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Romei F, Schilman PE. Diatomaceous earth as insecticide: physiological and morphological evidence of its underlying mechanism. PEST MANAGEMENT SCIENCE 2024; 80:3301-3307. [PMID: 38372489 DOI: 10.1002/ps.8033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 02/14/2024] [Accepted: 02/19/2024] [Indexed: 02/20/2024]
Abstract
BACKGROUND Wheat grain containers or silos can be perfect habitats for insects, which generate large economic losses to grain production. Natural alternatives to synthetic insecticides have grown in popularity because of health, economic and ecological issues. Diatomaceous earth is a natural compound that has an insecticide effect by enhancing an insect's dehydration with no toxicity on mammals including humans. The aim of this study is to confirm the effect of diatomaceous earth as an insecticide for the wheat grain pest, the red flour beetle Tribolium castaneum (Coleoptera: Tenebrionidae) and demonstrate its underlying mechanisms as an insecticide by open-flow respirometry and scanning electron microscopy. RESULTS Survival bioassays of T. castaneum revealed a dose-dependent insecticide effect of diatomaceous earth. Gravimetric measurements showed that 2 days exposure to diatomaceous earth produces a significant increase of mass loss. Open-flow respirometry measurements showed an increase of total water emission rate on insects due to an increase of both, respiratory and cuticular water loss. Our study revealed that diatomaceous earth produces an increase of insect's cuticle permeability, which is responsible for elevated cuticular water loss. Scanning electron microscopy images provided visual evidence of the lipid absorbent properties of diatomaceous earth particles, and showed a tendency for higher, although not significant, damaged area of the cuticle's surface from diatomaceous earth treated insects compared to control ones. CONCLUSION With state-of-the art techniques like open-flow respirometry and scanning electron microscopy, we demonstrated the underlying mechanism of diatomaceous earth as an insecticide and provided new cues for understanding the properties of the cuticle and its ecological importance. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Francisco Romei
- Departamento de Biodiversidad y Biología Experimental (DBBE), Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), CONICET-UBA, Buenos Aires, Argentina
| | - Pablo E Schilman
- Departamento de Biodiversidad y Biología Experimental (DBBE), Facultad de Ciencias Exactas y Naturales (FCEyN), Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), CONICET-UBA, Buenos Aires, Argentina
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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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Carlassara M, Khorramnejad A, Oker H, Bahrami R, Lozada-Chávez AN, Mancini MV, Quaranta S, Body MJA, Lahondère C, Bonizzoni M. Population-specific responses to developmental temperature in the arboviral vector Aedes albopictus: Implications for climate change. GLOBAL CHANGE BIOLOGY 2024; 30:e17226. [PMID: 38454541 DOI: 10.1111/gcb.17226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 02/20/2024] [Accepted: 02/21/2024] [Indexed: 03/09/2024]
Abstract
The increase of environmental temperature due to current global warming is not only favouring the expansion of the distribution range of many insect species, but it is also changing their phenology. Insect phenology is tightly linked to developmental timing, which is regulated by environmental temperatures. However, the degree to which the effects of developmental temperatures extend across developmental stages and their inter-stage relationships have not been thoroughly quantified in mosquitoes. Here, we used the mosquito Aedes albopictus, which is an aggressive invasive species and an arboviral vector, to study how developmental temperature influences fitness across developmental stages, thermal traits, energy reserves, transcriptome and Wolbachia prevalence in laboratory-reared populations originally collected from either temperate or tropical regions. We show that hatchability, larval and pupal viability and developmental speed are strongly influenced by temperature, and these effects extend to wing length, body mass, longevity and content of water, protein and lipids in adults in a population-specific manner. On the contrary, neither adult thermal preference nor heat resistance significantly change with temperature. Wolbachia density was generally lower in adult mosquitoes reared at 18°C than at other tested temperatures, and transcriptome analysis showed enrichment for functions linked to stress responses (i.e. cuticle proteins and chitin, cytochrome p450 and heat shock proteins) in mosquitoes reared at both 18 and 32°C. Our data showed an overall reduced vector fitness performance when mosquitoes were reared at 32°C, and the absence of isomorphy in the relationship between developmental stages and temperature in the laboratory population deriving from larvae collected in northern Italy. Altogether, these results have important implications for reliable model projections of the invasion potentials of Ae. albopictus and its epidemiological impact.
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Affiliation(s)
- Martina Carlassara
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Ayda Khorramnejad
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Helen Oker
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
| | - Romina Bahrami
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | | | | | - Stefano Quaranta
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Mélanie J A Body
- Department of Horticulture, Michigan State University, East Lansing, Michigan, USA
| | - Chloé Lahondère
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
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Janzen A, Pothula R, Sychla A, Feltman NR, Smanski MJ. Predicting thresholds for population replacement gene drives. BMC Biol 2024; 22:40. [PMID: 38369493 PMCID: PMC10875781 DOI: 10.1186/s12915-024-01823-2] [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: 06/30/2023] [Accepted: 01/10/2024] [Indexed: 02/20/2024] Open
Abstract
BACKGROUND Threshold-dependent gene drives (TDGDs) could be used to spread desirable traits through a population, and are likely to be less invasive and easier to control than threshold-independent gene drives. Engineered Genetic Incompatibility (EGI) is an extreme underdominance system previously demonstrated in Drosophila melanogaster that can function as a TDGD when EGI agents of both sexes are released into a wild-type population. RESULTS Here we use a single generation fitness assay to compare the fecundity, mating preferences, and temperature-dependent relative fitness to wild-type of two distinct genotypes of EGI agents. We find significant differences in the behavior/performance of these EGI agents that would not be predicted a priori based on their genetic design. We report a surprising temperature-dependent change in the predicted threshold for population replacement in an EGI agent that drives ectopic expression of the developmental morphogen pyramus. CONCLUSIONS The single-generation fitness assay presented here could reduce the amount of time required to estimate the threshold for TDGD strategies for which hybrid genotypes are inviable. Additionally, this work underscores the importance of empirical characterization of multiple engineered lines, as behavioral differences can arise in unique genotypes for unknown reasons.
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Affiliation(s)
- Anna Janzen
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, 55455, MN, USA
- Biotechnology Institute, University of Minnesota, Saint Paul, 55108, MN, USA
| | - Ratnasri Pothula
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, 55455, MN, USA
- Biotechnology Institute, University of Minnesota, Saint Paul, 55108, MN, USA
| | - Adam Sychla
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, 55455, MN, USA
- Biotechnology Institute, University of Minnesota, Saint Paul, 55108, MN, USA
| | - Nathan R Feltman
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, 55455, MN, USA
- Biotechnology Institute, University of Minnesota, Saint Paul, 55108, MN, USA
| | - Michael J Smanski
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, 55455, MN, USA.
- Biotechnology Institute, University of Minnesota, Saint Paul, 55108, MN, USA.
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Mitchell C, Wylde Z, Del Castillo E, Rapkin J, House CM, Hunt J. Beauty or function? The opposing effects of natural and sexual selection on cuticular hydrocarbons in male black field crickets. J Evol Biol 2023; 36:1266-1281. [PMID: 37534753 DOI: 10.1111/jeb.14198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 04/21/2023] [Accepted: 05/10/2023] [Indexed: 08/04/2023]
Abstract
Although many theoretical models of male sexual trait evolution assume that sexual selection is countered by natural selection, direct empirical tests of this assumption are relatively uncommon. Cuticular hydrocarbons (CHCs) are known to play an important role not only in restricting evaporative water loss but also in sexual signalling in most terrestrial arthropods. Insects adjusting their CHC layer for optimal desiccation resistance is often thought to come at the expense of successful sexual attraction, suggesting that natural and sexual selection are in opposition for this trait. In this study, we sampled the CHCs of male black field crickets (Teleogryllus commodus) using solid-phase microextraction and then either measured their evaporative water loss or mating success. We then used multivariate selection analysis to quantify the strength and form of natural and sexual selection targeting male CHCs. Both natural and sexual selection imposed significant linear and stabilizing selection on male CHCs, although for very different combinations. Natural selection largely favoured an increase in the total abundance of CHCs, especially those with a longer chain length. In contrast, mating success peaked at a lower total abundance of CHCs and declined as CHC abundance increased. However, mating success did improve with an increase in a number of specific CHC components that also increased evaporative water loss. Importantly, this resulted in the combination of male CHCs favoured by natural selection and sexual selection being strongly opposing. Our findings suggest that the balance between natural and sexual selection is likely to play an important role in the evolution of male CHCs in T. commodus and may help explain why CHCs are so divergent across populations and species.
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Affiliation(s)
- Christopher Mitchell
- Centre for Ecology & Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn, UK
| | - Zachariah Wylde
- School of Science, Western Sydney University, Hawkesbury Campus, Penrith, New South Wales, Australia
| | - Enrique Del Castillo
- Department of Industrial & Manufacturing Engineering and Department of Statistics, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - James Rapkin
- Centre for Ecology & Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn, UK
| | - Clarissa M House
- School of Science, Western Sydney University, Hawkesbury Campus, Penrith, New South Wales, Australia
| | - John Hunt
- Centre for Ecology & Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn, UK
- School of Science, Western Sydney University, Hawkesbury Campus, Penrith, New South Wales, Australia
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Pokorny T, Ruther J. Cuticular Hydrocarbon Polymorphism in a Parasitoid Wasp. J Chem Ecol 2023; 49:36-45. [PMID: 36705801 PMCID: PMC9941234 DOI: 10.1007/s10886-022-01401-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 12/19/2022] [Accepted: 12/21/2022] [Indexed: 01/28/2023]
Abstract
Cuticular hydrocarbons (CHCs) are major constituents of the cuticular lipid layer of insects. They serve not only as a barrier to desiccation, but often additionally mediate communication at close range. The compositions of the CHC profiles, i.e., the specific compounds and their relative amounts, usually differ between species. Additional intraspecific variability can be found between different populations, between colonies and castes of social insects, and between the sexes. Thus, such groups can often be distinguished based on distinctive compounds and/or specific compound ratios. The CHC profile may further be influenced by biotic and abiotic factors, which therefore can impact, e.g., nestmate recognition or mate choice. However, consistent intrasexual variation seems to be rare. Here, we investigated a case of intrasexual CHC variability within a single population of a parasitoid wasp. While wasps of both sexes produced the same set of compounds, the relative amounts of specific compound classes revealed the presence of intrasexual chemical phenotypes. This is, to our knowledge, the first report of three distinct female CHC profile patterns within a population of a solitary insect that uses CHCs for mate recognition. Additionally, male CHC profiles, while overall very similar, could be separated into two chemotypes by multivariate analysis. The study of species exhibiting such intraspecific and intrasexual CHC variation will advance our understanding of the effects of CHC variability on both, desiccation resistance and intraspecific communication.
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Affiliation(s)
- Tamara Pokorny
- Institute of Zoology, University of Regensburg, Regensburg, Germany.
| | - Joachim Ruther
- grid.7727.50000 0001 2190 5763Institute of Zoology, University of Regensburg, Regensburg, Germany
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Wang Z, Receveur JP, Pu J, Cong H, Richards C, Liang M, Chung H. Desiccation resistance differences in Drosophila species can be largely explained by variations in cuticular hydrocarbons. eLife 2022; 11:e80859. [PMID: 36473178 PMCID: PMC9757832 DOI: 10.7554/elife.80859] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
Maintaining water balance is a universal challenge for organisms living in terrestrial environments, especially for insects, which have essential roles in our ecosystem. Although the high surface area to volume ratio in insects makes them vulnerable to water loss, insects have evolved different levels of desiccation resistance to adapt to diverse environments. To withstand desiccation, insects use a lipid layer called cuticular hydrocarbons (CHCs) to reduce water evaporation from the body surface. It has long been hypothesized that the water-proofing capability of this CHC layer, which can confer different levels of desiccation resistance, depends on its chemical composition. However, it is unknown which CHC components are important contributors to desiccation resistance and how these components can determine differences in desiccation resistance. In this study, we used machine-learning algorithms, correlation analyses, and synthetic CHCs to investigate how different CHC components affect desiccation resistance in 50 Drosophila and related species. We showed that desiccation resistance differences across these species can be largely explained by variation in CHC composition. In particular, length variation in a subset of CHCs, the methyl-branched CHCs (mbCHCs), is a key determinant of desiccation resistance. There is also a significant correlation between the evolution of longer mbCHCs and higher desiccation resistance in these species. Given that CHCs are almost ubiquitous in insects, we suggest that evolutionary changes in insect CHC components can be a general mechanism for the evolution of desiccation resistance and adaptation to diverse and changing environments.
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Affiliation(s)
- Zinan Wang
- Department of Entomology, Michigan State UniversityEast LansingUnited States
- Ecology, Evolution, and Behavior Program, Michigan State UniversityEast LansingUnited States
| | - Joseph P Receveur
- Department of Entomology, Michigan State UniversityEast LansingUnited States
- Ecology, Evolution, and Behavior Program, Michigan State UniversityEast LansingUnited States
- Institute for Genome Sciences, University of MarylandBaltimoreUnited States
| | - Jian Pu
- Department of Entomology, Michigan State UniversityEast LansingUnited States
- College of Agriculture, Sichuan Agricultural UniversitySichuanChina
| | - Haosu Cong
- Department of Entomology, Michigan State UniversityEast LansingUnited States
| | - Cole Richards
- Department of Entomology, Michigan State UniversityEast LansingUnited States
| | - Muxuan Liang
- Department of Biostatistics, University of FloridaGainesvilleUnited States
| | - Henry Chung
- Department of Entomology, Michigan State UniversityEast LansingUnited States
- Ecology, Evolution, and Behavior Program, Michigan State UniversityEast LansingUnited States
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O'Donnell MJ. A perspective on insect water balance. J Exp Biol 2022; 225:274935. [PMID: 35363855 DOI: 10.1242/jeb.242358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Insects have a large ratio of surface area to volume because of their small size; thus, they face the potential for desiccation in the terrestrial environment. Nonetheless, they constitute over half of identified species and their success on land can be attributed, in part, to adaptations that limit water loss and allow for effective gains of water from food, fluids or atmospheric water vapour. Reduction of water loss from the gut involves sophisticated mechanisms of ion recycling and water recovery by epithelia of the Malpighian tubules and hindgut. Water loss across the body surface is greatly reduced by the evolution of very thin but highly impermeable lipid-rich layers in the epicuticle. Respiratory water loss can be reduced through effective spiracular control mechanisms and by mechanisms for convective rather than diffusive gas exchange. In addition to extracting water from food sources, some insects are capable of absorption of atmospheric water vapour through processes that have evolved independently in multiple groups.
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Affiliation(s)
- Michael J O'Donnell
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, CanadaL8S 4K1
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Kanyile SN, Engl T, Kaltenpoth M. Nutritional symbionts enhance structural defence against predation and fungal infection in a grain pest beetle. J Exp Biol 2022; 225:jeb243593. [PMID: 34854911 PMCID: PMC8778805 DOI: 10.1242/jeb.243593] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/26/2021] [Indexed: 01/18/2023]
Abstract
Many insects benefit from bacterial symbionts that provide essential nutrients and thereby extend the hosts' adaptive potential and their ability to cope with challenging environments. However, the implications of nutritional symbioses for the hosts' defence against natural enemies remain largely unstudied. Here, we investigated whether the cuticle-enhancing nutritional symbiosis of the saw-toothed grain beetle Oryzaephilus surinamensis confers protection against predation and fungal infection. We exposed age-defined symbiotic and symbiont-depleted (aposymbiotic) beetles to two antagonists that must actively penetrate the cuticle for a successful attack: wolf spiders (Lycosidae) and the fungal entomopathogen Beauveria bassiana. While young beetles suffered from high predation and fungal infection rates regardless of symbiont presence, symbiotic beetles were able to escape this period of vulnerability and reach high survival probabilities significantly faster than aposymbiotic beetles. To understand the mechanistic basis of these differences, we conducted a time-series analysis of cuticle development in symbiotic and aposymbiotic beetles by measuring cuticular melanisation and thickness. The results reveal that the symbionts accelerate their host's cuticle formation and thereby enable it to quickly reach a cuticle quality threshold that confers structural protection against predation and fungal infection. Considering the widespread occurrence of cuticle enhancement via symbiont-mediated tyrosine supplementation in beetles and other insects, our findings demonstrate how nutritional symbioses can have important ecological implications reaching beyond the immediate nutrient-provisioning benefits.
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Affiliation(s)
- Sthandiwe Nomthandazo Kanyile
- Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University, 55128 Mainz, Germany
- Department of Insect Symbiosis, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Tobias Engl
- Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University, 55128 Mainz, Germany
- Department of Insect Symbiosis, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Martin Kaltenpoth
- Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg-University, 55128 Mainz, Germany
- Department of Insect Symbiosis, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
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Lorenzi MC. Chemically Insignificant Social Parasites Exhibit More Anti-Dehydration Behaviors than Their Hosts. INSECTS 2021; 12:insects12111006. [PMID: 34821806 PMCID: PMC8624806 DOI: 10.3390/insects12111006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/25/2021] [Accepted: 10/29/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary Social parasites use a variety of deceptive mechanisms to avoid detection by their social-insect hosts and get tolerance in their colonies. One of these mechanisms is chemical insignificance, where social parasites have reduced amounts of recognition cues—hydrocarbons—on their cuticle, thus evading host chemical detection. This exposes social parasites to dehydration stress, as cuticular hydrocarbons also limit body water loss. By analyzing behavioral data from field observations, here we show that a Polistes wasp social parasite exhibits water-saving behaviors; parasites were less active than their cohabiting host foundresses, spent more time at the nest, and rested in the shadow, contradicting the rule that dominant individuals occupy prominent positions at the nest. Abstract Social parasites have evolved adaptations to overcome host resistance as they infiltrate host colonies and establish there. Among the chemical adaptations, a few species are chemically “insignificant”; they are poor in recognition cues (cuticular hydrocarbons) and evade host detection. As cuticular hydrocarbons also serve a waterproofing function, chemical insignificance is beneficial as it protects parasites from being detected but is potentially harmful because it exposes parasites to desiccation stress. Here I tested whether the social parasites Polistes atrimandibularis employ behavioral water-saving strategies when they live at Polistes biglumis colonies. Observations in the field showed that parasites were less active than their cohabiting host foundresses, spent more time at the nest, and rested in the shadowy, back face of the nest, rather than at the front face, which contradicted expectations for the use of space for dominant females—typically, dominants rest at the nest front-face. These data suggest that behavioral adaptations might promote resistance to desiccation stress in chemical insignificant social parasites.
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Affiliation(s)
- Maria Cristina Lorenzi
- Laboratoire d'Ethologie Expérimentale et Comparée, LEEC, UR 4443, Université Sorbonne Paris Nord, F-93430 Villetaneuse, France
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