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Brülhart J, Süß A, Oettler J, Heinze J, Schultner E. Sex- and caste-specific developmental responses to juvenile hormone in an ant with maternal caste determination. J Exp Biol 2024; 227:jeb247396. [PMID: 38779857 DOI: 10.1242/jeb.247396] [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: 01/25/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
Juvenile hormone is considered to be a master regulator of polyphenism in social insects. In the ant Cardiocondyla obscurior, whether a female egg develops into a queen or a worker is determined maternally and caste-specific differentiation occurs in embryos, so that queens and workers can be distinguished in a non-invasive manner from late embryogenesis onwards. This ant also exhibits two male morphs - winged and wingless males. Here, we used topical treatment with juvenile hormone III and its synthetic analogue methoprene, a method that influences caste determination and differentiation in some ant species, to investigate whether hormone manipulation affects the development and growth of male, queen- and worker-destined embryos and larvae. We found no effect of hormone treatment on female caste ratios or body sizes in any of the treated stages, even though individuals reacted to heightened hormone availability with increased expression of krüppel-homolog 1, a conserved JH first-response gene. In contrast, hormone treatment resulted in the emergence of significantly larger males, although male morph fate was not affected. These results show that in C. obscurior, maternal caste determination leads to irreversible and highly canalized caste-specific development and growth.
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Affiliation(s)
- Jeanne Brülhart
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Anja Süß
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Jan Oettler
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Jürgen Heinze
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Eva Schultner
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93053 Regensburg, Germany
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2
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Schultner E, Wallner T, Dofka B, Brülhart J, Heinze J, Freitak D, Pokorny T, Oettler J. Queens control caste allocation in the ant Cardiocondyla obscurior. Proc Biol Sci 2023; 290:20221784. [PMID: 36750190 PMCID: PMC9904955 DOI: 10.1098/rspb.2022.1784] [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: 09/08/2022] [Accepted: 01/17/2023] [Indexed: 02/09/2023] Open
Abstract
Social insect queens and workers can engage in conflict over reproductive allocation when they have different fitness optima. Here, we show that queens have control over queen-worker caste allocation in the ant Cardiocondyla obscurior, a species in which workers lack reproductive organs. We describe crystalline deposits that distinguish castes from the egg stage onwards, providing the first report of a discrete trait that can be used to identify ant caste throughout pre-imaginal development. The comparison of queen and worker-destined eggs and larvae revealed size and weight differences in late development, but no discernible differences in traits that may be used in social interactions, including hair morphology and cuticular odours. In line with a lack of caste-specific traits, adult workers treated developing queens and workers indiscriminately. Together with previous studies demonstrating queen control over sex allocation, these results show that queens control reproductive allocation in C. obscurior and suggest that the fitness interests of colony members are aligned to optimize resource allocation in this ant.
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Affiliation(s)
- Eva Schultner
- Zoology/Evolutionary Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Tobias Wallner
- Zoology/Evolutionary Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Benjamin Dofka
- Zoology/Evolutionary Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Jeanne Brülhart
- Zoology/Evolutionary Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Jürgen Heinze
- Zoology/Evolutionary Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Dalial Freitak
- Institute for Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Tamara Pokorny
- Zoology/Evolutionary Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Jan Oettler
- Zoology/Evolutionary Biology, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
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3
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Errbii M, Keilwagen J, Hoff KJ, Steffen R, Altmüller J, Oettler J, Schrader L. Transposable elements and introgression introduce genetic variation in the invasive ant Cardiocondyla obscurior. Mol Ecol 2021; 30:6211-6228. [PMID: 34324751 DOI: 10.1111/mec.16099] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 12/11/2022]
Abstract
Introduced populations of invasive organisms have to cope with novel environmental challenges, while having reduced genetic variation caused by founder effects. The mechanisms associated with this "genetic paradox of invasive species" has received considerable attention, yet few studies have examined the genomic architecture of invasive species. Populations of the heart node ant Cardiocondyla obscurior belong to two distinct lineages, a New World lineage so far only found in Latin America and a more globally distributed Old World lineage. In the present study, we use population genomic approaches to compare populations of the two lineages with apparent divergent invasive potential. We find that the strong genetic differentiation of the two lineages began at least 40,000 generations ago and that activity of transposable elements (TEs) has contributed significantly to the divergence of both lineages, possibly linked to the very unusual genomic distribution of TEs in this species. Furthermore, we show that introgression from the Old World lineage is a dominant source of genetic diversity in the New World lineage, despite the lineages' strong genetic differentiation. Our study uncovers mechanisms underlying novel genetic variation in introduced populations of C. obscurior that could contribute to the species' adaptive potential.
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Affiliation(s)
- Mohammed Errbii
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
| | - Jens Keilwagen
- Institute for Biosafety in Plant Biotechnology, Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Quedlinburg, Germany
| | - Katharina J Hoff
- Institute of Mathematics and Computer Science, University of Greifswald, Greifswald, Germany.,Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Raphael Steffen
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
| | - Janine Altmüller
- Cologne Center for Genomics, Institute of Human Genetics, University of Cologne, Cologne, Germany.,Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Core Facility Genomics, Berlin, Germany.,Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Jan Oettler
- Lehrstuhl für Zoologie/Evolutionsbiologie, University Regensburg, Regensburg, Germany
| | - Lukas Schrader
- Institute for Evolution and Biodiversity, University of Münster, Münster, Germany
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4
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Heinze J, Marschall J, Lautenschläger B, Seifert B, Gratiashvili N, Strohm E. Courtship with two spoons-Anatomy and presumed function of the bizarre antennae of Cardiocondyla zoserka ant males. Ecol Evol 2021; 11:7827-7833. [PMID: 34188854 PMCID: PMC8216964 DOI: 10.1002/ece3.7615] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/01/2021] [Accepted: 04/09/2021] [Indexed: 11/06/2022] Open
Abstract
Mating in ants often occurs on the wing during nuptial flights or on the ground when scattered female sexuals attract males by pheromones. In both scenarios, there is little opportunity for males to engage in prolonged aggressive competition or elaborate courtship displays. Male morphology is therefore adapted to locating female sexuals and mating, and it lacks specific weapons or other traits associated with courtship. In contrast, sexuals of the ant genus Cardiocondyla typically mate in their natal nests. As a consequence, in many species winged males have been replaced by wingless fighter or territorial males, which kill or expel rival males with their strong mandibles and show complex mating behavior. However, no wingless males are known from Cardiocondyla zoserka from West Africa, and instead, winged males have evolved a bizarre secondary sexual trait: uniquely shaped antennae with spoon-like tips that show heavily sculptured ventral surfaces with numerous invaginations. We here report on the courtship behavior of C. zoserka males and describe antennal glands with class 3 gland cells, which presumably secrete a close range sex pheromone. Antennal glands have not yet been found in males of other ant species, including a close relative of C. zoserka, suggesting that in ants with intranidal mating sexual selection can rapidly lead to highly divergent adaptations and the evolution of novel structures.
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Affiliation(s)
- Jürgen Heinze
- LS Zoology/Evolutionary BiologyUniversität RegensburgRegensburgGermany
| | - Jella Marschall
- LS Zoology/Evolutionary BiologyUniversität RegensburgRegensburgGermany
| | | | | | | | - Erhard Strohm
- LS Zoology/Evolutionary BiologyUniversität RegensburgRegensburgGermany
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5
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Vidal M, Königseder F, Giehr J, Schrempf A, Lucas C, Heinze J. Worker ants promote outbreeding by transporting young queens to alien nests. Commun Biol 2021; 4:515. [PMID: 33941829 PMCID: PMC8093424 DOI: 10.1038/s42003-021-02016-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/22/2021] [Indexed: 11/09/2022] Open
Abstract
Choosing the right mating partner is one of the most critical decisions in the life of a sexually reproducing organism and is the basis of sexual selection. This choice is usually assumed to be made by one or both of the sexual partners. Here, we describe a system in which a third party – the siblings – promote outbreeding by their sisters: workers of the tiny ant Cardiocondyla elegans carry female sexuals from their natal nest over several meters and drop them in the nest of another, unrelated colony to promote outbreeding with wingless, stationary males. Workers appear to choose particular recipient colonies into which they transfer numerous female sexuals. Assisted outbreeding and indirect female choice in the ant C. elegans are comparable to human matchmaking and suggest a hitherto unknown aspect of natural history – third party sexual selection. Our study highlights that research at the intersection between social evolution and reproductive biology might reveal surprising facets of animal behavior. Vidal et al. identify a breeding system in the ant Cardiocondyla elegans that avoids colonial inbreeding, managed by a third party of worker ants. This system bears similarities to human matchmaking, but with fundamental genetic drivers rather than social ones.
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Affiliation(s)
- Mathilde Vidal
- Chair of Zoology and Evolutionary Biology - University of Regensburg, Regensburg, Germany.
| | - Florian Königseder
- Chair of Zoology and Evolutionary Biology - University of Regensburg, Regensburg, Germany
| | - Julia Giehr
- Chair of Zoology and Evolutionary Biology - University of Regensburg, Regensburg, Germany
| | - Alexandra Schrempf
- Chair of Zoology and Evolutionary Biology - University of Regensburg, Regensburg, Germany
| | - Christophe Lucas
- Institut de Recherche sur la Biologie de l'Insecte (UMR7261), CNRS - Université de Tours, Tours, France
| | - Jürgen Heinze
- Chair of Zoology and Evolutionary Biology - University of Regensburg, Regensburg, Germany
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6
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Liotta MN, Abbott JK, Morris MR, Rios‐Cardenas O. Antagonistic selection on body size and sword length in a wild population of the swordtail fish, Xiphophorus multilineatus: Potential for intralocus tactical conflict. Ecol Evol 2021; 11:3941-3955. [PMID: 33976786 PMCID: PMC8093718 DOI: 10.1002/ece3.7288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/08/2021] [Accepted: 01/18/2021] [Indexed: 11/06/2022] Open
Abstract
Alternative reproductive tactics (ARTs) have provided valuable insights into how sexual selection and life history trade-offs can lead to variation within a sex. However, the possibility that tactics may constrain evolution through intralocus tactical conflict (IATC) is rarely considered. In addition, when IATC has been considered, the focus has often been on the genetic correlations between the ARTs, while evidence that the ARTs have different optima for associated traits and that at least one of the tactics is not at its optimum is often missing. Here, we investigate selection on three traits associated with the ARTs in the swordtail fish Xiphophorus multilineatus; body size, body shape, and the sexually selected trait for which these fishes were named, sword length (elongation of the caudal fin). All three traits are tactically dimorphic, with courter males being larger, deeper bodied and having longer swords, and the sneaker males being smaller, more fusiform and having shorter swords. Using measures of reproductive success in a wild population we calculated selection differentials, as well as linear and quadratic gradients. We demonstrated that the tactics have different optima and at least one of the tactics is not at its optimum for body size and sword length. Our results provide the first evidence of selection in the wild on the sword, an iconic trait for sexual selection. In addition, given the high probability that these traits are genetically correlated to some extent between the two tactics, our study suggests that IATC is constraining both body size and the sword from reaching their phenotypic optima. We discuss the importance of considering the role of IATC in the evolution of tactical dimorphism, how this conflict can be present despite tactical dimorphism, and how it is important to consider this conflict when explaining not only variation within a species but differences across species as well.
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Affiliation(s)
- Melissa N. Liotta
- Department of Biological SciencesThe Ohio Center for Ecological and Evolutionary StudiesOhio UniversityAthensOHUSA
| | | | - Molly R. Morris
- Department of Biological SciencesThe Ohio Center for Ecological and Evolutionary StudiesOhio UniversityAthensOHUSA
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7
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Hanna L, Abouheif E. The origin of wing polyphenism in ants: An eco-evo-devo perspective. Curr Top Dev Biol 2021; 141:279-336. [PMID: 33602491 DOI: 10.1016/bs.ctdb.2020.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The evolution of eusociality, where solitary individuals integrate into a single colony, is a major transition in individuality. In ants, the origin of eusociality coincided with the origin of a wing polyphenism approximately 160 million years ago, giving rise to colonies with winged queens and wingless workers. As a consequence, both eusociality and wing polyphenism are nearly universal features of all ants. Here, we synthesize fossil, ecological, developmental, and evolutionary data in an attempt to understand the factors that contributed to the origin of wing polyphenism in ants. We propose multiple models and hypotheses to explain how wing polyphenism is orchestrated at multiple levels, from environmental cues to gene networks. Furthermore, we argue that the origin of wing polyphenism enabled the subsequent evolution of morphological diversity across the ants. We finally conclude by outlining several outstanding questions for future work.
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Affiliation(s)
- Lisa Hanna
- Department of Biology, McGill University, Montreal, QC, Canada
| | - Ehab Abouheif
- Department of Biology, McGill University, Montreal, QC, Canada.
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8
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Gratiashvili N, Kuschel L, Heinze J. Morphometry and colony structure of ants of the genus Cardiocondyla (Hymenoptera: Formicidae) from Georgia. ZOOLOGY IN THE MIDDLE EAST 2020. [DOI: 10.1080/09397140.2020.1835216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
| | - Lena Kuschel
- Zoology/Evolutionary Biology, University of Regensburg, Regensburg, Germany
| | - Jürgen Heinze
- Zoology/Evolutionary Biology, University of Regensburg, Regensburg, Germany
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9
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Abbott J, Rios‐Cardenas O, Morris MR. Insights from intralocus tactical conflict: adaptive states, interactions with ecology and population divergence. OIKOS 2019. [DOI: 10.1111/oik.06264] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Jessica Abbott
- Section for Evolutionary Ecology, Dept of Biology, Univ. Of Lund Sölvegatan 37 SE‐223 62 Lund Swede
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10
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Heinze J, Hölldobler B. Insect harem polygyny—the case of Cardiocondyla ants: a comment on Griffin et al. (2019). Behav Ecol Sociobiol 2019. [DOI: 10.1007/s00265-019-2718-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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11
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Jacobs S, Heinze J. Population and colony structure of an ant with territorial males, Cardiocondyla venustula. BMC Evol Biol 2019; 19:115. [PMID: 31170910 PMCID: PMC6551906 DOI: 10.1186/s12862-019-1448-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 05/28/2019] [Indexed: 01/28/2023] Open
Abstract
Background Many species of social insects have large-scale mating and dispersal flights and their populations are therefore often relatively homogenous. In contrast, dispersal on the wing appears to be uncommon in most species of the ant genus Cardiocondyla, because its males are wingless and the winged queens mate in their natal nests before dispersing on foot. Here we examine the population structure of C. venustula from South Africa. This species is of particular interest for the analysis of life history evolution in Cardiocondyla, as it occupies a phylogenetic position between tropical species with multi-queen (polygynous) colonies and fighting males and a Palearctic clade with single-queen colonies and mutually peaceful males. Males of C. venustula exhibit an intermediate strategy between lethal fighting and complete tolerance – they mostly engage in non-lethal fights and defend small territories inside their natal nests. We investigated how this reproductive behavior influences colony and population structure by analyzing samples on two geographic scales in South Africa: a small 40 × 40m2 plot and a larger area with distances up to 5 km between sampling sites in Rietvlei Nature Reserve near Pretoria. Results Colonies were found to be facultatively polygynous and queens appear to mate only with a single male. The extraordinarily high inbreeding coefficient suggests regular sib-mating. Budding by workers and young queens is the predominant mode of colony-founding and leads to high population viscosity. In addition, some queens appear to found colonies independently or through adoption into foreign nests. Conclusion While C. venustula resembles tropical Cardiocondyla in queen number and mating frequency, it differs by the absence of winged disperser males. Dispersal by solitary, mated queens on foot or by short flights and their adoption by alien colonies might promote gene flow between colonies and counteract prolonged inbreeding. The abundance of suitable habitat and the high density of nests facilitate the spread of this species by budding and together with the apparent resistance against inbreeding make it a highly successful pioneer species and invader of degraded and man-made habitats. Electronic supplementary material The online version of this article (10.1186/s12862-019-1448-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Susanne Jacobs
- Zoology / Evolutionary Biology, Universität Regensburg, 93040, Regensburg, Germany
| | - Jürgen Heinze
- Zoology / Evolutionary Biology, Universität Regensburg, 93040, Regensburg, Germany.
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12
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Oettler J, Platschek T, Schmidt C, Rajakumar R, Favé MJ, Khila A, Heinze J, Abouheif E. Interruption points in the wing gene regulatory network underlying wing polyphenism evolved independently in male and female morphs in Cardiocondyla ants. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2018; 332:7-16. [PMID: 30460750 DOI: 10.1002/jez.b.22834] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 10/18/2018] [Indexed: 11/10/2022]
Abstract
Wing polyphenism in ants, which produces a winged female queen caste and a wingless female worker caste, evolved approximately 150 million years ago and has been key to the remarkable success of ants. Approximately 20 million years ago, the myrmicine ant genus Cardiocondyla evolved an additional wing polyphenism among males producing two male morphs: wingless males that fight to enhance mating success and winged males that disperse. Here we show that interruption of rudimentary wing-disc development in larvae of the ant Cardiocondyla obscurior occurs further downstream in the network in wingless males as compared with wingless female workers. This pattern is corroborated in C. kagutsuchi, a species from a different clade within the genus, indicating that late interruption of wing development in males is conserved across Cardiocondyla. Therefore, our results show that the novel male wing polyphenism was not developmentally constrained by the pre-existing female wing polyphenism and evolved through independent alteration of interruption points in the wing gene network. Furthermore, a comparison of adult morphological characters in C. obscurior reveals that developmental trajectories lead to similar morphological trait integration between winged and wingless females, but dramatically different integration between winged and wingless males. This suggests that the alternative sex-specific developmental routes to achieve winglessness in the genus Cardiocondyla may have evolved through different selection regimes acting on wingless males and females.
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Affiliation(s)
- Jan Oettler
- Zoologie-Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
| | - Tobias Platschek
- Zoologie-Evolutionsbiologie, Universität Regensburg, Regensburg, Germany.,Department of Biology, McGill University, Montreal, Quebec, Canada
| | - Christine Schmidt
- Zoologie-Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
| | | | - Marie-Julie Favé
- Department of Biology, McGill University, Montreal, Quebec, Canada
| | | | - Jürgen Heinze
- Zoologie-Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
| | - Ehab Abouheif
- Department of Biology, McGill University, Montreal, Quebec, Canada
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13
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Heinze J. Life-history evolution in ants: the case of Cardiocondyla. Proc Biol Sci 2018; 284:rspb.2016.1406. [PMID: 28298341 DOI: 10.1098/rspb.2016.1406] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/06/2016] [Indexed: 01/09/2023] Open
Abstract
Ants are important components of most terrestrial habitats, and a better knowledge of the diversity of their life histories is essential to understand many aspects of ecosystem functioning. The myrmicine genus Cardiocondyla shows a wide range of colony structures, reproductive behaviours, queen and male lifespans, and habitat use. Reconstructing the evolutionary pathways of individual and social phenotypic traits suggests that the ancestral life history of Cardiocondyla was characterized by the presence of multiple, short-lived queens in small-sized colonies and a male polyphenism with winged dispersers and wingless fighters, which engage in lethal combat over female sexuals within their natal nests. Single queening, queen polyphenism, the loss of winged males and tolerance among wingless males appear to be derived traits that evolved with changes in nesting habits, colony size and the spread from tropical to seasonal environments. The aim of this review is to bring together the information on life-history evolution in Cardiocondyla and to highlight the suitability of this genus for functional genomic studies of adaptation, phenotypic plasticity, senescence, invasiveness and other key life-history traits of ants.
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Affiliation(s)
- Jürgen Heinze
- Zoologie/Evolutionsbiologie, Universität Regensburg, 93040 Regensburg, Germany
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14
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Jacobs S, Heinze J. Between fighting and tolerance: reproductive biology of wingless males in the ant Cardiocondyla venustula. INSECT SCIENCE 2017; 24:818-828. [PMID: 27188924 DOI: 10.1111/1744-7917.12359] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 03/23/2016] [Accepted: 04/27/2016] [Indexed: 06/05/2023]
Abstract
Male reproductive tactics vary widely across the species of the ant genus Cardiocondyla, from obligatory lethal combat among co-occurring males to complete mutual tolerance. The African species C. venustula Wheeler, 1908 has an intermediate phylogenetic position between taxa with fighting males and taxa with tolerant males and also shows an intermediate male behavior. Males from 2 native populations in South Africa and a population introduced to Puerto Rico attacked and killed freshly eclosing rivals but rarely engaged in deadly fights with adult competitors. Instead, several males per colony established small "territories" in their natal nests and defended them against other males. Males with a stable territory had more contact with female sexuals than nonterritorial males and more frequently engaged in mating attempts. In controlled choice experiments, female sexuals did not show any preference for particular males. We suggest that male territoriality in C. venustula is an adaptation to the seasonal production of large numbers of female sexuals by multiple mothers.
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Affiliation(s)
- Susanne Jacobs
- LS Zoologie/Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
| | - Jürgen Heinze
- LS Zoologie/Evolutionsbiologie, Universität Regensburg, Regensburg, Germany
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15
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Schrader L, Helanterä H, Oettler J. Accelerated Evolution of Developmentally Biased Genes in the Tetraphenic Ant Cardiocondyla obscurior. Mol Biol Evol 2017; 34:535-544. [PMID: 27999112 PMCID: PMC5400372 DOI: 10.1093/molbev/msw240] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Plastic gene expression underlies phenotypic plasticity and plastically expressed genes evolve under different selection regimes compared with ubiquitously expressed genes. Social insects are well-suited models to elucidate the evolutionary dynamics of plastic genes for their genetically and environmentally induced discrete polymorphisms. Here, we study the evolution of plastically expressed genes in the ant Cardiocondyla obscurior—a species that produces two discrete male morphs in addition to the typical female polymorphism of workers and queens. Based on individual-level gene expression data from 28 early third instar larvae, we test whether the same evolutionary dynamics that pertain to plastically expressed genes in adults also pertain to genes with plastic expression during development. In order to quantify plasticity of gene expression over multiple contrasts, we develop a novel geometric measure. For genes expressed during development, we show that plasticity of expression is positively correlated with evolutionary rates. We furthermore find a strong correlation between expression plasticity and expression variation within morphs, suggesting a close link between active and passive plasticity of gene expression. Our results support the notion of relaxed selection and neutral processes as important drivers in the evolution of adaptive plasticity.
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Affiliation(s)
- Lukas Schrader
- Institut für Zoologie, Universität Regensburg, Regensburg, Germany.,Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Heikki Helanterä
- Centre of Excellence in Biological Interactions, Department of Biosciences, University of Helsinki, Helsinki, Finland
| | - Jan Oettler
- Institut für Zoologie, Universität Regensburg, Regensburg, Germany
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16
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First come, first served: the first-emerging queen monopolizes reproduction in the ant Cardiocondyla “argyrotricha”. J ETHOL 2016. [DOI: 10.1007/s10164-016-0484-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Oettler J, Schrempf A. Fitness and aging in Cardiocondyla obscurior ant queens. CURRENT OPINION IN INSECT SCIENCE 2016; 16:58-63. [PMID: 27720051 DOI: 10.1016/j.cois.2016.05.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 05/02/2016] [Accepted: 05/11/2016] [Indexed: 06/06/2023]
Abstract
Easy maintenance, controlled mating and short generation time make Cardiocondyla obscurior an interesting model for social insect aging research. Using this ant we have begun to study the proximate genomic relationship between mating and aging. Although mating in general has a positive effect and results in fertile queens with long life but drastically reduced metabolic rates, mating can also dramatically reduce queen fitness. Here we review a decade of research on factors affecting queen aging rate and contrast these findings with studies on honeybees and solitary aging models. We conclude by giving a brief outlook of what is to be expected from this model in coming years.
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Affiliation(s)
- Jan Oettler
- Zoologie/Evolutionsbiologie, Universität Regensburg, D-93040 Regensburg, Germany.
| | - Alexandra Schrempf
- Zoologie/Evolutionsbiologie, Universität Regensburg, D-93040 Regensburg, Germany.
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A novel intracellular mutualistic bacterium in the invasive ant Cardiocondyla obscurior. ISME JOURNAL 2015; 10:376-88. [PMID: 26172209 DOI: 10.1038/ismej.2015.119] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 04/29/2015] [Accepted: 06/09/2015] [Indexed: 12/20/2022]
Abstract
The evolution of eukaryotic organisms is often strongly influenced by microbial symbionts that confer novel traits to their hosts. Here we describe the intracellular Enterobacteriaceae symbiont of the invasive ant Cardiocondyla obscurior, 'Candidatus Westeberhardia cardiocondylae'. Upon metamorphosis, Westeberhardia is found in gut-associated bacteriomes that deteriorate following eclosion. Only queens maintain Westeberhardia in the ovarian nurse cells from where the symbionts are transmitted to late-stage oocytes during nurse cell depletion. Functional analyses of the streamlined genome of Westeberhardia (533 kb, 23.41% GC content) indicate that neither vitamins nor essential amino acids are provided for the host. However, the genome encodes for an almost complete shikimate pathway leading to 4-hydroxyphenylpyruvate, which could be converted into tyrosine by the host. Taken together with increasing titers of Westeberhardia during pupal stage, this suggests a contribution of Westeberhardia to cuticle formation. Despite a widespread occurrence of Westeberhardia across host populations, one ant lineage was found to be naturally symbiont-free, pointing to the loss of an otherwise prevalent endosymbiont. This study yields insights into a novel intracellular mutualist that could play a role in the invasive success of C. obscurior.
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Schrader L, Simola DF, Heinze J, Oettler J. Sphingolipids, Transcription Factors, and Conserved Toolkit Genes: Developmental Plasticity in the Ant Cardiocondyla obscurior. Mol Biol Evol 2015; 32:1474-86. [PMID: 25725431 PMCID: PMC4615751 DOI: 10.1093/molbev/msv039] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Developmental plasticity allows for the remarkable morphological specialization of individuals into castes in eusocial species of Hymenoptera. Developmental trajectories that lead to alternative caste fates are typically determined by specific environmental stimuli that induce larvae to express and maintain distinct gene expression patterns. Although most eusocial species express two castes, queens and workers, the ant Cardiocondyla obscurior expresses diphenic females and males; this provides a unique system with four discrete phenotypes to study the genomic basis of developmental plasticity in ants. We sequenced and analyzed the transcriptomes of 28 individual C. obscurior larvae of known developmental trajectory, providing the first in-depth analysis of gene expression in eusocial insect larvae. Clustering and transcription factor binding site analyses revealed that different transcription factors and functionally distinct sets of genes are recruited during larval development to induce the four alternative trajectories. In particular, we found complex patterns of gene regulation pertaining to sphingolipid metabolism, a conserved molecular pathway involved in development, obesity, and aging.
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Affiliation(s)
- Lukas Schrader
- Department for Zoology/Evolutionary Biology, Institut für Zoologie, Universität Regensburg, Regensburg, Germany
| | - Daniel F Simola
- Department of Cell and Developmental Biology, University of Pennsylvania
| | - Jürgen Heinze
- Department for Zoology/Evolutionary Biology, Institut für Zoologie, Universität Regensburg, Regensburg, Germany
| | - Jan Oettler
- Department for Zoology/Evolutionary Biology, Institut für Zoologie, Universität Regensburg, Regensburg, Germany
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Bressan JMA, Benz M, Oettler J, Heinze J, Hartenstein V, Sprecher SG. A map of brain neuropils and fiber systems in the ant Cardiocondyla obscurior. Front Neuroanat 2015; 8:166. [PMID: 25698935 PMCID: PMC4316776 DOI: 10.3389/fnana.2014.00166] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 12/24/2014] [Indexed: 11/28/2022] Open
Abstract
A wide spectrum of occupied ecological niches and spectacular morphological adaptations make social insects a prime object for comparative neuroanatomical studies. Eusocial insects have evolved complex societies based on caste polyphenism. A diverse behavioral repertoire of morphologically distinct castes of the same species requires a high degree of plasticity in the central nervous system. We have analyzed the central brain neuropils and fiber tract systems of the worker of the ant Cardiocondylaobscurior, a model for the study of social traits. Our analysis is based on whole mount preparations of adult brains labeled with an antibody against Drosophila-Synapsin, which cross-reacts strongly with synapses in Cardiocondyla. Neuropil compartments stand out as domains with a certain texture and intensity of the anti-Synapsin signal. By contrast, fiber tracts, which are composed of bundles of axons accompanied by glia and are devoid of synapses, appear as channels or sheaths with low anti-Synapsin signal. We have generated a digital 3D atlas of the Cardiocondyla brain neuropil. The atlas provides a reference for future studies of brain polymorphisms in distinct castes, brain development or localization of neurotransmitter systems.
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Affiliation(s)
- Joris M A Bressan
- Department of Biology, Institute of Developmental and Cell Biology, University of Fribourg Fribourg, Switzerland
| | - Martin Benz
- Department of Biology, Institute of Developmental and Cell Biology, University of Fribourg Fribourg, Switzerland
| | - Jan Oettler
- Biologie I, Universität Regensburg Regensburg, Germany
| | - Jürgen Heinze
- Biologie I, Universität Regensburg Regensburg, Germany
| | - Volker Hartenstein
- Department of Molecular, Cell and Developmental Biology, University of California Los Angeles, CA, USA
| | - Simon G Sprecher
- Department of Biology, Institute of Developmental and Cell Biology, University of Fribourg Fribourg, Switzerland
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The Caucaso-Anatolian slave-making ant Myrmoxenus tamarae (Arnoldi, 1968) and its more widely distributed congener Myrmoxenus ravouxi (André, 1896): a multidisciplinary comparison (Hymenoptera: Formicidae). ORG DIVERS EVOL 2014. [DOI: 10.1007/s13127-014-0174-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Heinze J, Frohschammer S, Bernadou A. Queen life-span and total reproductive success are positively associated in the ant Cardiocondyla cf. kagutsuchi. Behav Ecol Sociobiol 2013. [DOI: 10.1007/s00265-013-1567-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Morris MR, Goedert D, Abbott JK, Robinson DM, Rios-Cardenas O. Intralocus Tactical Conflict and the Evolution of Alternative Reproductive Tactics. ADVANCES IN THE STUDY OF BEHAVIOR 2013. [DOI: 10.1016/b978-0-12-407186-5.00007-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Cruaud A, Jabbour-Zahab R, Genson G, Kjellberg F, Kobmoo N, van Noort S, Da-Rong Y, Yan-Qiong P, Ubaidillah R, Hanson PE, Santos-Mattos O, Farache FHA, Pereira RAS, Kerdelhué C, Rasplus JY. Phylogeny and evolution of life-history strategies in the Sycophaginae non-pollinating fig wasps (Hymenoptera, Chalcidoidea). BMC Evol Biol 2011; 11:178. [PMID: 21696591 PMCID: PMC3145598 DOI: 10.1186/1471-2148-11-178] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 06/22/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Non-pollinating Sycophaginae (Hymenoptera, Chalcidoidea) form small communities within Urostigma and Sycomorus fig trees. The species show differences in galling habits and exhibit apterous, winged or dimorphic males. The large gall inducers oviposit early in syconium development and lay few eggs; the small gall inducers lay more eggs soon after pollination; the ostiolar gall-inducers enter the syconium to oviposit and the cleptoparasites oviposit in galls induced by other fig wasps. The systematics of the group remains unclear and only one phylogeny based on limited sampling has been published to date. Here we present an expanded phylogeny for sycophagine fig wasps including about 1.5 times the number of described species. We sequenced mitochondrial and nuclear markers (4.2 kb) on 73 species and 145 individuals and conducted maximum likelihood and Bayesian phylogenetic analyses. We then used this phylogeny to reconstruct the evolution of Sycophaginae life-history strategies and test if the presence of winged males and small brood size may be correlated. RESULTS The resulting trees are well resolved and strongly supported. With the exception of Apocrytophagus, which is paraphyletic with respect to Sycophaga, all genera are monophyletic. The Sycophaginae are divided into three clades: (i) Eukoebelea; (ii) Pseudidarnes, Anidarnes and Conidarnes and (iii) Apocryptophagus, Sycophaga and Idarnes. The ancestral states for galling habits and male morphology remain ambiguous and our reconstructions show that the two traits are evolutionary labile. CONCLUSIONS The three main clades could be considered as tribes and we list some morphological characters that define them. The same biologies re-evolved several times independently, which make Sycophaginae an interesting model to test predictions on what factors will canalize the evolution of a particular biology. The ostiolar gall-inducers are the only monophyletic group. In 15 Myr, they evolved several morphological adaptations to enter the syconia that make them strongly divergent from their sister taxa. Sycophaginae appears to be another example where sexual selection on male mating opportunities favored winged males in species with small broods and wingless males in species with large broods. However, some species are exceptional in that they lay few eggs but exhibit apterous males, which we hypothesize could be due to other selective pressures selecting against the re-appearance of winged morphs.
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Affiliation(s)
- Astrid Cruaud
- INRA-UMR Centre de Biologie et de Gestion des Populations, CBGP, (INRA/IRD/CIRAD/Montpellier SupAgro), Campus international de Baillarguet, CS 30016, 34988 Montferrier-sur Lez, France
| | - Roula Jabbour-Zahab
- INRA-UMR Centre de Biologie et de Gestion des Populations, CBGP, (INRA/IRD/CIRAD/Montpellier SupAgro), Campus international de Baillarguet, CS 30016, 34988 Montferrier-sur Lez, France
| | - Gwenaëlle Genson
- INRA-UMR Centre de Biologie et de Gestion des Populations, CBGP, (INRA/IRD/CIRAD/Montpellier SupAgro), Campus international de Baillarguet, CS 30016, 34988 Montferrier-sur Lez, France
| | - Finn Kjellberg
- CNRS-UMR Centre d'Ecologie Fonctionnelle et Evolutive, CEFE, 1919 route de Mende, 34293 Montpellier Cedex 5, France
| | - Noppol Kobmoo
- CNRS-UMR Centre d'Ecologie Fonctionnelle et Evolutive, CEFE, 1919 route de Mende, 34293 Montpellier Cedex 5, France
| | - Simon van Noort
- Natural History Division, South African Museum, Iziko Museums of Cape Town, PO Box 61, Cape Town 8000, South Africa
| | - Yang Da-Rong
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, 88 Xuefu Road, 650223 Kunming, Yunnan, China
| | - Peng Yan-Qiong
- Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, 88 Xuefu Road, 650223 Kunming, Yunnan, China
| | - Rosichon Ubaidillah
- Entomology Laboratory, Zoology Division (Museum Zoologicum Bogoriense). Center Research for Biology, LIPI, Gedung Widyasatwaloka Jl. Raya Jakarta-Bogor, Km 46, Cobinong 16911, Bogor, Indonesia
| | - Paul E Hanson
- Escuela de Biología. Universidad de Costa Rica. A.P. 2060 San Pedro de Montes de Oca. San José, Costa Rica
| | - Otilene Santos-Mattos
- Instituto Nacional de Pesquisa da Amazônia, av Andre Araujo 2936, 69060-001, Manaus, Amazonas, Brazil
| | - Fernando HA Farache
- Depto de Biologia/FFCLRP-USP, Av. Bandeirantes, 3900, 14040-901 - Ribeirão Preto, SP, Brazil
| | - Rodrigo AS Pereira
- Depto de Biologia/FFCLRP-USP, Av. Bandeirantes, 3900, 14040-901 - Ribeirão Preto, SP, Brazil
| | - Carole Kerdelhué
- INRA-UMR Centre de Biologie et de Gestion des Populations, CBGP, (INRA/IRD/CIRAD/Montpellier SupAgro), Campus international de Baillarguet, CS 30016, 34988 Montferrier-sur Lez, France
| | - Jean-Yves Rasplus
- INRA-UMR Centre de Biologie et de Gestion des Populations, CBGP, (INRA/IRD/CIRAD/Montpellier SupAgro), Campus international de Baillarguet, CS 30016, 34988 Montferrier-sur Lez, France
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