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Roberts KT, Steward RA, Süess P, Lehmann P, Wheat CW. A time course analysis through diapause reveals dynamic temporal patterns of microRNAs associated with endocrine regulation in the butterfly Pieris napi. Mol Ecol 2024:e17348. [PMID: 38597329 DOI: 10.1111/mec.17348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 03/13/2024] [Accepted: 03/27/2024] [Indexed: 04/11/2024]
Abstract
Organisms inhabiting highly seasonal environments must cope with a wide range of environmentally induced challenges. Many seasonal challenges require extensive physiological modification to survive. In winter, to survive extreme cold and limited resources, insects commonly enter diapause, which is an endogenously derived dormant state associated with minimized cellular processes and low energetic expenditure. Due to the high degree of complexity involved in diapause, substantial cellular regulation is required, of which our understanding primarily derives from the transcriptome via messenger RNA expression dynamics. Here we aim to advance our understanding of diapause by investigating microRNA (miRNA) expression in diapausing and direct developing pupae of the butterfly Pieris napi. We identified coordinated patterns of miRNA expression throughout diapause in both head and abdomen tissues of pupae, and via miRNA target identification, found several expression patterns to be enriched for relevant diapause-related physiological processes. We also identified two candidate miRNAs, miR-14-5p and miR-2a-3p, that are likely involved in diapause progression through their activity in the ecdysone pathway, a critical regulator of diapause termination. miR-14-5p targets phantom, a gene in the ecdysone synthesis pathway, and is upregulated early in diapause. miR-2a-3p has been found to be expressed in response to ecdysone, and is upregulated during diapause termination. Together, the expression patterns of these two miRNAs match our current understanding of the timing of hormonal regulation of diapause in P. napi and provide interesting candidates to further explore the mechanistic role of microRNAs in diapause regulation.
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Affiliation(s)
- Kevin T Roberts
- Department of Zoology, Stockholm University, Stockholm, Sweden
- Zoological Institute and Museum, University of Greifswald, Greifswald, Germany
| | - Rachel A Steward
- Department of Zoology, Stockholm University, Stockholm, Sweden
- Department of Biology, Lund University, Lund, Sweden
| | - Philip Süess
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Philipp Lehmann
- Department of Zoology, Stockholm University, Stockholm, Sweden
- Zoological Institute and Museum, University of Greifswald, Greifswald, Germany
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2
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Lee IHT, Nong W, So WL, Cheung CKH, Xie Y, Baril T, Yip HY, Swale T, Chan SKF, Wei Y, Lo N, Hayward A, Chan TF, Lam HM, Hui JHL. The genome and sex-dependent responses to temperature in the common yellow butterfly, Eurema hecabe. BMC Biol 2023; 21:200. [PMID: 37749565 PMCID: PMC10521528 DOI: 10.1186/s12915-023-01703-1] [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: 12/16/2022] [Accepted: 09/13/2023] [Indexed: 09/27/2023] Open
Abstract
BACKGROUND Lepidoptera (butterflies and moths) is one of the most geographically widespread insect orders in the world, and its species play important and diverse ecological and applied roles. Climate change is one of the biggest challenges to biodiversity this century, and lepidopterans are vulnerable to climate change. Temperature-dependent gene expression differences are of relevance under the ongoing climate crisis. However, little is known about how climate affects gene expression in lepidopterans and the ecological consequences of this, particularly with respect to genes with biased expression in one of the sexes. The common yellow butterfly, Eurema hecabe (Family Pieridae), is one of the most geographically widespread lepidopterans that can be found in Asia, Africa, and Australia. Nevertheless, what temperature-dependent effects there may be and whether the effects differ between the sexes remain largely unexplored. RESULTS Here, we generated high-quality genomic resources for E. hecabe along with transcriptomes from eight developmental stages. Male and female butterflies were subjected to varying temperatures to assess sex-specific gene expression responses through mRNA and microRNA transcriptomics. We find that there are more temperature-dependent sex-biased genes in females than males, including genes that are involved in a range of biologically important functions, highlighting potential ecological impacts of increased temperatures. Further, by considering available butterfly data on sex-biased gene expression in a comparative genomic framework, we find that the pattern of sex-biased gene expression identified in E. hecabe is highly species-specific, rather than conserved across butterfly species, suggesting that sex-biased gene expression responses to climate change are complex in butterflies. CONCLUSIONS Our study lays the foundation for further understanding of differential responses to environmental stress in a widespread lepidopteran model and demonstrates the potential complexity of sex-specific responses of lepidopterans to climate change.
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Affiliation(s)
- Ivy H T Lee
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | - Wenyan Nong
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | - Wai Lok So
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | - Chris K H Cheung
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | - Yichun Xie
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | | | - Ho Yin Yip
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | | | - Simon K F Chan
- Agriculture, Fisheries and Conservation Department, Hong Kong, China
| | - Yingying Wei
- Department of Statistics, The Chinese University of Hong Kong, Hong Kong, China
| | - Nathan Lo
- School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | | | - Ting Fung Chan
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
| | - Hon-Ming Lam
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | - Jerome H L Hui
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China.
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3
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Teder T, Taits K, Kaasik A, Tammaru T. Limited sex differences in plastic responses suggest evolutionary conservatism of thermal reaction norms: A meta-analysis in insects. Evol Lett 2022; 6:394-411. [PMID: 36579171 PMCID: PMC9783480 DOI: 10.1002/evl3.299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 09/09/2022] [Accepted: 10/05/2022] [Indexed: 11/05/2022] Open
Abstract
Temperature has a profound effect on the growth and development of ectothermic animals. However, the extent to which ecologically driven selection pressures can adjust thermal plastic responses in growth schedules is not well understood. Comparing temperature-induced plastic responses between sexes provides a promising but underexploited approach to evaluating the evolvability of thermal reaction norms: males and females share largely the same genes and immature environments but typically experience different ecological selection pressures. We proceed from the idea that substantial sex differences in plastic responses could be interpreted as resulting from sex-specific life-history optimization, whereas similarity among the sexes should rather be seen as evidence of an essential role of physiological constraints. In this study, we performed a meta-analysis of sex-specific thermal responses in insect development times, using data on 161 species with comprehensive phylogenetic and ecological coverage. As a reference for judging the magnitude of sex specificity in thermal plasticity, we compared the magnitude of sex differences in plastic responses to temperature with those in response to diet. We show that sex-specific responses of development times to temperature variation are broadly similar. We also found no strong evidence for sex specificity in thermal responses to depend on the magnitude or direction of sex differences in development time. Sex differences in temperature-induced plastic responses were systematically less pronounced than sex differences in responses induced by variations in larval diet. Our results point to the existence of substantial constraints on the evolvability of thermal reaction norms in insects as the most likely explanation. If confirmed, the low evolvability of thermal response is an essential aspect to consider in predicting evolutionary responses to climate warming.
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Affiliation(s)
- Tiit Teder
- Department of Zoology, Institute of Ecology and Earth SciencesUniversity of TartuTartuEE‐50409Estonia
- Department of Ecology, Faculty of Environmental SciencesCzech University of Life Sciences PraguePrague165 21Czech Republic
| | - Kristiina Taits
- Department of Zoology, Institute of Ecology and Earth SciencesUniversity of TartuTartuEE‐50409Estonia
| | - Ants Kaasik
- Department of Zoology, Institute of Ecology and Earth SciencesUniversity of TartuTartuEE‐50409Estonia
| | - Toomas Tammaru
- Department of Zoology, Institute of Ecology and Earth SciencesUniversity of TartuTartuEE‐50409Estonia
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4
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Pruisscher P, Lehmann P, Nylin S, Gotthard K, Wheat CW. Extensive transcriptomic profiling of pupal diapause in a butterfly reveals a dynamic phenotype. Mol Ecol 2021; 31:1269-1280. [PMID: 34862690 DOI: 10.1111/mec.16304] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 12/13/2022]
Abstract
Diapause is a common adaptation for overwintering in insects that is characterized by arrested development and increased tolerance to stress and cold. While the expression of specific candidate genes during diapause have been investigated, there is no general understanding of the dynamics of the transcriptional landscape as a whole during the extended diapause phenotype. Such a detailed temporal insight is important as diapause is a vital aspect of life cycle timing. Here, we performed a time-course experiment using RNA-Seq on the head and abdomen in the butterfly Pieris napi. In both body parts, comparing diapausing and nondiapausing siblings, differentially expressed genes are detected from the first day of pupal development and onwards, varying dramatically across these formative stages. During diapause there are strong gene expression dynamics present, revealing a preprogrammed transcriptional landscape that is active during the winter. Different biological processes appear to be active in the two body parts. Finally, adults emerging from either the direct or diapause pathways do not show large transcriptomic differences, suggesting the adult phenotype is strongly canalized.
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Affiliation(s)
| | - Philipp Lehmann
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Sören Nylin
- Department of Zoology, Stockholm University, Stockholm, Sweden
| | - Karl Gotthard
- Department of Zoology, Stockholm University, Stockholm, Sweden
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5
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Moradinour Z, Wiklund C, Jie VW, Restrepo CE, Gotthard K, Miettinen A, Perl CD, Baird E. Sensory Organ Investment Varies with Body Size and Sex in the Butterfly Pieris napi. INSECTS 2021; 12:insects12121064. [PMID: 34940152 PMCID: PMC8707955 DOI: 10.3390/insects12121064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/23/2021] [Accepted: 11/25/2021] [Indexed: 11/16/2022]
Abstract
In solitary insect pollinators such as butterflies, sensory systems must be adapted for multiple tasks, including nectar foraging, mate-finding, and locating host-plants. As a result, the energetic investments between sensory organs can vary at the intraspecific level and even among sexes. To date, little is known about how these investments are distributed between sensory systems and how it varies among individuals of different sex. We performed a comprehensive allometric study on males and females of the butterfly Pieris napi where we measured the sizes and other parameters of sensory traits including eyes, antennae, proboscis, and wings. Our findings show that among all the sensory traits measured, only antenna and wing size have an allometric relationship with body size and that the energetic investment in different sensory systems varies between males and females. Moreover, males had absolutely larger antennae and eyes, indicating that they invest more energy in these organs than females of the same body size. Overall, the findings of this study reveal that the size of sensory traits in P. napi are not necessarily related to body size and raises questions about other factors that drive sensory trait investment in this species and in other insect pollinators in general.
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Affiliation(s)
- Zahra Moradinour
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden; (C.W.); (V.W.J.); (C.E.R.); (K.G.); (C.D.P.); (E.B.)
- Correspondence:
| | - Christer Wiklund
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden; (C.W.); (V.W.J.); (C.E.R.); (K.G.); (C.D.P.); (E.B.)
| | - Vun Wen Jie
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden; (C.W.); (V.W.J.); (C.E.R.); (K.G.); (C.D.P.); (E.B.)
| | - Carlos E. Restrepo
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden; (C.W.); (V.W.J.); (C.E.R.); (K.G.); (C.D.P.); (E.B.)
| | - Karl Gotthard
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden; (C.W.); (V.W.J.); (C.E.R.); (K.G.); (C.D.P.); (E.B.)
| | - Arttu Miettinen
- Swiss Light Source, Paul Scherrer Institute, 5234 Villigen, Switzerland;
- Department of Physics, University of Jyvaskyla, 40014 Jyvaskyla, Finland
| | - Craig D. Perl
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden; (C.W.); (V.W.J.); (C.E.R.); (K.G.); (C.D.P.); (E.B.)
- Department of Biology, Lund University, 223 62 Lund, Sweden
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Emily Baird
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden; (C.W.); (V.W.J.); (C.E.R.); (K.G.); (C.D.P.); (E.B.)
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Wiklund C, Wickman PO, Nylin S. A SEX DIFFERENCE IN THE PROPENSITY TO ENTER DIRECT/DIAPAUSE DEVELOPMENT: A RESULT OF SELECTION FOR PROTANDRY. Evolution 2017; 46:519-528. [PMID: 28564039 DOI: 10.1111/j.1558-5646.1992.tb02055.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/1990] [Accepted: 08/16/1991] [Indexed: 11/28/2022]
Abstract
In monandrous mating systems with discrete nonoverlapping generations males should maximize the expected number of matings by starting to emerge before females. This is known as protandry. Moreover, Evolutionarily Stable Strategies (ESS) models show that the male emergence curve should be abruptly truncated before female emergence has ceased. In temperate areas where many insects have partial second generations, we accordingly predict that males should enter diapause development at an earlier date than should females, as a result of late-emerging males being penalized in terms of fewer mating opportunities. The decision to diapause or to develop directly is usually mediated by response to environmental stimuli of which day length is the most important. Hence we predict that the mechanism by which males enter diapause at an earlier date than females will be that of the male reaction norm for diapause development being shifted towards longer day lengths when compared to that of females. As a result of the greater tendency of males to enter diapause development, partial second generations that develop directly should be female biased. As a corollary, first generations should be male biased because some males of the first generation are from the previous year. The prediction that males should enter diapause development earlier in the season, i.e., at longer day lengths, as compared to females was corroborated by rearing Pieris napi under a variety of critical day length regimes producing mixed broods of directly developing and diapausing individuals, and by outdoor rearings of cohorts of larvae of P. napi and P. rapae initiated throughout the season. The prediction that partial second generations should be female biased was corroborated by laboratory rearings at constant temperature of P. napi (Pieridae), Polygonia c-album (Nymphalidae), and Pararge aegeria (Satyridae) under critical day length conditions, producing female-biased sex ratio under direct, and male-biased sex ratio under diapause development.
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Affiliation(s)
- Christer Wiklund
- Department of Zoology, University of Stockholm, S 10691, Stockholm, SWEDEN
| | - Per-Olof Wickman
- Department of Zoology, University of Stockholm, S 10691, Stockholm, SWEDEN
| | - Sören Nylin
- Department of Zoology, University of Stockholm, S 10691, Stockholm, SWEDEN
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7
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Stålhandske S, Lehmann P, Pruisscher P, Leimar O. Effect of winter cold duration on spring phenology of the orange tip butterfly, Anthocharis cardamines. Ecol Evol 2015; 5:5509-20. [PMID: 27069602 PMCID: PMC4813107 DOI: 10.1002/ece3.1773] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 09/04/2015] [Accepted: 09/17/2015] [Indexed: 11/09/2022] Open
Abstract
The effect of spring temperature on spring phenology is well understood in a wide range of taxa. However, studies on how winter conditions may affect spring phenology are underrepresented. Previous work on Anthocharis cardamines (orange tip butterfly) has shown population‐specific reaction norms of spring development in relation to spring temperature and a speeding up of post‐winter development with longer winter durations. In this experiment, we examined the effects of a greater and ecologically relevant range of winter durations on post‐winter pupal development of A. cardamines of two populations from the United Kingdom and two from Sweden. By analyzing pupal weight loss and metabolic rate, we were able to separate the overall post‐winter pupal development into diapause duration and post‐diapause development. We found differences in the duration of cold needed to break diapause among populations, with the southern UK population requiring a shorter duration than the other populations. We also found that the overall post‐winter pupal development time, following removal from winter cold, was negatively related to cold duration, through a combined effect of cold duration on diapause duration and on post‐diapause development time. Longer cold durations also lead to higher population synchrony in hatching. For current winter durations in the field, the A. cardamines population of southern UK could have a reduced development rate and lower synchrony in emergence because of short winters. With future climate change, this might become an issue also for other populations. Differences in winter conditions in the field among these four populations are large enough to have driven local adaptation of characteristics controlling spring phenology in response to winter duration. The observed phenology of these populations depends on a combination of winter and spring temperatures; thus, both must be taken into account for accurate predictions of phenology.
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Affiliation(s)
| | - Philipp Lehmann
- Department of Zoology Stockholm University 106 91 Stockholm Sweden
| | - Peter Pruisscher
- Department of Zoology Stockholm University 106 91 Stockholm Sweden
| | - Olof Leimar
- Department of Zoology Stockholm University 106 91 Stockholm Sweden
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8
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Latitudinal variation in diapause duration and post-winter development in two pierid butterflies in relation to phenological specialization. Oecologia 2014; 177:181-90. [PMID: 25362581 DOI: 10.1007/s00442-014-3125-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/15/2014] [Indexed: 10/24/2022]
Abstract
Diapause plays a central role in insect life cycles by allowing survival during adverse seasonal conditions as well as synchronizing life cycles with the period of mate and food availability. Seasonal timing is expected to be particularly important for species that are dependent on resources available during a short time window-so-called phenological specialists-and latitudinal clines in seasonality are expected to favor local adaptation in phenological timing. However, to what degree latitudinal variation in diapause dynamics and post-winter development due to such local adaptation is influenced by the degree of phenological specialization is not well known. We experimentally studied two pierid butterfly species and found that the phenological specialist Anthocharis cardamines had shorter diapause duration than the phenological generalist Pieris napi along a latitudinal gradient in Sweden. Moreover, diapause duration increased with latitude in P. napi but not in A. cardamines. Sensitivity of the two species to winter thermal conditions also differed; additional cold temperature during the winter period shortened diapause duration for P. napi pupae but not for A. cardamines pupae. In both species, post-winter pupal development was faster after longer periods of cold conditions, and more southern populations developed faster than northern populations. Post-winter development was also invariably faster at higher temperatures in both species. We argue that the observed differences in diapause dynamics between the two species might be explained by the difference in phenological specialization that influences the costs of breaking diapause too early in the season.
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Posledovich D, Toftegaard T, Navarro-Cano JA, Wiklund C, Ehrlén J, Gotthard K. Latitudinal variation in thermal reaction norms of post-winter pupal development in two butterflies differing in phenological specialization. Biol J Linn Soc Lond 2014. [DOI: 10.1111/bij.12371] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Diana Posledovich
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
| | - Tenna Toftegaard
- Department of Ecology, Environment and Plant Sciences; Stockholm University; 106 91 Stockholm Sweden
| | - Jose A. Navarro-Cano
- Department of Ecology, Environment and Plant Sciences; Stockholm University; 106 91 Stockholm Sweden
| | - Christer Wiklund
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
| | - Johan Ehrlén
- Department of Ecology, Environment and Plant Sciences; Stockholm University; 106 91 Stockholm Sweden
| | - Karl Gotthard
- Department of Zoology; Stockholm University; 106 91 Stockholm Sweden
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10
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Nylin S. Induction of diapause and seasonal morphs in butterflies and other insects: knowns, unknowns and the challenge of integration. PHYSIOLOGICAL ENTOMOLOGY 2013; 38:96-104. [PMID: 23894219 PMCID: PMC3712473 DOI: 10.1111/phen.12014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/16/2013] [Indexed: 05/26/2023]
Abstract
The 'choice' of whether to enter diapause or to develop directly has profound effects on the life histories of insects, and may thus have cascading consequences such as seasonal morphs and other less obvious forms of seasonal plasticity. Present knowledge of the control of diapause and seasonal morphs at the physiological and molecular levels is briefly reviewed. Examples, mainly derived from personal research (primarily on butterflies), are given as a starting point with the aim of outlining areas of research that are still poorly understood. These include: the role of the direction of change in photoperiod; the role of factors such as temperature and diet in modifying the photoperiodic responses; and the role of sex, parental effects and sex linkage on photoperiodic control. More generally, there is still a limited understanding of how external cues and physiological pathways regulating various traits are interconnected via gene action to form a co-adapted complete phenotype that is adaptive in the wild despite environmental fluctuation and change.
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Affiliation(s)
- Sören Nylin
- Department of Zoology, Stockholm University Stockholm, Sweden
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11
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Tabadkani SM, Ashouri A, Qolizadeh M. An equal sex ratio followed by differential sex mortality causes overestimation of females in gall midges: no evidence for sex ratio regulation. Naturwissenschaften 2012; 99:493-9. [PMID: 22643882 DOI: 10.1007/s00114-012-0925-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/10/2012] [Accepted: 05/12/2012] [Indexed: 11/25/2022]
Abstract
Monogeny, the production of unisexual broods by individual females, has been recognized for nearly 80 years. The genetic nature of gall midges' sex determination predicts an equal numbers of male-producing and female-producing females in the populations such that the overall sex ratio is expected to be nearly 1:1. However, observations of some strictly monogenous populations with biased sex ratio, mainly toward females, have raised the question of whether gall midges are able to adjust their offspring sex ratio in response to changes in environmental conditions, and some authors have even considered sex ratio regulation as a strong force in the course of the evolution of monogeny. In this paper, first, by studying the sex ratio variations of the predatory gall midge, Aphidoletes aphidimyza within a generation, we showed that adult males emerge up to 1 day earlier and have shorter life span than females (less than 4 days and up to 6 days, respectively). Although, the sex ratio of A. aphidimyza at the time of emergence was nearly 1:1 (52.41% males), a simple population simulation indicated that the differential mortality of sexes can lead to a female-biased sex ratio estimation (57.88% females) under random sampling in the natural environments. Our results imply that the primary sex ratio of monogenous gall midges is nearly 1:1 and that the arrhenogenic/thelygenic gall midges are not able to alter the number of their male/female progenies in response to changes in environmental conditions.
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Affiliation(s)
- Seyed Mohammad Tabadkani
- Department of Plant Protection, College of Horticulture and Plant Protection, Faculty of Agriculture and Natural Resources, University of Tehran, PO Box 4111, Karaj, Iran.
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12
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Larsdotter-Mellström H, Murtazina R, Borg-Karlson AK, Wiklund C. Timing of male sex pheromone biosynthesis in a butterfly - different dynamics under direct or diapause development. J Chem Ecol 2012; 38:584-91. [PMID: 22555771 DOI: 10.1007/s10886-012-0126-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 04/13/2012] [Accepted: 04/17/2012] [Indexed: 11/30/2022]
Abstract
The life history traits and behavior of the butterfly Pieris napi are well-known, as the species is often used as a model organism for evolutionary and ecological studies. The species has two or more generations per year in the major part of its temperate distribution, and as different selection pressures affect the different generations, both behavioral and physiological seasonal polyphenisms have been shown previously. Here, we explored the dynamics of male sex pheromone production. The two generations are shown to have significantly different scent compositions early in life; the direct developers--who have shorter time for pupal development--need the first 24 hr of adult life after eclosion to synthesize the sex pheromone citral (geranial and neral 1:1)--whereas the diapausing individuals who have spent several months in the pupal stage eclose with adult scent composition. Resource allocation and biosynthesis also were studied in greater detail by feeding butterflies (13)C labeled glucose either in the larval or adult stage, and recording incorporation into geranial, neral, and other volatiles produced. Results demonstrate that the pheromone synthesized by newly eclosed adult males is based on materials ingested in the larval stage, and that adult butterflies are able to synthesize the pheromone components geranial and neral and the related alcohols also from adult intake of glucose. In summary, our study shows that time-stress changes the timing in biosynthesis of the complete pheromone between generations, and underpins the importance of understanding resource allocation and the physiological basis of life history traits.
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Larsdotter Mellström H, Friberg M, Borg-Karlson AK, Murtazina R, Palm M, Wiklund C. Seasonal polyphenism in life history traits: time costs of direct development in a butterfly. Behav Ecol Sociobiol 2010. [DOI: 10.1007/s00265-010-0952-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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14
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Karlsson B, Johansson A. Seasonal polyphenism and developmental trade-offs between flight ability and egg laying in a pierid butterfly. Proc Biol Sci 2008; 275:2131-6. [PMID: 18522912 DOI: 10.1098/rspb.2008.0404] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Butterflies have competing demands for flight ability depending on, for example, mating system, predation pressure, the localization of host plants and dispersal needs. The flight apparatus, however, is costly to manufacture and therefore trade-offs are expected since resources are limited and must be allocated between flight ability and other functions, such as reproduction. Trade-offs between flight and reproduction may be difficult to reveal since they interact with other factors and can be confounded by differences in resource consumption. Previous studies have shown that adults of the summer generation of Pieris napi have relatively larger thoraxes compared with the spring generation. To study whether difference in thorax size results in a trade-off between flight ability and reproduction among the two generations, we conducted a split-brood experiment under common garden conditions. Our results show that summer generation adults have a higher dispersal capacity measured as flight duration in five different temperatures. Reproductive output differed between the two developmental pathways; spring generation females had a significantly higher output of eggs compared with summer generation females. We suggest that this is a consequence of a resource-allocation trade-off made during pupal development implemented by different demands for flight between the spring and summer generations. The significance of this finding is discussed in relation to reproduction and mobility in butterflies.
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Affiliation(s)
- Bengt Karlsson
- Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden.
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HAYASHI F. Ejaculate production schedule and the degree of protandry in fishflies (Megaloptera: Corydalidae). Funct Ecol 2002. [DOI: 10.1046/j.1365-2435.1999.00289.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- F. HAYASHI
- Department of Biology, Tokyo Metropolitan University, Minamiosawa 1–1, Hachioji, Tokyo 192–0397, Japan
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Bradshaw WE, Holzapfel CM, Kleckner CA, Hard JJ. HERITABILITY OF DEVELOPMENT TIME AND PROTANDRY IN THE PITCHER-PLANT MOSQUITO,WYEOMYIA SMITHII. Ecology 1997. [DOI: 10.1890/0012-9658(1997)078[0969:hodtap]2.0.co;2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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