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Li CY, Bowers JM, Alexander TA, Behrens KA, Jackson P, Amini CJ, Juntti SA. A pheromone receptor in cichlid fish mediates attraction to females but inhibits male parental care. Curr Biol 2024; 34:3866-3880.e7. [PMID: 39094572 PMCID: PMC11387146 DOI: 10.1016/j.cub.2024.07.029] [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: 03/08/2024] [Revised: 05/24/2024] [Accepted: 07/03/2024] [Indexed: 08/04/2024]
Abstract
Reproductive behaviors differ across species, but the mechanisms that control variation in mating and parental care systems remain unclear. In many animal species, pheromones guide mating and parental care. However, it is not well understood how vertebrate pheromone signaling evolution can lead to new reproductive behavior strategies. In fishes, prostaglandin F2α (PGF2α) drives mating and reproductive pheromone signaling in fertile females, but this pheromonal activity appears restricted to specific lineages, and it remains unknown how a female fertility pheromone is sensed for most fish species. Here, we utilize single-cell transcriptomics and CRISPR gene editing in a cichlid fish model to identify and test the roles of key genes involved in olfactory sensing of reproductive cues. We find that a pheromone receptor, Or113a, detects fertile cichlid females and thereby promotes male attraction and mating behavior, sensing a ligand other than PGF2α. Furthermore, while cichlid fishes exhibit extensive parental care, for most species, care is provided solely by females. We find that males initiate mouthbrooding parental care if they have disrupted signaling in ciliated sensory neurons due to cnga2b mutation or if or113a is inactivated. Together, these results show that distinct mechanisms of pheromonal signaling drive reproductive behaviors across taxa. Additionally, these findings indicate that a single pheromone receptor has gained a novel role in behavior regulation, driving avoidance of paternal care among haplochromine cichlid fishes. Lastly, a sexually dimorphic, evolutionarily derived parental behavior is controlled by central circuits present in both sexes, while olfactory signals gate this behavior in a sex-specific manner.
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Affiliation(s)
- Cheng-Yu Li
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Jessica M Bowers
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | | | - Kristen A Behrens
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Peter Jackson
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Cyrus J Amini
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Scott A Juntti
- Department of Biology, University of Maryland, College Park, MD 20742, USA.
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2
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Maruska KP, Anselmo CM, King T, Mobley RB, Ray EJ, Wayne R. Endocrine and neuroendocrine regulation of social status in cichlid fishes. Horm Behav 2022; 139:105110. [PMID: 35065406 DOI: 10.1016/j.yhbeh.2022.105110] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 12/28/2021] [Accepted: 01/04/2022] [Indexed: 01/07/2023]
Abstract
Position in a dominance hierarchy profoundly impacts group members' survival, health, and reproductive success. Thus, understanding the mechanisms that regulate or are associated with an individuals' social position is important. Across taxa, various endocrine and neuroendocrine signaling systems are implicated in the control of social rank. Cichlid fishes, with their often-limited resources of food, shelter, and mates that leads to competition, have provided important insights on the proximate and ultimate mechanisms related to establishment and maintenance of dominance hierarchies. Here we review the existing information on the relationships between endocrine (e.g., circulating hormones, gonadal and other tissue measures) and neuroendocrine (e.g., central neuropeptides, biogenic amines, steroids) systems and dominant and subordinate social rank in male cichlids. Much of the current literature is focused on only a few representative cichlids, particularly the African Astatotilapia burtoni, and several other African and Neotropical species. Many hormonal regulators show distinct differences at multiple biological levels between dominant and subordinate males, but generalizations are complicated by variations in experimental paradigms, methodological approaches, and in the reproductive and parental care strategies of the study species. Future studies that capitalize on the diversity of hierarchical structures among cichlids should provide insights towards better understanding the endocrine and neuroendocrine mechanisms contributing to social rank. Further, examination of this topic in cichlids will help reveal the selective pressures driving the evolution of endocrine-related phenotypic traits that may facilitate an individual's ability to acquire and maintain a specific social rank to improve survival and reproductive success.
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Affiliation(s)
- Karen P Maruska
- Department of Biological Sciences, 202 Life Sciences Bldg., Louisiana State University, Baton Rouge, LA 70803, United States of America.
| | - Chase M Anselmo
- Department of Biological Sciences, 202 Life Sciences Bldg., Louisiana State University, Baton Rouge, LA 70803, United States of America
| | - Teisha King
- Department of Biological Sciences, 202 Life Sciences Bldg., Louisiana State University, Baton Rouge, LA 70803, United States of America
| | - Robert B Mobley
- Department of Biological Sciences, 202 Life Sciences Bldg., Louisiana State University, Baton Rouge, LA 70803, United States of America
| | - Emily J Ray
- Department of Biological Sciences, 202 Life Sciences Bldg., Louisiana State University, Baton Rouge, LA 70803, United States of America
| | - Rose Wayne
- Department of Biological Sciences, 202 Life Sciences Bldg., Louisiana State University, Baton Rouge, LA 70803, United States of America
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3
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Diaz-Verdugo C, Sun GJ, Fawcett CH, Zhu P, Fishman MC. Mating Suppresses Alarm Response in Zebrafish. Curr Biol 2019; 29:2541-2546.e3. [PMID: 31327717 DOI: 10.1016/j.cub.2019.06.047] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 05/13/2019] [Accepted: 06/17/2019] [Indexed: 10/26/2022]
Abstract
Mating and flight from threats are innate behaviors that enhance species survival [1, 2]. Stimuli to these behaviors often are contemporaneous and conflicting [3, 4]. Both how such conflicts are resolved and where in the brain such decisions are made are poorly understood. For teleosts, olfactory stimuli are key elements of mating and threat responses [5-7]. For example, zebrafish manifest a stereotypical escape response when exposed to an alarm substance released from injured conspecific skin ("skin extract") [8, 9]. We find that when mating, fish ignore this threatening stimulus. Water conditioned by the mating fish ("mating water") suffices to suppress much of the alarm-response behavior. By 2-photon imaging of calcium transients [10], we mapped the regions of the brain responding to skin extract and to mating water. In the telencephalon, we found regions where the responses overlap, one region (medial Dp) to be predominantly activated by skin extract, and another, Vs, to be predominantly activated by mating water. When mating water and skin extract were applied simultaneously, the alarm-specific response was suppressed, while the mating-water-specific response was retained, corresponding to the dominance of mating over flight behavior. The choice made, for reproduction over escape, is opposite to that of mammals, presumably reflecting how the balance affects species survival.
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Affiliation(s)
- Carmen Diaz-Verdugo
- Novartis Institutes for Biomedical Research, Chemical Biology & Therapeutics, 181 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Gerald J Sun
- Novartis Institutes for Biomedical Research, Chemical Biology & Therapeutics, 181 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Caroline H Fawcett
- Novartis Institutes for Biomedical Research, Chemical Biology & Therapeutics, 181 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Peixin Zhu
- Novartis Institutes for Biomedical Research, Chemical Biology & Therapeutics, 181 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Mark C Fishman
- Harvard University, Department of Stem Cell and Regenerative Biology, 7 Divinity Avenue, Cambridge, MA 02138, USA.
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4
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Abstract
The tremendous diversity of animal behaviors has inspired generations of scientists from an array of biological disciplines. To complement investigations of ecological and evolutionary factors contributing to behavioral evolution, modern sequencing, gene editing, computational and neuroscience tools now provide a means to discover the proximate mechanisms upon which natural selection acts to generate behavioral diversity. Social behaviors are motivated behaviors that can differ tremendously between closely related species, suggesting phylogenetic plasticity in their underlying biological mechanisms. In addition, convergent evolution has repeatedly given rise to similar forms of social behavior and mating systems in distantly related species. Social behavioral divergence and convergence provides an entry point for understanding the neurogenetic mechanisms contributing to behavioral diversity. We argue that the greatest strides in discovering mechanisms contributing to social behavioral diversity will be achieved through integration of interdisciplinary comparative approaches with modern tools in diverse species systems. We review recent advances and future potential for discovering mechanisms underlying social behavioral variation; highlighting patterns of social behavioral evolution, oxytocin and vasopressin neuropeptide systems, genetic/transcriptional "toolkits," modern experimental tools, and alternative species systems, with particular emphasis on Microtine rodents and Lake Malawi cichlid fishes.
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Affiliation(s)
- Zachary V Johnson
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Larry J Young
- Center for Translational Social Neuroscience, Silvio O. Conte Center for Oxytocin and Social Cognition, Department of Psychiatry and Behavioral Sciences, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA
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5
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Rahmouni C, Vanhove MPM, Šimková A. Seven new species of Cichlidogyrus Paperna, 1960 (Monogenea: Dactylogyridae) parasitizing the gills of Congolese cichlids from northern Lake Tanganyika. PeerJ 2018; 6:e5604. [PMID: 30370182 PMCID: PMC6202960 DOI: 10.7717/peerj.5604] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 08/16/2018] [Indexed: 12/30/2022] Open
Abstract
Seven new species of Cichlidogyrus Paperna, 1960 (Monogenea: Dactylogyridae) isolated from the gills of six cichlid host species belonging to four tribes and sampled from the Congolese coastline of Lake Tanganyika (LT) are described: Cichlidogyrus adkoningsi sp. nov. from Cyphotilapia frontosa (tribe Cyphotilapiini); C. koblmuelleri sp. nov. from Cardiopharynx schoutedeni (Ectodini); C. habluetzeli sp. nov. from C. schoutedeni and C. frontosa; C. antoineparisellei sp. nov. from Interochromis loocki (Tropheini); C. masilyai sp. nov. from Petrochromis orthognathus (Tropheini); C. salzburgeri sp. nov. from P. trewavasae, and C. sergemorandi sp. nov. from Tylochromis polylepis (Tylochromini). This study represents the first parasitological examination of cyphotilapiine cichlid hosts. Representatives of the Tanganyikan ectodine, tropheine, and tylochromine cichlids previously sampled from various localities in the lake yielded nine, twelve, and two described species of Cichlidogyrus, respectively. The study further includes a morphological characterization of the male copulatory organ of six undescribed species of Cichlidogyrus found on the gills of the tropheines I. loocki and P. orthognathus, and on those of Callochromis melanostigma and Xenotilapia flavipinnis (both Ectodini). Geographical variation in the monogenean fauna of I. loocki was observed. The most closely related cichlid species investigated in this study harboured Cichlidogyrus spp. exhibiting some similarities in their sclerotized structures. Thus, our paper provides additional evidence of the high species richness of Cichlidogyrus and the link with their hosts’s phylogenetic affinities in LT.
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Affiliation(s)
- Chahrazed Rahmouni
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Maarten P M Vanhove
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic.,Zoology Unit, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland.,Laboratory of Biodiversity and Evolutionary Genomics, Department of Biology, University of Leuven, Leuven, Belgium.,Centre for Environmental Sciences, Research Group Zoology: Biodiversity and Toxicology, Universiteit Hasselt, Diepenbeek, Belgium
| | - Andrea Šimková
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
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6
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Renn SC, Machado HE, Duftner N, Sessa AK, Harris RM, Hofmann HA. Gene expression signatures of mating system evolution. Genome 2018; 61:287-297. [DOI: 10.1139/gen-2017-0075] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The diversity of mating systems among animals is astounding. Importantly, similar mating systems have evolved even across distantly related taxa. However, our understanding of the mechanisms underlying these convergently evolved phenotypes is limited. Here, we examine on a genomic scale the neuromolecular basis of social organization in cichlids of the tribe Ectodini from Lake Tanganyika. Using field-collected males and females of four closely related species representing two independent evolutionary transitions from polygyny to monogamy, we take a comparative transcriptomic approach to test the hypothesis that these independent transitions have recruited similar gene sets. Our results demonstrate that while lineage and species exert a strong influence on neural gene expression profiles, social phenotype can also drive gene expression evolution. Specifically, 331 genes (∼6% of those assayed) were associated with monogamous mating systems independent of species or sex. Among these genes, we find a strong bias (4:1 ratio) toward genes with increased expression in monogamous individuals. A highly conserved nonapeptide system known to be involved in the regulation of social behavior across animals was not associated with mating system in our analysis. Overall, our findings suggest deep molecular homologies underlying the convergent or parallel evolution of monogamy in different cichlid lineages of Ectodini.
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Affiliation(s)
| | - Heather E. Machado
- Department of Biology, Reed College
- Department of Biology, Stanford University
| | - Nina Duftner
- Department of Integrative Biology, the University of Texas at Austin
| | - Anna K. Sessa
- Department of Integrative Biology, the University of Texas at Austin
| | - Rayna M. Harris
- Department of Integrative Biology, the University of Texas at Austin
- Institute for Cellular and Molecular Biology, the University of Texas at Austin
| | - Hans A. Hofmann
- Department of Integrative Biology, the University of Texas at Austin
- Institute for Cellular and Molecular Biology, the University of Texas at Austin
- Center for Computational Biology and Bioinformatics, Institute for Neuroscience, the University of Texas at Austin
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7
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Evolution of opercle shape in cichlid fishes from Lake Tanganyika - adaptive trait interactions in extant and extinct species flocks. Sci Rep 2015; 5:16909. [PMID: 26584885 PMCID: PMC4653715 DOI: 10.1038/srep16909] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 10/22/2015] [Indexed: 11/08/2022] Open
Abstract
Phenotype-environment correlations and the evolution of trait interactions in adaptive radiations have been widely studied to gain insight into the dynamics underpinning rapid species diversification. In this study we explore the phenotype-environment correlation and evolution of operculum shape in cichlid fishes using an outline-based geometric morphometric approach combined with stable isotope indicators of macrohabitat and trophic niche. We then apply our method to a sample of extinct saurichthyid fishes, a highly diverse and near globally distributed group of actinopterygians occurring throughout the Triassic, to assess the utility of extant data to inform our understanding of ecomorphological evolution in extinct species flocks. A series of comparative methods were used to analyze shape data for 54 extant species of cichlids (N = 416), and 6 extinct species of saurichthyids (N = 44). Results provide evidence for a relationship between operculum shape and feeding ecology, a concentration in shape evolution towards present along with evidence for convergence in form, and significant correlation between the major axes of shape change and measures of gut length and body elongation. The operculum is one of few features that can be compared in extant and extinct groups, enabling reconstruction of phenotype-environment interactions and modes of evolutionary diversification in deep time.
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8
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Schneider K, Koblmüller S, Sefc KM. HEXT, a software supporting tree-based screens for hybrid taxa in multilocus data sets, and an evaluation of the homoplasy excess test. Methods Ecol Evol 2015; 7:358-368. [PMID: 27066216 PMCID: PMC4824276 DOI: 10.1111/2041-210x.12490] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 08/27/2015] [Indexed: 12/01/2022]
Abstract
The homoplasy excess test (HET) is a tree-based screen for hybrid taxa in multilocus nuclear phylogenies. Homoplasy between a hybrid taxon and the clades containing the parental taxa reduces bootstrap support in the tree. The HET is based on the expectation that excluding the hybrid taxon from the data set increases the bootstrap support for the parental clades, whereas excluding non-hybrid taxa has little effect on statistical node support. To carry out a HET, bootstrap trees are calculated with taxon-jackknife data sets, that is excluding one taxon (species, population) at a time. Excess increase in bootstrap support for certain nodes upon exclusion of a particular taxon indicates the hybrid (the excluded taxon) and its parents (the clades with increased support).We introduce a new software program, hext, which generates the taxon-jackknife data sets, runs the bootstrap tree calculations, and identifies excess bootstrap increases as outlier values in boxplot graphs. hext is written in r language and accepts binary data (0/1; e.g. AFLP) as well as co-dominant SNP and genotype data.We demonstrate the usefulness of hext in large SNP data sets containing putative hybrids and their parents. For instance, using published data of the genus Vitis (~6,000 SNP loci), hext output supports V. × champinii as a hybrid between V. rupestris and V. mustangensis.With simulated SNP and AFLP data sets, excess increases in bootstrap support were not always connected with the hybrid taxon (false positives), whereas the expected bootstrap signal failed to appear on several occasions (false negatives). Potential causes for both types of spurious results are discussed.With both empirical and simulated data sets, the taxon-jackknife output generated by hext provided additional signatures of hybrid taxa, including changes in tree topology across trees, consistent effects of exclusions of the hybrid and the parent taxa, and moderate (rather than excessive) increases in bootstrap support. hext significantly facilitates the taxon-jackknife approach to hybrid taxon detection, even though the simple test for excess bootstrap increase may not reliably identify hybrid taxa in all applications.
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Affiliation(s)
- Kevin Schneider
- Institute of Zoology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria ; Department of Systematic Botany and Geobotany, Institute of Plant Sciences, University of Graz, Holteigasse 6, 8010 Graz, Austria
| | - Stephan Koblmüller
- Institute of Zoology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Kristina M Sefc
- Institute of Zoology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
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9
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Muschick M, Nosil P, Roesti M, Dittmann MT, Harmon L, Salzburger W. Testing the stages model in the adaptive radiation of cichlid fishes in East African Lake Tanganyika. Proc Biol Sci 2015; 281:rspb.2014.0605. [PMID: 25274371 DOI: 10.1098/rspb.2014.0605] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Adaptive radiation (AR) is a key process in the origin of organismal diversity. However, the evolution of trait disparity in connection with ecological specialization is still poorly understood. Available models for vertebrate ARs predict that diversification occurs in the form of temporal stages driven by different selective forces. Here, we investigate the AR of cichlid fishes in East African Lake Tanganyika and use macroevolutionary model fitting to evaluate whether diversification happened in temporal stages. Six trait complexes, for which we also provide evidence of their adaptiveness, are analysed with comparative methods: body shape, pharyngeal jaw shape, gill raker traits, gut length, brain weight and body coloration. Overall, we do not find strong evidence for the 'stages model' of AR. However, our results suggest that trophic traits diversify earlier than traits implicated in macrohabitat adaptation and that sexual communication traits (i.e. coloration) diversify late in the radiation.
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Affiliation(s)
- Moritz Muschick
- Zoological Institute, University of Basel, Basel 4051, Switzerland Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Patrik Nosil
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Marius Roesti
- Zoological Institute, University of Basel, Basel 4051, Switzerland
| | - Marie Theres Dittmann
- Institute of Agricultural Sciences, ETH Zurich, Zürich 8092, Switzerland Clinic for Zoo Animals, Wildlife and Exotic Pets, Vetsuisse Faculty, University of Zurich, Zürich 8057, Switzerland
| | - Luke Harmon
- Department of Biological Sciences and Institute for Bioinformatics and Evolutionary Studies (IBEST), University of Idaho, Moscow, ID, USA
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10
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Maruska KP. Social regulation of reproduction in male cichlid fishes. Gen Comp Endocrinol 2014; 207:2-12. [PMID: 24859257 DOI: 10.1016/j.ygcen.2014.04.038] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Revised: 04/25/2014] [Accepted: 04/30/2014] [Indexed: 11/19/2022]
Abstract
Social interactions and relative positions within a dominance hierarchy have helped shape the evolution of reproduction in many animals. Since reproduction is crucial in all animals, and rank typically regulates access to reproductive opportunities, understanding the mechanisms that regulate socially-induced reproductive processes is extremely important. How does position in a dominance hierarchy impact an individual's reproductive behavior, morphology, and physiology? Teleost fishes, and cichlids in particular, are ideally-suited models for studying how social status influences reproduction on multiple levels of biological organization. Here I review the current knowledge on the reproductive behavioral and physiological consequences of relative position in a dominance hierarchy, with a particular focus on male cichlids. Dominant and subordinate social status is typically associated with distinct differences in activity along the entire hypothalamic-pituitary-gonadal axis. Further, when transitions in social status occur between subordinate and dominant individuals, there are plastic changes from whole-organism behavior to molecular-level gene expression modifications that occur quickly. These rapid changes in behavior and physiology have allowed cichlids the flexibility to adapt to and thrive in their often dynamic physical and social environments. Studies in cichlid fishes have, and will continue, to advance our understanding of how the social environment can modulate molecular, cellular, and behavioral outcomes relevant to reproductive success. Future studies that take advantage of the extreme diversity in mating systems, reproductive tactics, and parental care strategies within the cichlid group will help generate hypotheses and careful experimental tests on the mechanisms governing the social control of reproduction in many vertebrates.
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Affiliation(s)
- Karen P Maruska
- Department of Biological Sciences, 202 Life Sciences Bldg., Louisiana State University, Baton Rouge, LA 70803, United States.
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11
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Affiliation(s)
- M Emília Santos
- Zoological Institute, University of Basel, Vesalgasse 1, CH-4051 Basel, Switzerland.
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12
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Sefc KM. Mating and Parental Care in Lake Tanganyika's Cichlids. INTERNATIONAL JOURNAL OF EVOLUTIONARY BIOLOGY 2011; 2011:470875. [PMID: 21822482 PMCID: PMC3142683 DOI: 10.4061/2011/470875] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 03/22/2011] [Accepted: 05/02/2011] [Indexed: 11/20/2022]
Abstract
Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and piracy. Moreover, reproductive behaviors sometimes vary within species both in space and in time. Here, I survey reports on mating and parenting behaviors of Lake Tanganyika cichlid species and address the evolution of mating and parental care patterns and sexual dimorphism. Notes on measures of sexual selection intensity and the difficulties of defining mating systems and estimating selection intensities at species level conclude the essay.
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Affiliation(s)
- Kristina M. Sefc
- Department of Zoology, Karl-Franzens University Graz, Universitätsplatz 2, 8010 Graz, Austria
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