DOCSLIB.ORG

Ramallo, Martín Roberto. 2016 12 02

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ramallo, Martín Roberto. 2016 12 02 Tesis Doctoral Aromatasa cerebral (Cyp19a1b): caracterización y relación con el comportamiento agonístico y el período de cuidado parental en el pez cíclido Cichlasoma dimerus Ramallo, Martín Roberto 2016-12-02 Este documento forma parte de la colección de tesis doctorales y de maestría de la Biblioteca Central Dr. Luis Federico Leloir, disponible en digital.bl.fcen.uba.ar. Su utilización debe ser acompañada por la cita bibliográfica con reconocimiento de la fuente. This document is part of the doctoral theses collection of the Central Library Dr. Luis Federico Leloir, available in digital.bl.fcen.uba.ar. It should be used accompanied by the corresponding citation acknowledging the source. Cita tipo APA: Ramallo, Martín Roberto. (2016-12-02). Aromatasa cerebral (Cyp19a1b): caracterización y relación con el comportamiento agonístico y el período de cuidado parental en el pez cíclido Cichlasoma dimerus. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Cita tipo Chicago: Ramallo, Martín Roberto. "Aromatasa cerebral (Cyp19a1b): caracterización y relación con el comportamiento agonístico y el período de cuidado parental en el pez cíclido Cichlasoma dimerus". Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. 2016-12-02. Dirección: Biblioteca Central Dr. Luis F. Leloir, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Contacto: [email protected] Intendente Güiraldes 2160 - C1428EGA - Tel. (++54 +11) 4789-9293 UNIVERSIDAD DE BUENOS AIRES Facultad de Ciencias Exactas y Naturales Departamento de Biodiversidad y Biología Experimental Aromatasa cerebral (Cyp19a1b): caracterización y relación con el comportamiento agonístico y el período de cuidado parental en el pez cíclido Cichlasoma dimerus Tesis presentada para optar al título de Doctor de la Universidad de Buenos Aires en el área de Ciencias Biológicas Martín Roberto Ramallo Directores de tesis: Dr. Matías Pandolfi Dr. Gustavo M. Somoza Consejero de Estudios: Dra. Paula Vissio Lugar de trabajo: Laboratorio de Neuroendocrinología y Comportamiento. DBBE, UBA e IBBEA, CONICET, Facultad de Ciencias Exactas y Naturales, UBA. Ciudad Autónoma de Buenos Aires, 2016 Aromatasa cerebral (Cyp19a1b): caracterización y relación con el comportamiento agonístico y el período de cuidado parental en el pez cíclido Cichlasoma dimerus. En todos los vertebrados, la enzima citocromo P450 aromatasa, es la responsable de la síntesis de estrógenos a partir de andrógenos. En ciertas áreas específicas del cerebro de los peces teleósteos la producción de estrógenos cerebrales es entre 100 y 1000 veces mayor comparada con las regiones homólogas del cerebro de otros grupos de vertebrados. La base de tales niveles radica en parte a la expresión de una variante de la enzima aromatasa, conocida como aromatasa cerebral, producto de uno de los dos genes parálogos que codifican para aromatasas (cerebral y gonadal) en teleósteos. Ya que la distribución neuroanatómica de las células productoras de aromatasa cerebral coincide parcialmente con áreas del cerebro involucradas en la regulación de comportamientos sociales, decidimos analizar el papel de la misma en la regulación del comportamiento agonístico y del cuidado maternal, en la chanchita Cichlasoma dimerus. Por medio de un protocolo de inmunohitoquímica se detectó la presencia de esta enzima en el cerebro anterior de la chanchita, en áreas involucradas en la regulación de comportamientos sociales. Luego, se caracterizaron la fisiología y el comportamiento de machos de chanchita de distinto estatus social (dominante vs. subordinado), y su relación con la expresión de aromatasa cerebral en el cerebro y la hipófisis. Los machos dominantes presentaron niveles mayores de andrógenos circulantes, mientras que los machos subordinados se caracterizaron por poseer nieles ás altos de 7β-estradiol, y una tasa espermatogénica relativamente menor. Si bien no se observó un efecto del estatus social sobre la expresión de la enzima, los niveles de expresión de la misma en hipófisis correlacionaron con la frecuencia de comportamientos agonísticos, sugiriendo un papel novedoso de la hipófisis en la regulación del comportamiento social a través de la síntesis de estrógenos. En las hembras se analizaron los perfiles de expresión de ambas variantes de la enzima aromatasa (cerebral y gonadal) a lo largo del período de cuidado parental, y su relación con parámetros fisiológicos y reproductivos. El inicio del cuidado maternal resultó en una caída específica de la síntesis de esteroides sexuales y de la tasa de maduración ovárica, mientras que los niveles de expresión de ambas aromatasas resultaron independientes de la presencia de la progenie. Por lo tanto, el estatus social en los machos y el cuidado parental en las hembras, repercuten fuertemente sobre los niveles de esteroides sexuales y el estado de las gónadas, o viceversa, sin que resulte afectada la expresión de aromatasa en cerebro anterior e hipófisis. Palabras claves: aromatasa cerebral, aromatasa gonadal, esteroides sexuales, cíclidos, comportamiento agonístico, cuidado maternal, Cichlasoma dimerus. Brain aromatase (Cyp19a1b): characterization and its relationship with agonistic behavior and parental care in the cichlid fish Cichlasoma dimerus In all vertebrates, the enzyme aromatase cytochrome P450, is responsible for estrogen synthesis by aromatization of androgens. Estrogen synthesis within particular brain regions of the teleost brain is between 100 and 1000 times higher than that observed in the homologues brain areas of other vertebrates. The basis of such high levels lies in part due to the expression of a variant of the enzyme aromatase, known as brain aromatase, which is the product of one of two paralogous genes encoding aromatase enzymes (brain and gonadal aromatase) in teleosts. The neuroanatomical distribution of brain aromatase overlaps with brain areas involved in the regulation of social behavior. Thus, the objective of this thesis was to analyze the role of brain aromatase in the regulation of agonistic behavior and maternal care in Cichlasoma dimerus, locally known as chanchita. Through an immunohistochemical study, the presence of the enzyme was detected in forebrain regions, in areas involved in the regulation of social behaviors. Then, the physiology and behavior of male chanchitas of different social status (dominant vs. subordinate) were characterized, and their relationship with the expression of brain aromatase in the brain and pituitary was assessed. Dominant males had higher circulating androgen levels, while subordinate males were characterized by a higher 7β-estradiol plasma concentration, and a relatively lower spermatogenic rate. While the social status ha no effect on the expression of forebrain and pituitary brain aromatase, the expression levels at pituitary correlated with the frequency of agonistic behaviors, suggesting a novel role of the pituitary gland in the regulation of social behavior through estrogen synthesis. In female chanchitas, the expression profiles of both aromatase gene variants (brain and gonadal) were examined throughout the parental care period, and their relation to physiological and reproductive parameters were analyzed. The onset of maternal care resulted in a specific downregulation in sex steroid synthesis and ovarian maturation rate, while levels of expression of both aromatases were independent of the presence of the progeny. Therefore, the social status in males and parental care in females of the cichlid chanchita, have a strong effect on sex steroids levels and gonadal state, or vice versa, though aromatase expression in whole forebrain and pituitary samples was unaffected. Keywords: brain aromatase, gonadal aromatase, sex steroids, cichlids, agonistic behavior, maternal care, Cichlasoma dimerus. Agradecimientos La emergencia o el surgimiento hacen referencia a aquellas propiedades o procesos de un sistema no reducibles a las propiedades o procesos de sus partes constituyentes. El todo es más que la suma de las partes, así como este trabajo de tesis es en parte de todos. Primero quiero agradecer a la Facultad de Ciencias Exactas y Naturales de la Universidad de Buenos Aires por brindarme a mí y a muchos otros, la oportunidad de recibir una educación de calidad y desarrollarnos como profesionales. A los profesores de la carrera que se esforzaron para que las clases sean mucho más que el simple contenido de un libro académico. A mis directores Matías Pandolfi y Gustavo Somoza. A Matías, gracias por haberme re-elegido para formar parte de tu equipo de trabajo durante 8 años! Por darme innumerables oportunidades y confiar más en mí de lo que yo confío en mí mismo. A Gustavo, por la confianza ciega y estar siempre predispuesto a darme una mano. A los dos les agradezco sus enseñanzas, sobre todo a través del ejemplo. A los Yamamitas, los Exmamitas y los Newmamitas. Sin lugar a dudas lo mejor del laboratorio! A Feli, Vir, Ceci, Leo, Agus, Pau, Lau, Lucho, Renato, Santi, Flor y Ale. Gracias por llenar los días de diversión. En particular quiero agradecerles a: Leo por ser un dolor de cabeza constante, una fuente inagotable de generación de ira y la persona que más confío del laboratorio; a Agus, por haberme permitido ser tu director asistente, por confiar en mí y enseñarme tanto, lo mejor de mi doctorado! A todo el laboratorio de Neuroendocrinología del Crecimiento y la Reproducción: Pau Vissio, Pao, Maxi, Mariana, Julieta, Nacho, Pau Di Yorio, Tomás y Dani. Otra gran fuente de alegría! A las Paus
Load more

Recommended publications
  • Genome Sequences of Tropheus Moorii and Petrochromis Trewavasae, Two Eco‑Morphologically Divergent Cichlid Fshes Endemic to Lake Tanganyika C
    www.nature.com/scientificreports OPEN Genome sequences of Tropheus moorii and Petrochromis trewavasae, two eco‑morphologically divergent cichlid fshes endemic to Lake Tanganyika C. Fischer1,2, S. Koblmüller1, C. Börger1, G. Michelitsch3, S. Trajanoski3, C. Schlötterer4, C. Guelly3, G. G. Thallinger2,5* & C. Sturmbauer1,5* With more than 1000 species, East African cichlid fshes represent the fastest and most species‑rich vertebrate radiation known, providing an ideal model to tackle molecular mechanisms underlying recurrent adaptive diversifcation. We add high‑quality genome reconstructions for two phylogenetic key species of a lineage that diverged about ~ 3–9 million years ago (mya), representing the earliest split of the so‑called modern haplochromines that seeded additional radiations such as those in Lake Malawi and Victoria. Along with the annotated genomes we analysed discriminating genomic features of the study species, each representing an extreme trophic morphology, one being an algae browser and the other an algae grazer. The genomes of Tropheus moorii (TM) and Petrochromis trewavasae (PT) comprise 911 and 918 Mbp with 40,300 and 39,600 predicted genes, respectively. Our DNA sequence data are based on 5 and 6 individuals of TM and PT, and the transcriptomic sequences of one individual per species and sex, respectively. Concerning variation, on average we observed 1 variant per 220 bp (interspecifc), and 1 variant per 2540 bp (PT vs PT)/1561 bp (TM vs TM) (intraspecifc). GO enrichment analysis of gene regions afected by variants revealed several candidates which may infuence phenotype modifcations related to facial and jaw morphology, such as genes belonging to the Hedgehog pathway (SHH, SMO, WNT9A) and the BMP and GLI families.
    [Show full text]
  • Paternity of Subordinates Raises Cooperative Effort in Cichlids
    Paternity of Subordinates Raises Cooperative Effort in Cichlids Rick Bruintjes1,2*, Danielle Bonfils1, Dik Heg1,3, Michael Taborsky1 1 Department of Behavioural Ecology, Institute of Ecology and Evolution, University of Bern, Hinterkappelen, Switzerland, 2 School of Biological Sciences, University of Bristol, Bristol, United Kingdom, 3 Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland Abstract Background: In cooperative breeders, subordinates generally help a dominant breeding pair to raise offspring. Parentage studies have shown that in several species subordinates can participate in reproduction. This suggests an important role of direct fitness benefits for cooperation, particularly where groups contain unrelated subordinates. In this situation parentage should influence levels of cooperation. Here we combine parentage analyses and detailed behavioural observations in the field to study whether in the highly social cichlid Neolamprologus pulcher subordinates participate in reproduction and if so, whether and how this affects their cooperative care, controlling for the effect of kinship. Methodology/Principal Findings: We show that: (i) male subordinates gained paternity in 27.8% of all clutches and (ii) if they participated in reproduction, they sired on average 11.8% of young. Subordinate males sharing in reproduction showed more defence against experimentally presented egg predators compared to subordinates not participating in reproduction, and they tended to stay closer to the breeding shelter. No effects of relatedness between subordinates and dominants (to mid-parent, dominant female or dominant male) were detected on parentage and on helping behaviour. Conclusions/Significance: This is the first evidence in a cooperatively breeding fish species that the helping effort of male subordinates may depend on obtained paternity, which stresses the need to consider direct fitness benefits in evolutionary studies of helping behaviour.
    [Show full text]
  • The Use of Different Sensory Modalities in Predator Discrimination
    Behav Ecol Sociobiol (2017) 71: 143 DOI 10.1007/s00265-017-2371-8 ORIGINAL ARTICLE Smell or vision? The use of different sensory modalities in predator discrimination Stefan Fischer1,2,3 & Evelyne Oberhummer1 & Filipa Cunha-Saraiva1,4 & Nina Gerber1,5 & Barbara Taborsky1 Received: 6 November 2016 /Revised: 19 August 2017 /Accepted: 28 August 2017 /Published online: 8 September 2017 # The Author(s) 2017. This article is an open access publication Abstract to a standardized threat stimulus combined with either preda- Theory predicts that animals should adjust their escape re- tor or non-predator cues presented either visually or chemical- sponses to the perceived predation risk. The information ani- ly. We predicted that flight responses towards a threat stimulus mals obtain about potential predation risk may differ qualita- are more pronounced if cues of dangerous rather than harm- tively depending on the sensory modality by which a cue is less heterospecifics are presented and that N. pulcher,beingan perceived. For instance, olfactory cues may reveal better in- aquatic species, relies more on olfaction when discriminating formation about the presence or absence of threats, whereas between dangerous and harmless heterospecifics. N. pulcher visual information can reliably transmit the position and po- responded faster to the threat stimulus, reached a refuge faster tential attack distance of a predator. While this suggests a and entered a refuge more likely when predator cues were differential use of information perceived through the two sen- perceived. Unexpectedly, the sensory modality used to per- sory channels, the relative importance of visual vs. olfactory ceive the cues did not affect the escape response or the dura- cues when distinguishing between different predation threats tion of the recovery phase.
    [Show full text]
  • Testing the Potential of Environmental DNA Methods for Surveying Lake Tanganyika's Highly Diverse Fish Communities Christopher J
    Testing the potential of environmental DNA methods for surveying Lake Tanganyika's highly diverse fish communities Christopher James Doble A thesis submitted for the degree of Doctor of Philosophy Department of Genetics, Evolution and Environment University College London April 2020 1 Declaration I, Christopher James Doble, confirm the work presented in this thesis is my own. Where information has been derived from other sources, I confirm this has been indicated in the thesis. Christopher James Doble Date: 27/04/2020 2 Statement of authorship I planned and undertook fieldwork to the Kigoma region of Lake Tanganyika, Tanzania in 2016 and 2017. This included obtaining research permits, collecting environmental DNA samples and undertaking fish community visual survey data used in Chapters three and four. For Chapter two, cichlid reference database sequences were sequenced by Walter Salzburger’s research group at the University of Basel. I extracted required regions from mitochondrial genome alignments during a visit to Walter’s research group. Other reference sequences were obtained by Sanger sequencing. I undertook the DNA extractions and PCR amplifications for all samples, with the clean-up and sequencing undertaken by the UCL Sequencing facility. I undertook the method development, DNA extractions, PCR amplifications and library preparations for each of the next generation sequencing runs in Chapters three and four at the NERC Biomolecular Analysis Facility Sheffield. Following training by Helen Hipperson at the NERC Biomolecular Analysis Facility in Sheffield, I undertook the bioinformatic analysis of sequence data in Chapters three and four. I also carried out all the data analysis within each chapter. Chapters two, three and parts of four have formed a manuscript recently published in Environmental DNA (Doble et al.
    [Show full text]
  • Lunar and Diurnal Cycles in Reproductive Physiology and Behavior in a Natural Population of Cooperatively Breeding Fish J
    Journal of Zoology Journal of Zoology. Print ISSN 0952-8369 Lunar and diurnal cycles in reproductive physiology and behavior in a natural population of cooperatively breeding fish J. K. Desjardins1,2, J. L. Fitzpatrick3,4, K. A. Stiver5,2, G. J. Van Der Kraak6 & S. Balshine2 1 Department of Biology, Stanford University, Stanford, CA, USA 2 Animal Behaviour Group, Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, ON, Canada 3 Centre for Evolutionary Biology, University of Western Australia, Crawley, Australia 4 Department of Biology, McMaster University, Hamilton, ON, Canada 5 Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA 6 College of Biological Sciences, University of Guelph, Guelph, ON, Canada Keywords Abstract Lake Tanganyika; lunar phase; Neolamprologus pulcher; sperm swimming Natural environmental periodicity that occurs on both the small scale like day speed; cichlidae; testosterone; length, or larger scale like lunar light can provide animals with valuable informa- 11-ketotestosterone. tion about resource availability and predation risk. Such environmental cycles are often linked to the timing of reproduction. Here, using the circulating androgen Correspondence concentrations, gonadal investment patterns and detailed behavioral observations Julie K. Desjardins, Department of Biology, we show that wild populations of the group-living cichlid, Neolamprologus pulcher 371 Serra Mall, Stanford University, from Lake Tanganyika, have marked diurnal differences in behavior
    [Show full text]
  • Download (1147Kb)
    Supplementary Figure 1 | Phylogeny of East African cichlids based on a new multi- marker dataset. (a) Bayesian inference phylogeny with MrBayes. (b) Maximum likelihood phylogeny with GARLI and 500 bootstrap replicates. While most of the branches are supported with high posterior probabilities (a) and bootstrap values (b), the phylogenetic relationships among the more ancestral haplochromines – including Pseudocrenilabrus philander – are poorly supported and differ between the analyses. LM: Lake Malawi, LV: Lake Victoria, LT: Lake Tanganyika Supplementary Figure 2 | Synteny analysis of teleost fhl2 paralogs. Dotplots of the human FHL2 gene region on human chr2 (100-220Mb) shows double conserved synteny to the two fhl2 paralogons in (a) medaka on chromosomes Ola21 (fhl2a) and Ola2 (fhl2b) and in (b) zebrafish on chromosomes Dre9 (fhl2b) and Dre6 (fhl2b). These chromosomes were previously shown to be derived from the ancestral chromosome c and duplicated during the teleost genome duplication1,2. Supplementary Figure 3 | Gene expression profiling in the teleost Danio rerio and Oryzias latipes. (a) Relative quantification (RQ) of fhl2a and fhl2b gene expression in ten tissues in D. rerio (three replicates per tissue) (b) RQ of fhl2a and fhl2b gene expression in eleven tissues in O. latipes (three replicates per tissue). In both species, gill tissue was used as reference. The error bars represent the standard error of the mean (SEM). In D. rerio (a) expression of fhl2a is higher in heart, eye, and oral jaw, although the expression of this gene copy is overall very low, especially when compared to the level of fhl2a expression in cichlids and O. latipes. Contrary to the scenario in cichlids (Fig.
    [Show full text]
  • Mating Systems in Cooperative Breeders : the Roles of Resource Dispersion and Conflict Mitigation
    Erschienen in: Behavioral Ecology ; 23 (2012), 3. - S. 521-530 https://dx.doi.org/10.1093/beheco/arr218 Mating systems in cooperative breeders: the roles of resource dispersion and conflict mitigation M. Y. L. Wong,a L. A. Jordan,b S. Marsh-Rollo,c S. St-Cyr,d J. O. Reynolds,e K. A. Stiver,f J. K. Desjardins,g J. L. Fitzpatrick,h and S. Balshinec aDepartment of Biology, Boston University, 5 Cummington Street, Boston, MA 02215, USA, bSchool of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia, cDepartment of Psychology, Neuroscience and Behaviour, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada, dDepartment of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Ontario M5S 3B2, Canada, eVancouver Aquarium, 845 Avison Way, Vancouver, British Columbia V6G 3E2, Canada, fDepartment of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06520, USA, gDepartment of Biology, Stanford University, Stanford, Gilbert Hall, CA 94305, USA, and hCentre for Evolutionary Biology, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia Within animal societies, the ecological and social underpinnings of mating system variation can be related to resource dispersion, sexual conflict between breeders, and the effects of non breeders. Here, we conducted a broad scale investigation into the evolution of mating systems in the cooperatively breeding cichlid, Neolamprologus pulcher, a species that exhibits both monogamy and polygyny within populations. Using long term field data, we showed that polygynous groups were more spatially clustered and held by larger competitively superior males than were monogamous groups, supporting the role of resource dispersion.
    [Show full text]
  • Strategic and Tactical Fighting Decisions in Cichlid Fishes With
    Behaviour 151 (2014) 47–71 brill.com/beh Strategic and tactical fighting decisions in cichlid fishes with divergent social systems a b b, Kristina Hick , Adam R. Reddon , Constance M. O’Connor ∗ and Sigal Balshine b a Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada L8S 4K1 b Department of Psychology, Neuroscience & Behaviour, McMaster University, 1280 Main Street West, Hamilton, ON, Canada L8S 4K1 *Corresponding author’s e-mail address: [email protected] Accepted 9 August 2013; published online 2 October 2013 Abstract The costs and benefits of engaging in a contest will differ depending on the social situation of the individuals involved. Therefore, understanding contest behaviour can help to elucidate the trade- offs of living in differing social systems and shed light on the evolution of social behaviour. In the current study, we compared contest behaviour in two closely related species of Lamprologine cichlid fish. Neolamprologus pulcher and Telmatochromis temporalis are both pair-breeding cich- lids, but N. pulcher are highly social, group-living fish, while T. temporalis display no grouping behaviour. To examine how competition varies by species, sex and familiarity, we staged same-sex conspecific contests over a shelter, a resource that is highly valued by both species, where contes- tants were either familiar or unfamiliar to one another. When we examined tactical and strategic components of these contests, we found that the highly social species had shorter contests and engaged in fewer costly aggressive acts than did the non-social species. Individuals of the highly social species were also more likely to resolve conflicts through the use of submissive displays, while individuals of the non-social species were more likely to flee from conflict.
    [Show full text]
  • CARES Exchange April 2017 2 GS CD 4-16-17 1
    The CARES Exchange Volume I Number 2 CARESCARES AreaArea ofof ConcernConcern LakeLake MalawiMalawi April 2017 CARESCARES ClubClub DataData SubmissionSubmission isis AprilApril 30th!30th! TheThe DirectoryDirectory ofof AvailableAvailable CARESCARES SpeciesSpecies NewestNewest AdditionsAdditions toto thethe CARESCARES TeamTeam NewNew EnglandEngland CichlidCichlid AssociationAssociation CARESCARES 2 Welcome to the The CARES Exchange. The pri- CARES, review the ‘CARES Startup’ tab on the web- mary intent of this publication is to make available a site CARESforfish.org, then contact Klaus Steinhaus listing of CARES fish from the CARES membership at [email protected]. to those that may be searching for CARES species. ___________________________________________ This issue of The Exchange was release to coincide It is important to understand that all transactions are with the due date for CARES Member Clubs to make between the buyer and seller and CARES in no way your data submissions. All submissions must be sub- moderates any exchanges including shipping prob- mitted by April 30th in the new file format. Learn lems, refunds, or bad blood between the two parties. more on page 7. This directory merely provides an avenue to which CARES fish may be located. As with all sales, be cer- Pam Chin explains the stressors affecting Lake Ma- tain that all the elements of the exchange are worked lawi. Pay close attention to what is going on there! out before purchasing or shipping. Take your CARES role seriously. Without your ef- forts, the fish we enjoy today might not be around to- No hybrids will knowingly be listed. morrow, There is no cost to place a for sale ad.
    [Show full text]
  • The Taxonomic Diversity of the Cichlid Fish Fauna of Ancient Lake
    JGLR-01482; No. of pages: 12; 4C: Journal of Great Lakes Research xxx (xxxx) xxx Contents lists available at ScienceDirect Journal of Great Lakes Research journal homepage: www.elsevier.com/locate/jglr Review The taxonomic diversity of the cichlid fish fauna of ancient Lake Tanganyika, East Africa Fabrizia Ronco ⁎, Heinz H. Büscher, Adrian Indermaur, Walter Salzburger Zoological Institute, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland article info abstract Article history: Ancient Lake Tanganyika in East Africa houses the world's ecologically and morphologically most diverse assem- Received 29 January 2019 blage of cichlid fishes, and the third most species-rich after lakes Malawi and Victoria. Despite long-lasting scien- 10 April 2019 tific interest in the cichlid species flocks of the East African Great Lakes, for example in the context of adaptive Accepted 29 April 2019 radiation and explosive diversification, their taxonomy and systematics are only partially explored; and many Available online xxxx cichlid species still await their formal description. Here, we provide a current inventory of the cichlid fish Communicated by Björn Stelbrink fauna of Lake Tanganyika, providing a complete list of all valid 208 Tanganyikan cichlid species, and discuss the taxonomic status of more than 50 undescribed taxa on the basis of the available literature as well as our Keywords: own observations and collections around the lake. This leads us to conclude that there are at least 241 cichlid spe- Biodiversity cies present in Lake Tanganyika, all but two are endemic to the basin. We finally summarize some of the major Ichthyodiversity taxonomic challenges regarding Lake Tanganyika's cichlid fauna.
    [Show full text]
  • Social Control of Spermatogenesis and Steroidogenesis in Cichlid Fish: a Comparative Approach
    159 1 REPRODUCTIONREVIEW Social control of spermatogenesis and steroidogenesis in cichlid fish: a comparative approach María Florencia Scaia1,2, Luciano Cavallino1,2 and Matías Pandolfi1,2 1Instituto de Biodiversidad y Biología Experimental y Aplicada – CONICET, Ciudad Autónoma de Buenos Aires, Argentina and 2Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina Correspondence should be addressed to M Pandolfi; Email: [email protected] Abstract Social animals with hierarchical dominance systems are susceptible to changes their environment. Interactions with conspecifics can greatly affect individual’s behavior and reproductive success. This review will show how social behavior modulates gonadal steroidogenesis and spermatogenesis in African and Neotropical cichlid fish with different social systems and how this modulation regulates reproductive capacity. Social behavior and aggressiveness are strongly linked to sex steroids, glucocorticoids and neuropeptides. The challenge hypothesis suggests that behavioral interactions increase androgen levels in response to social instability, but there is little evidence regarding estradiol levels. It has been recently demonstrated that in male Cichlasoma dimerus, a Neotropical cichlid fish, the challenge hypothesis could also be extended to estrogens. In C. dimerus, dominant males have higher gonadosomatic index than subordinated; the percentage of spermatocytes and spermatids is higher in subordinates, while dominants show a greater percentage of spermatozoa. In other species of African cichlids, socially suppressed subordinate males are not reproductively incompetent maintaining some activity at every level of their reproductive axis. Axis reactivation upon social ascent is similar to the initiation of puberty in mammals, as well as the reoccurrence of puberty observed in seasonally breeding animals.
    [Show full text]
  • Parallel Evolution of Facial Stripe Patterns in the Neolamprologus Brichardi/Pulcher Species Complex Endemic to Lake Tanganyika
    Available online at www.sciencedirect.com Molecular Phylogenetics and Evolution 45 (2007) 706–715 www.elsevier.com/locate/ympev Parallel evolution of facial stripe patterns in the Neolamprologus brichardi/pulcher species complex endemic to Lake Tanganyika Nina Duftner a,b,c, Kristina M. Sefc a, Stephan Koblmu¨ller a, Walter Salzburger d,f, Michael Taborsky e, Christian Sturmbauer a,* a Department of Zoology, University of Graz, Universita¨tsplatz 2, A-8010 Graz, Austria b FAS Center for Systems Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138, USA c Section of Integrative Biology, University of Texas at Austin, 1 University Station #C0930, Austin, TX 78712, USA d Department of Ecology and Evolution (DEE), University of Lausanne, UNIL Sorge, Le Biophore, CH-1015 Lausanne, Switzerland e Department of Behavioural Ecology, Zoological Institute, University of Bern, CH-3032 Hinterkappelen, Switzerland f Zoological Institute/Evolutionary Biology, University of Basel, Vesalgasse 1, CH-4051 Basel, Switzerland Received 6 March 2007; revised 2 August 2007; accepted 7 August 2007 Available online 15 August 2007 Abstract Colour pattern diversity can be due to random processes or to natural or sexual selection. Consequently, similarities in colour patterns are not always correlated with common ancestry, but may result from convergent evolution under shared selection pressures or drift. Neolamprologus brichardi and Neolamprologus pulcher have been described as two distinct species based on differences in the arrangement of two dark bars on the operculum. Our study uses DNA sequences of the mitochondrial control region to show that relatedness of hapl- otypes disagrees with species assignment based on head colour pattern.
    [Show full text]