioural consequences of intraspecific variability in a mate recognition signal. Proc Biol Sci 2024; 291:20232518. [PMID: 38444335 PMCID: PMC10915540 DOI: 10.1098/rspb.2023.2518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 02/08/2024] [Indexed: 03/07/2024] Open
Abstract
Mate recognition is paramount for sexually reproducing animals, and many insects rely on cuticular hydrocarbons (CHCs) for close-range sexual communication. To ensure reliable mate recognition, intraspecific sex pheromone variability should be low. However, CHCs can be influenced by several factors, with the resulting variability potentially impacting sexual communication. While intraspecific CHC variability is a common phenomenon, the consequences thereof for mate recognition remain largely unknown. We investigated the effect of CHC variability on male responses in a parasitoid wasp showing a clear-cut within-population CHC polymorphism (three distinct female chemotypes, one thereof similar to male profiles). Males clearly discriminated between female and male CHCs, but not between female chemotypes in no-choice assays. When given a choice, a preference hierarchy emerged. Interestingly, the most attractive chemotype was the one most similar to male profiles. Mixtures of female CHCs were as attractive as chemotype-pure ones, while a female-male mixture negatively impacted male responses, indicating assessment of the entire, complex CHC profile composition. Our study reveals that the evaluation of CHC profiles can be strict towards 'undesirable' features, but simultaneously tolerant enough to cover a range of variants. This reconciles reliable mate recognition with naturally occurring variability.
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Affiliation(s)
- Maximilian Steurer
- Institute of Zoology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Joachim Ruther
- Institute of Zoology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Tamara Pokorny
- Institute of Zoology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
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2
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Risely A, Byrne PG, Hoye BJ, Silla AJ. Dietary carotenoid supplementation has long-term and community-wide effects on the amphibian skin microbiome. Mol Ecol 2024; 33:e17203. [PMID: 37962103 DOI: 10.1111/mec.17203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 08/24/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023]
Abstract
The amphibian skin microbiome plays a crucial role in host immunity and pathogen defence, yet we know little about the environmental drivers of skin microbial variation across host individuals. Inter-individual variation in the availability of micro-nutrients such as dietary carotenoids, which are involved in amphibian immunity, may be one factor that influences skin microbial assembly across different life history stages. We compared the effect of four carotenoid supplementation regimes during different life stages on the adult skin microbiome using a captive population of the critically endangered southern corroboree frog, Pseudophryne corroboree. We applied 16S rRNA sequencing paired with joint-species distribution models to examine the effect of supplementation on taxon abundances. We found that carotenoid supplementation had subtle yet taxonomically widespread effects on the skin microbiome, even 4.5 years post supplementation. Supplementation during any life-history stage tended to have a positive effect on the number of bacterial taxa detected, although explanatory power was low. Some genera were sensitive to supplementation pre-metamorphosis, but most demonstrated either additive or dominant effects, whereby supplementation during one life history stage had intermediate or similar effects, respectively, to supplementation across life. Carotenoid supplementation increased abundances of taxa belonging to lactic acid bacteria, including Lactococcus and Enterococcus, a group of bacteria that have previously been linked to protection against the amphibian fungal pathogen Batrachochytrium dendrobatidis (Bd). While the fitness benefits of these microbial shifts require further study, these results suggest a fundamental relationship between nutrition and the amphibian skin microbiome which may be critical to amphibian health and the development of novel conservation strategies.
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Affiliation(s)
- A Risely
- School of Science, Engineering and Environment, Salford University, Manchester, UK
| | - Phillip G Byrne
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales, Australia
| | - Bethany J Hoye
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales, Australia
| | - Aimee J Silla
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales, Australia
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3
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Ježová Z, Prokop P, Zvaríková M, Zvarík M. Unraveling the Significance of Draglines: Female Sexual Signalization in the Nursery-Web Spider, Pisaura mirabilis. INSECTS 2023; 14:765. [PMID: 37754733 PMCID: PMC10532251 DOI: 10.3390/insects14090765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/06/2023] [Accepted: 09/11/2023] [Indexed: 09/28/2023]
Abstract
Chemical signals used by animals to attract the opposite sex are well known in insects, but heavily understudied in spiders. We investigated the role of chemical signals in female draglines in a gift-giving spider, Pisaura mirabilis, using combined data from behavioral tests and high-performance liquid chromatography (HPLC). We also investigated whether the quality of sexual signalization is influenced by crucial factors, such as female spider ontogeny, nutritional status, and mating status. We found that draglines of adult (versus subadult) and hungry (versus fed) females stimulated male motivation to produce nuptial gift, and highly sexually excited males invested more silk in gift production than less sexually excited males. Unexpectedly, chemical signals of eggsac-carrying females were similarly sexually attractive to draglines of adult females not carrying eggsac. HPLC identified significant chemical differences in female draglines, but these differences did not always correspond to male behavior. The integration of behavioral and chemical approaches is required to better understand animal behavior in future research.
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Affiliation(s)
- Zuzana Ježová
- Department of Environmental Ecology and Landscape Management, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (Z.J.)
| | - Pavol Prokop
- Department of Environmental Ecology and Landscape Management, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (Z.J.)
- Institute of Zoology, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 06 Bratislava, Slovakia
| | - Martina Zvaríková
- Department of Environmental Ecology and Landscape Management, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (Z.J.)
| | - Milan Zvarík
- Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská Dolina F1, 842 48 Bratislava, Slovakia;
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4
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Henneken J, Blamires SJ, Goodger JQ, Jones TM, Elgar MA. Population level variation in silk chemistry but not web architecture in a widely distributed orb web spider. Biol J Linn Soc Lond 2022. [DOI: 10.1093/biolinnean/blac089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Spider webs are iconic examples of extended phenotypes that are remarkably plastic across different environments. Orb webs are not only effective traps for capturing prey, but can also provide information to potential mates and, in some cases, potential predators and prey through silk-based chemicals. As with regular phenotypic traits, variability in the properties of spider webs is thought to be mediated by a combination of genetic and environmental effects. Here, we examined variation in several key features of the webs of the orb-weaving spider Argiope keyserlingi across five geographically disparate populations. We documented variation in web architecture and chemical properties of webs collected directly from the field. We then probed the potential for the underlying environmental driver of local insect abundance to explain this variation, by analysing the properties of orb webs constructed by the spiders from these different populations, but under identical laboratory conditions. We found no evidence of variation across populations in the architecture of webs constructed in the laboratory, despite the large geographic distances. Nonetheless, we discovered between population variation in the composition of chemicals found on the surface of silk and in the taxonomic distribution of available prey. Furthermore, there was a positive correlation between the quantity of nitrogenous compounds in web silks and female body condition. When combined, these findings suggest that environmental mechanisms can drive variation in web traits across spider populations.
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Affiliation(s)
- Jessica Henneken
- School of BioSciences, The University of Melbourne , VIC 3010 , Australia
- Agriculture Victoria Research, AgriBio Centre , 5 Ring Road Bundoora, VIC 3083 , Australia
| | - Sean J Blamires
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, The University of New South Wales , Sydney, NSW 2052 , Australia
- NMR Facility, Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW 2052 , Australia
| | - Jason Qd Goodger
- School of Ecosystem and Forest Sciences, The University of Melbourne, VIC 3010 , Australia
| | - Therésa M Jones
- School of BioSciences, The University of Melbourne , VIC 3010 , Australia
| | - Mark A Elgar
- School of BioSciences, The University of Melbourne , VIC 3010 , Australia
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5
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Iglesias-Carrasco M, Wong BBM, Jennions MD. In the shadows: wildlife behaviour in tree plantations. Trends Ecol Evol 2022; 37:838-850. [PMID: 35710479 DOI: 10.1016/j.tree.2022.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 05/17/2022] [Accepted: 05/20/2022] [Indexed: 10/18/2022]
Abstract
Destruction of natural habitats for tree plantations is a major threat to wildlife. These novel environments elicit behavioural changes that can either be detrimental or beneficial to survival and reproduction, with population - and community - level consequences. However, compared with well-documented changes following other forms of habitat modification, we know little about wildlife behavioural responses to tree plantations, and even less about their associated fitness costs. Here, we highlight critical knowledge gaps in understanding the ecological and evolutionary consequences of behavioural shifts caused by tree plantations and discuss how wildlife responses to plantations could be critical in determining which species persist in these highly modified environments.
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6
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Pham HT, Elgar MA, van Lieshout E, McNamara KB. Experimental immune challenges reduce the quality of male antennae and female pheromone output. Sci Rep 2022; 12:3578. [PMID: 35246550 PMCID: PMC8897396 DOI: 10.1038/s41598-022-07100-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 02/01/2022] [Indexed: 11/17/2022] Open
Abstract
Sexual signalling is a key feature of reproductive investment, yet the effects of immune system activation on investment into chemical signalling, and especially signal receiver traits such as antennae, are poorly understood. We explore how upregulation of juvenile immunity affects male antennal functional morphology and female pheromone attractiveness in the gumleaf skeletonizer moth, Uraba lugens. We injected final-instar larvae with a high or low dose of an immune elicitor or a control solution and measured male antennal morphological traits, gonad investment and female pheromone attractiveness. Immune activation affected male and female signalling investment: immune challenged males had a lower density of antennal sensilla, and the pheromone of immune-challenged females was less attractive to males than their unchallenged counterparts. Immune challenge affected female investment into ovary development but not in a linear, dose-dependent manner. While there was no effect of immune challenge on testes size, there was a trade-off between male pre- and post-copulatory investment: male antennal length was negatively correlated with testes size. Our study highlights the costs of elaborate antennae and pheromone production and demonstrates the capacity for honest signalling in species where the costs of pheromone production were presumed to be trivial.
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Affiliation(s)
- Hieu T Pham
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia.,Department of Entomology, Faculty of Agronomy, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - Mark A Elgar
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Emile van Lieshout
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Kathryn B McNamara
- School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia.
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7
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Improving Natural Enemy Selection in Biological Control through Greater Attention to Chemical Ecology and Host-Associated Differentiation of Target Arthropod Pests. INSECTS 2022; 13:insects13020160. [PMID: 35206733 PMCID: PMC8877252 DOI: 10.3390/insects13020160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/28/2022] [Accepted: 01/31/2022] [Indexed: 12/04/2022]
Abstract
Host-associated differentiation (HAD) refers to cases in which genetically distinct populations of a species (e.g., herbivores or natural enemies) preferentially reproduce or feed on different host species. In agroecosystems, HAD often results in unique strains or biotypes of pest species, each attacking different species of crops. However, HAD is not restricted to pest populations, and may cascade to the third trophic level, affecting host selection by natural enemies, and ultimately leading to HAD within natural enemy species. Natural enemy HAD may affect the outcomes of biological control efforts, whether classical, conservation, or augmentative. Here, we explore the potential effects of pest and natural enemy HAD on biological control in agroecosystems, with emphases on current knowledge gaps and implications of HAD for selection of biological control agents. Additionally, given the importance of semiochemicals in mediating interactions between trophic levels, we emphasize the role of chemical ecology in interactions between pests and natural enemies, and suggest areas of consideration for biological control. Overall, we aim to jump-start a conversation concerning the relevance of HAD in biological control by reviewing currently available information on natural enemy HAD, identifying challenges to incorporating HAD considerations into biological control efforts, and proposing future research directions on natural enemy selection and HAD.
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8
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García‐Roa R, Domínguez‐Santos R, Pérez‐Brocal V, Moya A, Latorre A, Carazo P. Kin recognition in
Drosophila
: rearing environment and relatedness can modulate gut microbiota and cuticular hydrocarbon odour profiles. OIKOS 2022. [DOI: 10.1111/oik.08755] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Roberto García‐Roa
- Ethology Lab, Cavanilles Inst. of Biodiversity and Evolutionary Biology, Univ. of Valencia Valencia Spain
| | | | - Vicente Pérez‐Brocal
- Foundation for the Promotion of Sanitary and Biomedical Research of Valencia Region (FISABIO) – Public Health Valencia Spain
- CIBER of Epidemiology and Public Health (CIBERESP) Madrid Spain
| | - Andrés Moya
- Inst. for Integrative Systems Biology, Univ. of Valencia – CSIC Valencia Spain
- Foundation for the Promotion of Sanitary and Biomedical Research of Valencia Region (FISABIO) – Public Health Valencia Spain
| | - Amparo Latorre
- Inst. for Integrative Systems Biology, Univ. of Valencia – CSIC Valencia Spain
- Foundation for the Promotion of Sanitary and Biomedical Research of Valencia Region (FISABIO) – Public Health Valencia Spain
| | - Pau Carazo
- Ethology Lab, Cavanilles Inst. of Biodiversity and Evolutionary Biology, Univ. of Valencia Valencia Spain
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9
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Zeeman AN, Smallegange IM, Steel EB, Groot AT, Stewart KA. Toward an understanding of the chemical ecology of alternative reproductive tactics in the bulb mite (Rhizoglyphus robini). BMC Ecol Evol 2022; 22:5. [PMID: 34998364 PMCID: PMC8742560 DOI: 10.1186/s12862-021-01956-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 12/22/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Under strong sexual selection, certain species evolve distinct intrasexual, alternative reproductive tactics (ARTs). In many cases, ARTs can be viewed as environmentally-cued threshold traits, such that ARTs coexist if their relative fitness alternates over the environmental cue gradient. Surprisingly, the chemical ecology of ARTs has been underexplored in this context. To our knowledge, no prior study has directly quantified pheromone production for ARTs in a male-polymorphic species. Here, we used the bulb mite-in which males are either armed fighters that kill conspecifics, or unarmed scramblers (which have occasionally been observed to induce mating behavior in other males)-as a model system to gain insight into the role of pheromones in the evolutionary maintenance of ARTs. Given that scramblers forgo investment into weaponry, we tested whether scramblers produce higher quantities of the putative female sex-pheromone α-acaridial than fighters, which would improve the fitness of the scrambler phenotype through female mimicry by allowing avoidance of aggression from competitors. To this end, we sampled mites from a rich and a poor nutritional environment and quantified their production of α-acaridial through gas chromatography analysis. RESULTS We found a positive relationship between pheromone production and body size, but males exhibited a steeper slope in pheromone production with increasing size than females. Females exhibited a higher average pheromone production than males. We found no significant difference in slope of pheromone production over body size between fighters and scramblers. However, scramblers reached larger body sizes and higher pheromone production than fighters, providing some evidence for a potential female mimic strategy adopted by large scramblers. Pheromone production was significantly higher in mites from the rich nutritional environment than the poor environment. CONCLUSION Further elucidation of pheromone functionality in bulb mites, and additional inter- and intrasexual comparisons of pheromone profiles are needed to determine if the observed intersexual and intrasexual differences in pheromone production are adaptive, if they are a by-product of allometric scaling, or diet-mediated pheromone production under weak selection. We argue chemical ecology offers a novel perspective for research on ARTs and other complex life-history traits.
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Affiliation(s)
- Adam N Zeeman
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Isabel M Smallegange
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Emily Burdfield Steel
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Astrid T Groot
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Kathryn A Stewart
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands.
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands.
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10
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Zweerus NL, van Wijk M, Schal C, Groot AT. Experimental evidence for female mate choice in a noctuid moth. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.06.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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11
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Scolari F, Valerio F, Benelli G, Papadopoulos NT, Vaníčková L. Tephritid Fruit Fly Semiochemicals: Current Knowledge and Future Perspectives. INSECTS 2021; 12:insects12050408. [PMID: 33946603 PMCID: PMC8147262 DOI: 10.3390/insects12050408] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 04/23/2021] [Accepted: 04/27/2021] [Indexed: 12/14/2022]
Abstract
The Dipteran family Tephritidae (true fruit flies) comprises more than 5000 species classified in 500 genera distributed worldwide. Tephritidae include devastating agricultural pests and highly invasive species whose spread is currently facilitated by globalization, international trade and human mobility. The ability to identify and exploit a wide range of host plants for oviposition, as well as effective and diversified reproductive strategies, are among the key features supporting tephritid biological success. Intraspecific communication involves the exchange of a complex set of sensory cues that are species- and sex-specific. Chemical signals, which are standing out in tephritid communication, comprise long-distance pheromones emitted by one or both sexes, cuticular hydrocarbons with limited volatility deposited on the surrounding substrate or on the insect body regulating medium- to short-distance communication, and host-marking compounds deposited on the fruit after oviposition. In this review, the current knowledge on tephritid chemical communication was analysed with a special emphasis on fruit fly pest species belonging to the Anastrepha, Bactrocera, Ceratitis, and Rhagoletis genera. The multidisciplinary approaches adopted for characterising tephritid semiochemicals, and the real-world applications and challenges for Integrated Pest Management (IPM) and biological control strategies are critically discussed. Future perspectives for targeted research on fruit fly chemical communication are highlighted.
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Affiliation(s)
- Francesca Scolari
- Institute of Molecular Genetics IGM-CNR “Luigi Luca Cavalli-Sforza”, I-27100 Pavia, Italy
- Correspondence: (F.S.); (L.V.); Tel.: +39-0382-986421 (F.S.); +420-732-852-528 (L.V.)
| | - Federica Valerio
- Department of Biology and Biotechnology, University of Pavia, I-27100 Pavia, Italy;
| | - Giovanni Benelli
- Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy;
| | - Nikos T. Papadopoulos
- Department of Agriculture Crop Production and Rural Environment, University of Thessaly, Fytokou st., N. Ionia, 38446 Volos, Greece;
| | - Lucie Vaníčková
- Department of Chemistry and Biochemistry, Faculty of AgriSciences Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
- Correspondence: (F.S.); (L.V.); Tel.: +39-0382-986421 (F.S.); +420-732-852-528 (L.V.)
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12
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McLean S, Nichols DS, Davies NW. Volatile scent chemicals in the urine of the red fox, Vulpes vulpes. PLoS One 2021; 16:e0248961. [PMID: 33784329 PMCID: PMC8009367 DOI: 10.1371/journal.pone.0248961] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 03/08/2021] [Indexed: 11/20/2022] Open
Abstract
The red fox is a highly adaptable mammal that has established itself world-wide in many different environments. Contributing to its success is a social structure based on chemical signalling between individuals. Urine scent marking behaviour has long been known in foxes, but there has not been a recent study of the chemical composition of fox urine. We have used solid-phase microextraction and gas chromatography-mass spectrometry to analyze the urinary volatiles in 15 free-ranging wild foxes (2 female) living in farmlands and bush in Victoria, Australia. Foxes here are routinely culled as feral pests, and the urine was collected by bladder puncture soon after death. Compounds were identified from their mass spectra and Kovats retention indices. There were 53 possible endogenous scent compounds, 10 plant-derived compounds and 5 anthropogenic xenobiotics. Among the plant chemicals were several aromatic apocarotenoids previously found in greater abundance in the fox tail gland. They reflect the dietary consumption of carotenoids, essential for optimal health. One third of all the endogenous volatiles were sulfur compounds, a highly odiferous group which included thiols, methylsulfides and polysulfides. Five of the sulfur compounds (3-isopentenyl thiol, 1- and 2-phenylethyl methyl sulfide, octanethiol and benzyl methyl sulfide) have only been found in foxes, and four others (isopentyl methyl sulfide, 3-isopentenyl methyl sulfide, and 1- and 2-phenylethane thiol) only in some canid, mink and skunk species. This indicates that they are not normal mammalian metabolites and have evolved to serve a specific role. This role is for defence in musteloids and most likely for chemical communication in canids. The total production of sulfur compounds varied greatly between foxes (median 1.2, range 0.4–32.3 μg ‘acetophenone equivalents’/mg creatinine) as did the relative abundance of different chemical types. The urinary scent chemistry may represent a highly evolved system of semiochemicals for communication between foxes.
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Affiliation(s)
- Stuart McLean
- School of Pharmacy and Pharmacology, University of Tasmania, Hobart, Tasmania, Australia
- * E-mail:
| | - David S. Nichols
- Central Science Laboratory, University of Tasmania, Hobart, Tasmania, Australia
| | - Noel W. Davies
- Central Science Laboratory, University of Tasmania, Hobart, Tasmania, Australia
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13
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Poirier AC, Waterhouse JS, Watsa M, Erkenswick GA, Moreira LAA, Tang J, Dunn JC, Melin AD, Smith AC. On the trail of primate scent signals: A field analysis of callitrichid scent-gland secretions by portable gas chromatography-mass spectrometry. Am J Primatol 2021; 83:e23236. [PMID: 33534928 DOI: 10.1002/ajp.23236] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 11/23/2020] [Accepted: 01/15/2021] [Indexed: 12/15/2022]
Abstract
Chemosignals are mediators of social interactions in mammals, providing con- and hetero-specifics with information on fixed (e.g., species, sex, group, and individual identity) and variable (e.g., social, reproductive, and health status) features of the signaler. Yet, methodological difficulties of recording and quantifying odor signals, especially in field conditions, have hampered studies of natural systems. We present the first use of the Torion® portable gas chromatography-mass spectrometry (GC-MS) instrument for in situ chemical analysis of primate scents. We collected and analyzed swab samples from the scent glands and skin from 13 groups (57 individuals) of two sympatric species of wild emperor tamarins, Saguinus imperator, and Weddell's saddleback tamarins, Leontocebus weddelli (Callitrichidae). In total, 11 compounds of interest (i.e., probably derived from the animals) could be detected in the samples, with 31 of 215 samples containing at least one compound of interest. The composition of these 31 samples varied systematically with species, group, sex, and breeding status. Moreover, we tentatively identified seven of the compounds of interest as methyl hexanoate, benzaldehyde, ethyl hexanoate, acetophenone, a branched C15 alkane, 4-methoxybenzaldehyde, and hexadecan-1-ol. As the field of primate semiochemistry continues to grow, we believe that portable GC-MS instruments have the potential to help make progress in the study of primate chemosignaling in field conditions, despite limitations that we encountered. We further provide recommendations for future use of the Torion® portable GC-MS for in situ analyses.
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Affiliation(s)
- Alice C Poirier
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Canada.,School of Life Sciences, Anglia Ruskin University, Cambridge, UK
| | | | - Mrinalini Watsa
- Population Sustainability, Institute for Conservation Research, San Diego Zoo Global, San Diego, California, USA.,Field Projects International, Saint Louis, Missouri, USA
| | - Gideon A Erkenswick
- Field Projects International, Saint Louis, Missouri, USA.,Department of Biology, University of Missouri St. Louis, Saint Louis, Missouri, USA.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Laís A A Moreira
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Canada
| | - Jia Tang
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Canada
| | - Jacob C Dunn
- School of Life Sciences, Anglia Ruskin University, Cambridge, UK.,Biological Anthropology, Department of Archaeology, University of Cambridge, Cambridge, UK.,Department of Cognitive Biology, University of Vienna, Vienna, Austria
| | - Amanda D Melin
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Canada.,Department of Medical Genetics and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
| | - Andrew C Smith
- School of Life Sciences, Anglia Ruskin University, Cambridge, UK
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14
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Elgar MA, Riehl C. Editorial: Mechanisms of Communication and Recognition in Social Evolution. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2020.625831] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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15
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Ramiro CN, Martín J, da Silva Junior PI, Pinto HBA, Magalhães Júnior AJC, Abrahão C, Rodrigues MT. Chemical characterization of the lipids in femoral gland secretions of wild male tegu lizards, Salvator merianae (Squamata, Teiidae) in comparison with captive-bred males. Z NATURFORSCH C 2020; 75:443-449. [PMID: 32598329 DOI: 10.1515/znc-2020-0005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 06/01/2020] [Indexed: 11/15/2022]
Abstract
Although chemical interactions play an essential role in lizard social behavior, the chemical composition of the femoral gland secretions that many lizards use for communication is known for only a few species, mainly European Lacertids. The tegu lizard, Salvator merianae, is the only species of the Teiidae family for which there is available information on lipids in femoral secretions, but only for captive bred males from Argentina. Here, based on mass spectra obtained by GC-MS, we found 69 lipophilic compounds in femoral gland secretions of wild males S. merianae from Brazil, including cholesterol and high amounts of saturated fatty acids (mainly hexadecanoic and octadecanoic). We found contrasting differences between wild and captive-bred males, which lack cholesterol but present high amount of 9,12-octadecadienoic acid. These within-species differences between wild and captive lizards strongly suggest the important influence of different diets on the chemical composition of the femoral gland secretion and suggest caution when interpreting results from captive animals, even in the same species.
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Affiliation(s)
- Carolina N Ramiro
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo, 05508-090, Brazil
| | - José Martín
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, 28006, Spain
| | | | - Hugo B A Pinto
- Centro Nacional de Pesquisa e Conservação de Répteis e Anfíbios, Instituto Chico Mendes de Conservação e Biodiversidade, Goiânia, Goiás, 74605-090, Brazil
| | - Arnaldo José C Magalhães Júnior
- Colegiado Acadêmico de Ciências da Natureza, Universidade Federal do Vale do São Francisco, São Raimundo Nonato, Piauí, 64770-000, Brazil
| | - Carlos Abrahão
- Centro Nacional de Pesquisa e Conservação de Répteis e Anfíbios, Instituto Chico Mendes de Conservação e Biodiversidade, Goiânia, Goiás, 74605-090, Brazil
| | - Miguel T Rodrigues
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo, 05508-090, Brazil
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Raya-García E, Suazo-Ortuño I, Campos-García J, Martín J, Alvarado-Díaz J, Mendoza-Ramírez E. Chemical signal divergence among populations influences behavioral discrimination in the whiptail lizard Aspidoscelis lineattissimus (squamata: teiidae). Behav Ecol Sociobiol 2020. [DOI: 10.1007/s00265-020-02931-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Campos SM, Pruett JA, Soini HA, Zúñiga-Vega JJ, Goldberg JK, Vital-García C, Hews DK, Novotny MV, Martins EP. Volatile fatty acid and aldehyde abundances evolve with behavior and habitat temperature in Sceloporus lizards. Behav Ecol 2020; 31:978-991. [PMID: 32764859 DOI: 10.1093/beheco/araa044] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 03/27/2020] [Accepted: 04/20/2020] [Indexed: 12/28/2022] Open
Abstract
Animal signals evolve by striking a balance between the need to convey information through particular habitats and the limitations of what types of signals can most easily be produced and perceived. Here, we present new results from field measures of undisturbed behavior and biochemical analyses of scent marks from 12 species of Sceloporus lizards to explore whether evolutionary changes in chemical composition are better predicted by measures of species behavior, particularly those associated with visual displays, chemoreception, and locomotion, or by measures of habitat climate (precipitation and temperature). We found that more active lizard species used fewer compounds in their volatile scent marks, perhaps conveying less specific information about individual and species identity. Scent marks from more active lizard species also had higher proportions of saturated fatty acids, and the evolution of these compounds has been tracking the phylogeny closely as we would expect for a metabolic byproduct. In contrast, the proportions of unsaturated fatty acids were better explained by evolutionary shifts in habitat temperature (and not precipitation), with species in warmer climates using almost no volatile unsaturated fatty acids. The proportion of aldehydes was explained by both behavior and environment, decreasing with behavioral activity and increasing with habitat temperature. Our results highlight the evolutionary flexibility of complex chemical signals, with different chemical compounds responding to different elements of the selective landscape over evolutionary time.
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Affiliation(s)
- Stephanie M Campos
- Department of Biology and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN, USA.,Center for Behavioral Neuroscience, Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | - Jake A Pruett
- Department of Biological Sciences, Southeastern Oklahoma State University, Durant, OK, USA
| | - Helena A Soini
- Department of Chemistry and the Institute for Pheromone Research, Indiana University, Bloomington, IN, USA
| | - J Jaime Zúñiga-Vega
- Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Coyoacan, Ciudad de México, Mexico
| | - Jay K Goldberg
- Department of Biology and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN, USA
| | - Cuauhcihuatl Vital-García
- Departamento de Ciencias Veterinarias, Universidad Autónoma de Ciudad Juárez, Anillo envolvente y Estocolmo s/n, Zona PRONAF, Juárez, Chihuahua, CP, Mexico
| | - Diana K Hews
- Department of Biology, Indiana State University, Terre Haute, IN, USA
| | - Milos V Novotny
- Department of Chemistry and the Institute for Pheromone Research, Indiana University, Bloomington, IN, USA
| | - Emília P Martins
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
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18
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Host Plant and Antibiotic Effects on Scent Bouquet Composition of Anastrepha ludens and Anastrepha obliqua Calling Males, Two Polyphagous Tephritid Pests. INSECTS 2020; 11:insects11050309. [PMID: 32423147 PMCID: PMC7290347 DOI: 10.3390/insects11050309] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/02/2020] [Accepted: 05/12/2020] [Indexed: 01/18/2023]
Abstract
In insects, the quality of sex pheromones plays a critical role in mating success and can be determined by the ability of larvae/adults to accrue chemical precursors. We tested the host-quality-effect hypothesis by analyzing the chemical composition of scent bouquets emitted by calling males of two polyphagous tephritid species (Anastrephaludens and A. obliqua) that originated from 13 fruit species representing diverse plant families. In A. ludens, we worked with an ancestral host (Rutaceae), nine exotic ones (Rutaceae, Anacardiaceae, Rosaceae, Solanaceae, Lythraceae), and two species never attacked in nature but that represent candidates for host-range expansion (Solanaceae, Myrtaceae). In A. obliqua, we tested an ancestral, a native, and an exotic host (Anacardiaceae), one occasional (Myrtaceae), and one fruit never attacked in nature (Solanaceae). We identified a core scent bouquet and significant variation in the bouquet’s composition depending on the fruit the larvae developed in. We also tested the possible microbial role on the scent bouquet by treating adults with antibiotics, finding a significant effect on quantity but not composition. We dwell on plasticity to partially explain our results and discuss the influence hosts could have on male competitiveness driven by variations in scent bouquet composition and how this could impact insect sterile technique programs.
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20
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Overlooked Scents: Chemical Profile of Soma, Volatile Emissions and Trails of the Green Tree Ant, Oecophylla smaragdina. Molecules 2020; 25:molecules25092112. [PMID: 32365972 PMCID: PMC7249187 DOI: 10.3390/molecules25092112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 04/23/2020] [Accepted: 04/28/2020] [Indexed: 12/30/2022] Open
Abstract
The green tree ant, Oecophylla smaragdina, is one of only two recognized species of weaver ants. While the identity and functions of chemicals produced and emitted by its congener O. longinoda have been studied quite extensively and serve as a valuable model in chemical ecology research, little comparable information is available about O. smaragdina. Although some analyses of chemicals produced and emitted by O. smaragdina have been reported, the literature is fragmentary and incomplete for this species. To address this knowledge gap, and to enable comparisons in the chemical ecology of the two weaver ant species, we here describe diverse chemicals from the cuticle, Dufour's glands, poison glands, head, headspace volatiles, and trails of O. smaragdina.
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Achorn AM, Rosenthal GG. It’s Not about Him: Mismeasuring ‘Good Genes’ in Sexual Selection. Trends Ecol Evol 2020; 35:206-219. [DOI: 10.1016/j.tree.2019.11.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 11/24/2019] [Accepted: 11/26/2019] [Indexed: 01/18/2023]
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22
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Darragh K, Byers KJRP, Merrill RM, McMillan WO, Schulz S, Jiggins CD. Male pheromone composition depends on larval but not adult diet in Heliconius melpomene. ECOLOGICAL ENTOMOLOGY 2019; 44:397-405. [PMID: 31217661 PMCID: PMC6563479 DOI: 10.1111/een.12716] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 11/29/2018] [Accepted: 11/30/2018] [Indexed: 06/09/2023]
Abstract
1. Condition-dependent traits can act as honest signals of mate quality, with fitter individuals being able to display preferred phenotypes. Nutrition is known to be an important determinant of individual condition, with diet known to affect many secondary sexual traits. 2. In Heliconius butterflies, male chemical signalling plays an important role in female mate choice. Potential male sex pheromone components have been identified previously, although it is unclear what information they convey to the female. 3. In the present study, the effect of diet on androconial and genital compound production is tested in male Heliconius melpomene rosina. To manipulate larval diet, larvae are reared on three different Passiflora host plants: Passiflora menispermifolia, the preferred host plant, Passiflora vitifolia and Passiflora platyloba. To manipulate adult diet, adult butterflies are reared with and without access to pollen, a key component of their diet. 4. No evidence is found to suggest that adult pollen consumption affects compound production in the first 10 days after eclosion. There is also a strong overlap in the chemical profiles of individuals reared on different larval host plants. The most abundant compounds produced by the butterflies do not differ between host plant groups. However, some compounds found in small amounts differ both qualitatively and quantitatively. Some of these compounds are predicted to be of plant origin and the others synthesised by the butterfly. Further electrophysiological and behavioural experiments will be needed to determine the biological significance of these differences.
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Affiliation(s)
- Kathy Darragh
- Department of ZoologyUniversity of CambridgeCambridgeU.K.
- Smithsonian Tropical Research InstitutePanama
| | - Kelsey J. R. P. Byers
- Department of ZoologyUniversity of CambridgeCambridgeU.K.
- Smithsonian Tropical Research InstitutePanama
| | - Richard M. Merrill
- Smithsonian Tropical Research InstitutePanama
- Division of Evolutionary BiologyLudwig‐Maximilians‐UniversitätMunichGermany
| | | | - Stefan Schulz
- Department of Life Sciences, Institute of Organic Chemistry, Institute of Organic ChemistryTechnische Universität BraunschweigBraunschweigGermany
| | - Chris D. Jiggins
- Department of ZoologyUniversity of CambridgeCambridgeU.K.
- Smithsonian Tropical Research InstitutePanama
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23
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Chen ZW, Zhao YF, He SC, Liu KK, Liu JH, Xiao YH. Particular Levels of Odors Released by Virgin Females Attract Conspecific Males of the Funnel-Web Spider Allagelena difficilis. J Chem Ecol 2018; 44:905-914. [PMID: 30097768 DOI: 10.1007/s10886-018-0998-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/02/2018] [Accepted: 07/16/2018] [Indexed: 11/27/2022]
Abstract
Female-released chemical signals are crucial clues for mate-searching males to locate and gain sexual receptivity of conspecific females. Abundant behavioral evidence indicates that female spiders release sex pheromones to guide mate-searching behavior of conspecific mature males. However, the chemical nature of spider pheromones is poorly understood. Females of the funnel-web spider, Allagelena difficilis, employ sit-and-wait tactics for mating. Field observations indicate that males leave their retreats to search for potential mates during the breeding season. Therefore, we investigated whether virgin females release a sex attractant to conspecific males and then explored the chemical nature of the female pheromone. Four fatty acids extracted from the female bodies (palmitic acid, linoleic acid, cis-vaccenic acid and stearic acid) constitute a multiple-component sex attractant to conspecific males in A. difficilis. Unexpectedly, mated females also produce the same fatty acids, but at trace levels. Two-choice experiments showed that males were significantly attracted by the blend of the four fatty acids in appropriate concentrations while avoiding the blend consisting of the same acids at very low concentrations, suggesting that mate-searching males are able to discriminate virgin females from mated females by the quantities of female-specific fatty acids in the funnel-web spider A. difficilis.
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Affiliation(s)
- Zhi-Wu Chen
- College of Life Sciences, Jinggangshan University, Ji'an, 343009, Jiangxi, China
- School of Agricultural Sciences, Jiangxi Agricultural University, Nanchang, 330045, Jiangxi, China
| | - Yi-Fan Zhao
- College of Life Sciences, Jinggangshan University, Ji'an, 343009, Jiangxi, China
| | - Shi-Cong He
- College of Life Sciences, Jinggangshan University, Ji'an, 343009, Jiangxi, China
| | - Ke-Ke Liu
- College of Life Sciences, Jinggangshan University, Ji'an, 343009, Jiangxi, China
| | - Ji-He Liu
- College of Life Sciences, Jinggangshan University, Ji'an, 343009, Jiangxi, China
- College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, China
| | - Yong-Hong Xiao
- College of Life Sciences, Jinggangshan University, Ji'an, 343009, Jiangxi, China.
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24
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Noonan MJ, Tinnesand HV, Buesching CD. Normalizing Gas-Chromatography-Mass Spectrometry Data: Method Choice can Alter Biological Inference. Bioessays 2018; 40:e1700210. [PMID: 29709068 DOI: 10.1002/bies.201700210] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 03/05/2018] [Indexed: 12/26/2022]
Abstract
We demonstrate how different normalization techniques in GC-MS analysis impart unique properties to the data, influencing any biological inference. Using simulations, and empirical data, we compare the most commonly used techniques (Total Sum Normalization 'TSN'; Median Normalization 'MN'; Probabilistic Quotient Normalization 'PQN'; Internal Standard Normalization 'ISN'; External Standard Normalization 'ESN'; and a compositional data approach 'CODA'). When differences between biological classes are pronounced, ESN and ISN provides good results, but are less reliable for more subtly differentiated groups. MN, TSN, and CODA approaches produced variable results dependent on the structure of the data, and are prone to false positive biomarker identification. In contrast, PQN exhibits the lowest false positive rate, though with occasionally poor model performance. Because ESN requires extensive pre-planning, and offers only mixed reliability, and ISN, TSN, MN, and CODA approaches are prone to introducing artefactual differences, we recommend the use of PQN in GC-MS research.
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Affiliation(s)
- Michael J Noonan
- Smithsonian Conservation Biology Institute, National Zoological Park, 1500 Remount Rd., Front Royal, VA 22630, USA
| | - Helga V Tinnesand
- Faculty of Technology, Natural Sciences, and Maritime Sciences, Department of Natural Sciences and Environmental Health, University College of Southeast Norway, 3800 Bø i Telemark, Norway
| | - Christina D Buesching
- Wildlife Conservation Research Unit, Zoology Department, The Recanati-Kaplan Centre, University of Oxford, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK
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25
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Merli D, Mannucci B, Bassetti F, Corana F, Falchetto M, Malacrida AR, Gasperi G, Scolari F. Larval Diet Affects Male Pheromone Blend in a Laboratory Strain of the Medfly, Ceratitis capitata (Diptera: Tephritidae). J Chem Ecol 2018; 44:339-353. [PMID: 29504084 DOI: 10.1007/s10886-018-0939-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/02/2018] [Accepted: 02/18/2018] [Indexed: 11/29/2022]
Abstract
The Mediterranean fruit fly (medfly) Ceratitis capitata is a polyphagous pest of fruits and crops with a worldwide distribution. Its ability to use different larval hosts may have multiple effects, including impacts on adult reproductive biology. The male sex pheromone, which plays a key role in attracting both other males to lekking arenas and females for mating, is a mixture of chemical compounds including esters, acids, alkanes and terpenes known to differ between laboratory strains and wild-type populations. The relationship between larval diet and adult pheromone composition remains unexplored. Here, we investigated the effect of larval diet, including laboratory media and fresh fruits, on the composition of the male pheromone mixture. Using Headspace Solid Phase Microextraction we collected the pheromone emitted by males reared as larvae on different substrates and found both qualitative and quantitative differences. A number of alkanes appeared to be typical of the pheromone of males reared on wheat bran-based larval medium, and these may be cuticular hydrocarbons involved in chemical communication. We also detected differences in pheromone composition related to adult male age, suggesting that variations in hormonal levels and/or adult diet could also play a role in determining the chemical profile emitted. Our findings highlight the plasticity of dietary responses of C. capitata, which may be important in determining the interactions of this pest with the environment and with conspecifics. These results also have applied relevance to increase the mating competitiveness of mass-reared C. capitata used in Sterile Insect Technique programs.
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Affiliation(s)
- Daniele Merli
- Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy
| | - Barbara Mannucci
- Centro Grandi Strumenti, University of Pavia, Via Bassi 21, 27100, Pavia, Italy
| | - Federico Bassetti
- Department of Mathematics, University of Pavia, Via Ferrata 5, 27100, Pavia, Italy
| | - Federica Corana
- Centro Grandi Strumenti, University of Pavia, Via Bassi 21, 27100, Pavia, Italy
| | - Marco Falchetto
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - Anna R Malacrida
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - Giuliano Gasperi
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - Francesca Scolari
- Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100, Pavia, Italy.
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26
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Otte T, Hilker M, Geiselhardt S. Phenotypic Plasticity of Cuticular Hydrocarbon Profiles in Insects. J Chem Ecol 2018; 44:235-247. [PMID: 29468480 DOI: 10.1007/s10886-018-0934-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 02/05/2018] [Accepted: 02/08/2018] [Indexed: 12/28/2022]
Abstract
The insect integument is covered by cuticular hydrocarbons (CHCs) which provide protection against environmental stresses, but are also used for communication. Here we review current knowledge on environmental and insect-internal factors which shape phenotypic plasticity of solitary living insects, especially herbivorous ones. We address the dynamics of changes which may occur within minutes, but may also last weeks, depending on the species and conditions. Two different modes of changes are suggested, i.e. stepwise and gradual. A switch between two distinct environments (e.g. host plant switch by phytophagous insects) results in stepwise formation of two distinct adaptive phenotypes, while a gradual environmental change (e.g. temperature gradients) induces a gradual change of numerous adaptive CHC phenotypes. We further discuss the ecological and evolutionary consequences of phenotypic plasticity of insect CHC profiles by addressing the question at which conditions is CHC phenotypic plasticity beneficial. The high plasticity of CHC profiles might be a trade-off for insects using CHCs for communication. We discuss how insects cope with the challenge to produce and "understand" a highly plastic, environmentally dependent CHC pattern that conveys reliable and comprehensible information. Finally, we outline how phenotypic plasticity of CHC profiles may promote speciation in insects that rely on CHCs for mate recognition.
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Affiliation(s)
- Tobias Otte
- Institute of Biology, Freie Universität Berlin, Haderslebener Str. 9, 12163, Berlin, Germany
| | - Monika Hilker
- Institute of Biology, Freie Universität Berlin, Haderslebener Str. 9, 12163, Berlin, Germany
| | - Sven Geiselhardt
- Institute of Biology, Freie Universität Berlin, Haderslebener Str. 9, 12163, Berlin, Germany.
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27
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García-Roa R, Megía-Palma R, Ortega J, Jara M, López P, Martín J. Interpopulational and seasonal variation in the chemical signals of the lizard Gallotia galloti. PeerJ 2017; 5:e3992. [PMID: 29230352 PMCID: PMC5721911 DOI: 10.7717/peerj.3992] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 10/15/2017] [Indexed: 11/20/2022] Open
Abstract
Communicative traits are strikingly diverse and may vary among populations of the same species. Within a population, these traits may also display seasonal variation. Chemical signals play a key role in the communication of many taxa. However, we still know far too little about chemical communication in some vertebrate groups. In lizards, only a few studies have examined interpopulational variation in the composition of chemical cues and signals and only one study has explored the seasonal effects. Here we sampled three subspecies of the Tenerife lizards (Gallotia galloti) and analyze the lipophilic fraction of their femoral gland secretions to characterize the potential interpopulational variation in the chemical signals. In addition, we assessed whether composition of these secretions differed between the reproductive and the non-reproductive season. We analyzed variations in both the overall chemical profile and the abundance of the two main compounds (cholesterol and vitamin E). Our results show interpopulational and seasonal differences in G. gallotia chemical profiles. These findings are in accordance with the high interpopulational variability of compounds observed in lizard chemical signals and show that their composition is not only shaped by selective factors linked to reproductive season.
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Affiliation(s)
- Roberto García-Roa
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - Rodrigo Megía-Palma
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - Jesús Ortega
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - Manuel Jara
- Laboratory of Evolutionary Ecology of Adaptations, School of Life Sciences, University of Lincoln, Lincoln, United Kingdom
| | - Pilar López
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
| | - José Martín
- Department of Evolutionary Ecology, National Museum of Natural Sciences (MNCN-CSIC), Madrid, Spain
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28
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Henneken J, Jones TM. Pheromones-based sexual selection in a rapidly changing world. CURRENT OPINION IN INSECT SCIENCE 2017; 24:84-88. [PMID: 29208228 DOI: 10.1016/j.cois.2017.09.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/08/2017] [Accepted: 09/18/2017] [Indexed: 06/07/2023]
Abstract
Insects utilise chemical cues for a range of different purposes and the complexity and degree of specificity of these signals is arguably unparalleled in the animal kingdom. Chemical signals are particularly important for insect reproduction and the selective pressures driving their evolution and maintenance have been the subject of previous reviews. However, the world in which chemical cues evolved and are maintained is changing at an unprecedented rate. How (or indeed whether) chemical signals used in sexual selection will respond is largely unknown. Here, we explore how recent increases in urbanisation and associated anthropogenic impacts may affect how chemical signals are produced and perceived. We focus on four anthropomorphic influences which have the potential to interact with pheromone-mediated sexual selection processes; climatic temperature shifts, exposure to chemical pollutants, the presence of artificial light at night and nutrient availability. Our aim is to provide a broad overview of key areas where the rapidly changing environment of the future might specifically affect pheromones utilised in sexual selection.
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Affiliation(s)
- Jessica Henneken
- The School of BioSciences, The University of Melbourne, Victoria, Australia
| | - Therésa M Jones
- The School of BioSciences, The University of Melbourne, Victoria, Australia.
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29
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Stökl J, Steiger S. Evolutionary origin of insect pheromones. CURRENT OPINION IN INSECT SCIENCE 2017; 24:36-42. [PMID: 29208221 DOI: 10.1016/j.cois.2017.09.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 08/11/2017] [Accepted: 09/06/2017] [Indexed: 06/07/2023]
Abstract
Communication via chemical signals, that is, pheromones, is of pivotal importance for most insects. According to current evolutionary theory, insect pheromones originated either from extant precursor compounds being selected for information transfer or by the pheromone components exploiting a pre-existing sensory bias in the receiver. Here, we review the available experimental evidence for both hypotheses. Existing data indicate that most insect pheromones evolved from precursor compounds that were emitted as metabolic by-products or that previously had other non-communicative functions. Many studies have investigated cuticular hydrocarbons that have evolved a communicative function, although examples of pheromones exist that have arisen from defensive secretions, hormones or dietary compounds. We summarize and discuss the selective pressures shaping the pheromone during signal evolution.
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Affiliation(s)
- Johannes Stökl
- Institute of Insect Biotechnology, Justus-Liebig-University Gießen, Heinrich-Buff-Ring 26-32, 35392 Gießen, Germany.
| | - Sandra Steiger
- Institute of Insect Biotechnology, Justus-Liebig-University Gießen, Heinrich-Buff-Ring 26-32, 35392 Gießen, Germany
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30
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Henneken J, Goodger JQD, Jones TM, Elgar MA. Variation in the web-based chemical cues of Argiope keyserlingi. JOURNAL OF INSECT PHYSIOLOGY 2017; 101:15-21. [PMID: 28606855 DOI: 10.1016/j.jinsphys.2017.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 06/02/2017] [Accepted: 06/07/2017] [Indexed: 06/07/2023]
Abstract
Pheromones are chemical compounds used to transmit information between individuals of the same species. Pheromone composition is influenced by both genetic and environmental factors. Numerous studies, predominately of insects, have demonstrated a role for diet in pheromone expression. The chemical composition of spider web-silk varies with diet and in many species these chemicals are crucial to mate choice processes. Here, we investigated individual variation in the chemical compounds found on the surface of web-silk of female Argiope keyserlingi, and further explored the degree to which they are influenced by diet, investment in egg sac production and site of collection. We observed variation in the web-based chemical cues both between and within individuals. Additionally, we found that some of this variation could be explained by diet and gravid status but not by collection site. We discuss our findings in relation to mate choice processes and the costs and benefits of the observed variation in these web-based chemicals.
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Affiliation(s)
- Jessica Henneken
- School of Biosciences, The University of Melbourne, Victoria, Australia.
| | - Jason Q D Goodger
- School of Biosciences, The University of Melbourne, Victoria, Australia
| | - Therèsa M Jones
- School of Biosciences, The University of Melbourne, Victoria, Australia
| | - Mark A Elgar
- School of Biosciences, The University of Melbourne, Victoria, Australia
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García-Roa R, Sáiz J, Gómara B, López P, Martín J. Dietary constraints can preclude the expression of an honest chemical sexual signal. Sci Rep 2017; 7:6073. [PMID: 28729717 PMCID: PMC5519758 DOI: 10.1038/s41598-017-06323-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 06/12/2017] [Indexed: 11/19/2022] Open
Abstract
Identifying the factors that underlie signal divergences remains challenging in studies of animal communication. Regarding the chemical signalling, different compounds can be found in some species but be absent in others. We hypothesized that if the costs that are associated with the expression of some compounds are too high, their presence in the signal may be restricted. However, these compounds may be expressed and be functional when those costs are relaxed. Vitamin E (α-tocopherol), a dietary compound with metabolic relevancy, acts as an honest chemical sexual signal in many lizards but no in others such as the Carpetan Rock lizard (Iberolacerta cyreni). We investigated whether dietary supplementation favours the expression of this vitamin in scents of I. cyreni. We show that dietary constraints can preclude the expression of vitamin E in chemical secretions of wild males because was expressed when it was experimentally provided in the diet. Vitamin E supplementation also heightened the immune response of males and increased the interest of their scent for females, highlighting the vitamin E as a chemical sexual signal in this species. We suggest that diet could decisively act as a driver of intra- and interspecific divergences in the chemical signalling of lizards.
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Affiliation(s)
- Roberto García-Roa
- Department of Evolutionary Ecology, National Museum of Natural Sciences, Spanish Research Council (MNCN- CSIC), José Gutiérrez Abascal, 2, 28006, Madrid, Spain.
| | - Jorge Sáiz
- Department of Instrumental Analysis and Environmental Chemistry, Spanish Research Council (IQOG- CSIC), Juan de la Cierva, 3, 28006, Madrid, Spain
| | - Belén Gómara
- Department of Instrumental Analysis and Environmental Chemistry, Spanish Research Council (IQOG- CSIC), Juan de la Cierva, 3, 28006, Madrid, Spain
| | - Pilar López
- Department of Evolutionary Ecology, National Museum of Natural Sciences, Spanish Research Council (MNCN- CSIC), José Gutiérrez Abascal, 2, 28006, Madrid, Spain
| | - José Martín
- Department of Evolutionary Ecology, National Museum of Natural Sciences, Spanish Research Council (MNCN- CSIC), José Gutiérrez Abascal, 2, 28006, Madrid, Spain
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