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Moradinour Z, Wiklund C, Miettinen A, Gérard M, Baird E. Exposure to elevated temperature during development affects eclosion and morphology in the temperate Pieris napi butterfly (Lepidoptera: Pieridae). J Therm Biol 2023; 118:103721. [PMID: 38016229 DOI: 10.1016/j.jtherbio.2023.103721] [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: 03/01/2023] [Revised: 09/29/2023] [Accepted: 09/29/2023] [Indexed: 11/30/2023]
Abstract
Global warming has been identified as one of the main drivers of population decline in insect pollinators. One aspect of the insect life cycle that would be particularly sensitive to elevated temperatures is the developmental transition from larva to adult. Temperature-induced modifications to the development of body parts and sensory organs likely have functional consequences for adult behaviour. To date, we have little knowledge about the effect of sub-optimal temperature on the development and functional morphology of different body parts, particularly sensory organs, in ectothermic solitary pollinators such as butterflies. To address this knowledge gap, we exposed the pupae of the butterfly Pieris napi to either 23 °C or 32 °C and measured the subsequent effects on eclosion, body size and the development of the wings, proboscis, eyes and antennae. In comparison to individuals that developed at 23 °C, we found that exposure to 32 °C during the pupal stage increased mortality and decreased time to eclose. Furthermore, both female and male butterflies that developed at 32 °C were smaller and had shorter proboscides, while males had shorter antennae. In contrast, we found no significant effect of rearing temperature on wing and eye size or wing deformity. Our findings suggest that increasing global temperatures and its corresponding co-stressors, such as humidity, will impact the survival of butterflies by impairing eclosion and the proper development of body and sensory organs.
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Affiliation(s)
| | | | - Arttu Miettinen
- Institute for Biomedical Engineering, University and ETH Zurich, 8092, Zurich, Switzerland; Swiss Light Source, Paul Scherrer Institute, 5234, Villigen, Switzerland; Department of Physics, University of Jyvaskyla, 40014, Jyvaskyla, Finland
| | - Maxence Gérard
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Emily Baird
- Department of Zoology, Stockholm University, Stockholm, Sweden
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Degut A, Fischer K, Quque M, Criscuolo F, Michalik P, Beaulieu M. Irreversible impact of early thermal conditions: an integrative study of developmental plasticity linked to mobility in a butterfly species. J Exp Biol 2022; 225:273908. [PMID: 34989809 DOI: 10.1242/jeb.243724] [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: 10/29/2021] [Accepted: 12/23/2021] [Indexed: 11/20/2022]
Abstract
Within populations, phenotypic plasticity may allow adaptive phenotypic variation in response to selection generated by environmental heterogeneity. For instance, in multivoltine species, seasonal changes between and within generations may trigger morphological and physiological variation enhancing fitness under different environmental conditions. These seasonal changes may irreversibly affect adult phenotypes when experienced during development. Yet, the irreversible effects of developmental plasticity on adult morphology have rarely been linked to life-history traits even though they may affect different fitness components such as reproduction, mobility and self-maintenance. To address this issue, we raised larvae of Pieris napi butterflies under warm or cool conditions to subsequently compare adult performance in terms of reproduction performance (as assessed through fecundity), displacement capacity (as assessed through flight propensity and endurance) and self-maintenance (as assessed through the measurement of oxidative markers). As expected in ectotherms, individuals developed faster under warm conditions and were smaller than individuals developing under cool conditions. They also had more slender wings and showed a higher wing surface ratio. These morphological differences were associated with changes in the reproductive and flight performances of adults, as individuals developing under warm conditions laid fewer eggs and flew larger distances. Accordingly, the examination of their oxidative status suggested that individuals developing under warm conditions invested more strongly into self-maintenance than individuals developing under cool conditions (possibly at the expense of reproduction). Overall, our results indicate that developmental conditions have long-term consequences on several adult traits in butterflies. This plasticity likely acts on life history strategies for each generation to keep pace with seasonal variations and may facilitate acclimation processes in the context of climate change.
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Affiliation(s)
- Anaïs Degut
- Zoological Institute and Museum, University of Greifswald, Loitzer Str. 26, 17489 Greifswald, Germany
| | - Klaus Fischer
- Zoological Institute and Museum, University of Greifswald, Loitzer Str. 26, 17489 Greifswald, Germany.,Institute for Integrated Sciences, University of Koblenz-Landau, Universität Str. 1, 56070 Koblenz, Germany
| | - Martin Quque
- Institut Pluridisciplinaire Hubert Curien
- IPHC · Department of Ecology, Physiology and Ethology, Strasbourg, France
| | - François Criscuolo
- Institut Pluridisciplinaire Hubert Curien
- IPHC · Department of Ecology, Physiology and Ethology, Strasbourg, France
| | - Peter Michalik
- Zoological Institute and Museum, University of Greifswald, Loitzer Str. 26, 17489 Greifswald, Germany
| | - Michaël Beaulieu
- Zoological Institute and Museum, University of Greifswald, Loitzer Str. 26, 17489 Greifswald, Germany.,German Oceanographic Museum, Katharinenberg 14-20, 18439 Stralsund, Germany
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Liu J, He XZ, Zheng XL, Zhang Y, Wang Q. Pupal Cues Increase Sperm Production but Not Testis Size in an Insect. INSECTS 2021; 12:679. [PMID: 34442245 PMCID: PMC8396453 DOI: 10.3390/insects12080679] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/20/2021] [Accepted: 07/26/2021] [Indexed: 12/13/2022]
Abstract
Theoretic and empirical studies show that social surroundings experienced by male insects during their larval or adult stage can influence their testicular investment in diverse ways. Although insect pupae do not feed and crawl, they can communicate using sex-specific and/or non-sex specific cues. Yet, it is unknown, in any insect, whether and how male pupae can fine-tune their resource allocation to sperm production and testis size in response to socio-sexual environments. We investigated this question using a moth, Ephestia kuehniella, which produces fertile eupyrene sperm and unfertile apyrene sperm. We held male pupae individually or in groups with different sex ratios, and dissected adults upon eclosion, measured their testis size, and counted both types of sperm. We demonstrated that after exposure to conspecific pupal cues regardless of sex, male pupae increased production of eupyrenes and apyrenes at the same rate but kept testis size unchanged. We suggest that testis size is fixed after pupation because most morphological traits are formed during the larval stage, allowing little room for pupae to adjust testis size. Like adults, male pupae with fully grown testes have sufficient resources to produce more sperm of both types according to the perceived increase in sperm competition risk.
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Affiliation(s)
- Junyan Liu
- School of Agriculture and Environment, Massey University, Palmerston North 4410, New Zealand; (J.L.); (X.Z.H.)
| | - Xiong Z. He
- School of Agriculture and Environment, Massey University, Palmerston North 4410, New Zealand; (J.L.); (X.Z.H.)
| | - Xia-Lin Zheng
- Guangxi Key Laboratory of Agric-Environment and Agric-Products Safety, National Demonstration Centre for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning 530004, China; (X.-L.Z.); (Y.Z.)
| | - Yujing Zhang
- Guangxi Key Laboratory of Agric-Environment and Agric-Products Safety, National Demonstration Centre for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning 530004, China; (X.-L.Z.); (Y.Z.)
| | - Qiao Wang
- School of Agriculture and Environment, Massey University, Palmerston North 4410, New Zealand; (J.L.); (X.Z.H.)
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Liu J, He XZ, Zheng XL, Zhang Y, Wang Q. Larval social cues influence testicular investment in an insect. Curr Zool 2021; 68:1-8. [PMID: 35169624 PMCID: PMC8836345 DOI: 10.1093/cz/zoab028] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 03/14/2021] [Indexed: 12/11/2022] Open
Abstract
Socio-sexual environment can have critical impacts on reproduction and survival of animals. Consequently, they need to prepare themselves by allocating more resources to competitive traits that give them advantages in the particular social setting they have been perceiving. Evidence shows that a male usually raises his investment in sperm after he detects the current or future increase of sperm competition because relative sperm numbers can determine his paternity share. This leads to the wide use of testis size as an index of the sperm competition level, yet testis size does not always reflect sperm production. To date, it is not clear whether male animals fine-tune their resource allocation to sperm production and other traits as a response to social cues during their growth and development. Using a polygamous insect Ephestia kuehniella, we tested whether and how larval social environment affected sperm production, testis size, and body weight. We exposed the male larvae to different juvenile socio-sexual cues and measured these traits. We demonstrate that regardless of sex ratio, group-reared males produced more eupyrenes (fertile and nucleate sperm) but smaller testes than singly reared ones, and that body weight and apyrene (infertile and anucleate sperm) numbers remained the same across treatments. We conclude that the presence of larval social, but not sexual cues is responsible for the increase of eupyrene production and decrease of testis size. We suggest that male larvae increase investment in fertile sperm cells and reduce investment in other testicular tissues in the presence of conspecific juvenile cues.
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Affiliation(s)
- Junyan Liu
- School of Agriculture and Environment, Massey University, Palmerston North 4100, New Zealand
| | - Xiong Z He
- School of Agriculture and Environment, Massey University, Palmerston North 4100, New Zealand
| | - Xia-Lin Zheng
- Guangxi Key Laboratory of Agric-Environment and Agric-Products Safety, National Demonstration Centre for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning 530004, China
| | - Yujing Zhang
- Guangxi Key Laboratory of Agric-Environment and Agric-Products Safety, National Demonstration Centre for Experimental Plant Science Education, College of Agriculture, Guangxi University, Nanning 530004, China
| | - Qiao Wang
- School of Agriculture and Environment, Massey University, Palmerston North 4100, New Zealand
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Liu J, Zhang Y, Zheng X, He XZ, Wang Q. Combined cues of male competition influence spermatozoal investment in a moth. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13554] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Junyan Liu
- School of Agriculture and Environment Massey University Palmerston North New Zealand
| | - Yujing Zhang
- Guangxi Key Laboratory of Agric‐Environment and Agric‐Products Safety National Demonstration Center for Experimental Plant Science Education College of Agriculture Guangxi University Nanning China
| | - Xia‐Lin Zheng
- Guangxi Key Laboratory of Agric‐Environment and Agric‐Products Safety National Demonstration Center for Experimental Plant Science Education College of Agriculture Guangxi University Nanning China
| | - Xiong Z. He
- School of Agriculture and Environment Massey University Palmerston North New Zealand
| | - Qiao Wang
- School of Agriculture and Environment Massey University Palmerston North New Zealand
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Kehl T, Dublon IAN, Fischer K. Young male mating success is associated with sperm number but not with male sex pheromone titres. Front Zool 2015; 12:31. [PMID: 26557870 PMCID: PMC4640362 DOI: 10.1186/s12983-015-0124-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 10/27/2015] [Indexed: 11/10/2022] Open
Abstract
Background Intraspecific communication is of crucial importance throughout the animal kingdom and may involve a combination of visual, gustatory, olfactory and acoustic cues. Variation in male sex pheromone amount and composition may convey important information to female conspecifics, for instance on species identity or age. However, whether increased male pheromone titres are associated with fitness benefits for the female, thus indicating a role as an honest signal, is under debate. Results Against this background, we tested in the butterfly Bicyclus anynana (1) whether young males being successful or unsuccessful in gaining a mating differed in sex pheromone titres and (2) for associations between male pheromone titres and spermatophore mass, eupyrene sperm number, and a variety of female and offspring life-history traits. Successful and unsuccessful males did not differ in pheromone titres, however eupyrene sperm number was much higher in successful males. Pheromone titres were not associated with any fitness-related female or offspring trait measured in our study, though correlation analyses yielded evidence for trade-offs among specific traits. Patterns did not differ among control and olfaction-blocked females. Conclusion Therefore, we suggest that in young B. anynana pheromone titres do not indicate male quality.
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Affiliation(s)
- Tobias Kehl
- Zoological Institute & Museum, Greifswald University, Johann-Sebastian-Bach Str. 11/12, Greifswald, 17489 Germany
| | - Ian A N Dublon
- Evolutionary Ecology and Genetics Group, Biodiversity Research Centre, Earth and Life Institute, Université catholique de Louvain (UCL), Croix du Sud 4, Louvain-la-Neuve, 1348 Belgium
| | - Klaus Fischer
- Zoological Institute & Museum, Greifswald University, Johann-Sebastian-Bach Str. 11/12, Greifswald, 17489 Germany
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