1
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Bass AH. A tale of two males: Behavioral and neural mechanisms of alternative reproductive tactics in midshipman fish. Horm Behav 2024; 161:105507. [PMID: 38479349 DOI: 10.1016/j.yhbeh.2024.105507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/10/2024] [Accepted: 02/14/2024] [Indexed: 05/04/2024]
Abstract
An amalgam of investigations at the interface of neuroethology and behavioral neuroendocrinology first established the most basic behavioral, neuroanatomical, and neurophysiological characters of vocal-acoustic communication morphs in the plainfin midshipman fish, Porichthys notatus Girard. This foundation has led, in turn, to the repeated demonstration that neuro-behavioral mechanisms driving reproductive-related, vocal-acoustic behaviors can be uncoupled from gonadal state for two adult male phenotypes that follow alternative reproductive tactics (ARTs).
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Affiliation(s)
- Andrew H Bass
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
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2
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Allen A, Heisler E, Kittelberger JM. Dopamine injections to the midbrain periaqueductal gray inhibit vocal-motor production in a teleost fish. Physiol Behav 2023; 263:114131. [PMID: 36796532 DOI: 10.1016/j.physbeh.2023.114131] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/11/2023] [Accepted: 02/13/2023] [Indexed: 02/16/2023]
Abstract
Across vertebrates, the midbrain periaqueductal gray (PAG) plays a critical role in social and vocal behavior. Dopaminergic neurotransmission also modulates these behaviors, and dopaminergic innervation of the PAG has been well documented. Nonetheless, the potential role of dopamine in shaping vocal production at the level of the PAG is not well understood. Here, we tested the hypothesis that dopamine modulates vocal production in the PAG, using a well-characterized vertebrate model system for the study of vocal communication, the plainfin midshipman fish, Porichthys notatus. We found that focal dopamine injections to the midshipman PAG rapidly and reversibly inhibited vocal production triggered by stimulation of known vocal-motor structures in the preoptic area / anterior hypothalamus. While dopamine inhibited vocal-motor output, it did not alter behaviorally-relevant parameters of this output, such as vocalization duration and frequency. Dopamine-induced inhibition of vocal production was prevented by the combined blockade of D1- and D2-like receptors but was unaffected by isolated blockade of either D1-receptors or D2-receptors. Our results suggest dopamine neuromodulation in the midshipman PAG may inhibit natural vocal behavior, in courtship and/or agonistic social contexts.
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Affiliation(s)
- Alexander Allen
- Department of Biology, Gettysburg College, Gettysburg, PA 17325, United States
| | - Elizabeth Heisler
- Department of Biology, Gettysburg College, Gettysburg, PA 17325, United States
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3
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Zeeman AN, Smallegange IM, Steel EB, Groot AT, Stewart KA. Toward an understanding of the chemical ecology of alternative reproductive tactics in the bulb mite (Rhizoglyphus robini). BMC Ecol Evol 2022; 22:5. [PMID: 34998364 PMCID: PMC8742560 DOI: 10.1186/s12862-021-01956-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 12/22/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Under strong sexual selection, certain species evolve distinct intrasexual, alternative reproductive tactics (ARTs). In many cases, ARTs can be viewed as environmentally-cued threshold traits, such that ARTs coexist if their relative fitness alternates over the environmental cue gradient. Surprisingly, the chemical ecology of ARTs has been underexplored in this context. To our knowledge, no prior study has directly quantified pheromone production for ARTs in a male-polymorphic species. Here, we used the bulb mite-in which males are either armed fighters that kill conspecifics, or unarmed scramblers (which have occasionally been observed to induce mating behavior in other males)-as a model system to gain insight into the role of pheromones in the evolutionary maintenance of ARTs. Given that scramblers forgo investment into weaponry, we tested whether scramblers produce higher quantities of the putative female sex-pheromone α-acaridial than fighters, which would improve the fitness of the scrambler phenotype through female mimicry by allowing avoidance of aggression from competitors. To this end, we sampled mites from a rich and a poor nutritional environment and quantified their production of α-acaridial through gas chromatography analysis. RESULTS We found a positive relationship between pheromone production and body size, but males exhibited a steeper slope in pheromone production with increasing size than females. Females exhibited a higher average pheromone production than males. We found no significant difference in slope of pheromone production over body size between fighters and scramblers. However, scramblers reached larger body sizes and higher pheromone production than fighters, providing some evidence for a potential female mimic strategy adopted by large scramblers. Pheromone production was significantly higher in mites from the rich nutritional environment than the poor environment. CONCLUSION Further elucidation of pheromone functionality in bulb mites, and additional inter- and intrasexual comparisons of pheromone profiles are needed to determine if the observed intersexual and intrasexual differences in pheromone production are adaptive, if they are a by-product of allometric scaling, or diet-mediated pheromone production under weak selection. We argue chemical ecology offers a novel perspective for research on ARTs and other complex life-history traits.
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Affiliation(s)
- Adam N Zeeman
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Isabel M Smallegange
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Emily Burdfield Steel
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Astrid T Groot
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Kathryn A Stewart
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands.
- Institute of Environmental Sciences, Leiden University, Leiden, The Netherlands.
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Synyshyn C, Green-Pucella AE, Balshine S. Nonmating behavioural differences between male tactics in the invasive round goby. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Cartolano MC, Babcock EA, McDonald MD. Evidence that Gulf toadfish use pulsatile urea excretion to communicate social status. Physiol Behav 2020; 227:113182. [PMID: 32976848 DOI: 10.1016/j.physbeh.2020.113182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/10/2020] [Accepted: 09/21/2020] [Indexed: 10/23/2022]
Abstract
Gulf toadfish (Opsanus beta), a highly territorial marine teleost species, are believed to communicate through chemicals released across the gill during pulsatile urea excretion. While freshwater teleost and crustacean urinary signals have been shown to relay information about dominance to reduce physical aggression in future encounters, the use of chemical signals to convey social status in marine teleosts is understudied. Behavior and urea excretion patterns were monitored in pairs of male toadfish during an initial agonistic encounter and in a 2nd encounter where a subset of pairs had their nares blocked to determine how olfaction, and thus chemical communication, play a role in establishing dominance. Anosmic toadfish did not experience increases in aggressive behavior, unlike other species previously studied. However, behavior and the pattern of urea excretion were disrupted in anosmic pairs compared to control pairs. Specifically, control subordinate fish had an increase in their dominance index during the 2nd encounter, a response that anosmic subordinate fish did not experience suggesting that without the ability to smell, subordinate fish cannot recognize their opponent and assess their fighting ability and have a reduced chance of winning. These anosmic subordinate fish also had an increase in pulse frequency, perhaps reflecting an increased effort in communication of status. Future research is needed to conclude if peaks in agonistic behavior are coordinated around the time of urea pules. However, the observed changes in behavior and pulsatile urea excretion due to anosmia in the present study provide evidence that toadfish use pulsatile urea excretion to release signals for chemical communication during agonistic encounters.
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Affiliation(s)
- Maria C Cartolano
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA.
| | - Elizabeth A Babcock
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
| | - M Danielle McDonald
- Department of Marine Biology and Ecology, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
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Liesch N, Ladich F. Both sexes produce sounds in vocal fish species: testing the hypothesis in the pygmy gourami (labyrinth fishes). J Exp Biol 2020; 223:jeb223750. [PMID: 32300049 DOI: 10.1242/jeb.223750] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/06/2020] [Indexed: 11/20/2022]
Abstract
In vocal fish species, males possess larger sound-generating organs and signal acoustically with pronounced sex-specific differences. Sound production is known in two out of three species of croaking gouramis (Trichopsis vittata and T. schalleri). The present study investigates sex-specific differences in sonic organs, vocalizing behaviour and sounds emitted in the third species, the pygmy gourami, T. pumila, in order to test the hypothesis that females are able to vocalize despite their less-developed sonic organs, and despite contradictory reports. Croaking gouramis stretch and pluck two enhanced (sonic) pectoral fin tendons during alternate fin beating, resulting in a series of double-pulsed bursts, termed croaking sound. We measured the diameter of the first and second sonic tendon and showed that male tendons were twice as large as in similar-sized females. We also determined the duration of dyadic contests, visual displays, number of sounds and buttings. Sexes differ in all sound characteristics but in no behavioural variable. Male sounds consisted of twice as many bursts, a higher percentage of double-pulsed bursts and a higher burst period. Additionally, male sounds had a lower dominant frequency and a higher sound level. In summary, female pygmy gouramis possessed sonic organs and vocalized in most dyadic contests. The sexual dimorphism in sonic tendons is clearly reflected in sex-specific differences in sound characteristics, but not in agonistic behaviour, supporting the hypothesis that females are vocal.
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Affiliation(s)
- Noémie Liesch
- Department of Behavioural Biology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Friedrich Ladich
- Department of Behavioural Biology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
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Tripp JA, Feng NY, Bass AH. Behavioural tactic predicts preoptic-hypothalamic gene expression more strongly than developmental morph in fish with alternative reproductive tactics. Proc Biol Sci 2019; 285:rspb.2017.2742. [PMID: 29343607 DOI: 10.1098/rspb.2017.2742] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 12/19/2017] [Indexed: 12/19/2022] Open
Abstract
Reproductive success relies on the coordination of social behaviours, such as territory defence, courtship and mating. Species with extreme variation in reproductive tactics are useful models for identifying the neural mechanisms underlying social behaviour plasticity. The plainfin midshipman (Porichthys notatus) is a teleost fish with two male reproductive morphs that follow widely divergent developmental trajectories and display alternative reproductive tactics (ARTs). Type I males defend territories, court females and provide paternal care, but will resort to cuckoldry if they cannot maintain a territory. Type II males reproduce only through cuckoldry. We sought to disentangle gene expression patterns underlying behavioural tactic, in this case ARTs, from those solely reflective of developmental morph. Using RNA-sequencing, we investigated differential transcript expression in the preoptic area-anterior hypothalamus (POA-AH) of courting type I males, cuckolding type I males and cuckolding type II males. Unexpectedly, POA-AH differential expression was more strongly coupled to behavioural tactic than morph. This included a suite of transcripts implicated in hormonal regulation of vertebrate social behaviour. Our results reveal that divergent expression patterns in a conserved neuroendocrine centre known to regulate social-reproductive behaviours across vertebrate lineages may be uncoupled from developmental history to enable plasticity in the performance of reproductive tactics.
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Affiliation(s)
- Joel A Tripp
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853-7901, USA
| | - Ni Y Feng
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853-7901, USA
| | - Andrew H Bass
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853-7901, USA
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Ladich F, Schleinzer G. Sound production in female Trichopsis schalleri (Labyrinth fishes): comparison to males and evolutionary considerations. BIOACOUSTICS 2018; 29:123-139. [PMID: 32257627 PMCID: PMC7077349 DOI: 10.1080/09524622.2018.1555773] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 12/01/2018] [Indexed: 12/30/2022]
Abstract
Croaking gouramis (genus Trichopsis, Anabantoidei) generate series of two-pulsed bursts (croaks) during agonistic interactions. Sex-specific differences are minor in T. vittata which raises the question whether sexes differ in the other two species. The current study analyses sounds recorded in female T. schalleri, compares the sound characteristics to those of males investigated earlier and correlates these characteristics to female body size. Sex-specific differences were found in three out of six sound characteristics. In females, sounds were lower in burst number, burst period and SPL. Pulse period, dominant frequency and peak-to-peak amplitude ratios of pulses did not differ between sexes. Burst period and SPL increased significantly with female body weight, whereas dominant frequency decreased. The present acoustic data indicate the sex-specific differences are more pronounced in T. schalleri than T. vittata. The results also demonstrate that both sexes are vocal, which remains to be shown for females of the third species, T. pumila, which have poorly developed sonic organs. The evolution of the pectoral sound-producing mechanism in Trichopsis is most likely based on an exaptation process during which acoustic signals are generated by fin tendons initially related to other functions as is evident in closely related genera lacking this organ.
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Affiliation(s)
- Friedrich Ladich
- Department of Behavioural Biology, University of Vienna, Vienna, Austria
| | - Günter Schleinzer
- Department of Behavioural Biology, University of Vienna, Vienna, Austria
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Ghahramani ZN, Timothy M, Kaur G, Gorbonosov M, Chernenko A, Forlano PM. Catecholaminergic Fiber Innervation of the Vocal Motor System Is Intrasexually Dimorphic in a Teleost with Alternative Reproductive Tactics. BRAIN, BEHAVIOR AND EVOLUTION 2015; 86:131-44. [PMID: 26355302 DOI: 10.1159/000438720] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 07/13/2015] [Indexed: 01/10/2023]
Abstract
Catecholamines, which include the neurotransmitters dopamine and noradrenaline, are known modulators of sensorimotor function, reproduction, and sexually motivated behaviors across vertebrates, including vocal-acoustic communication. Recently, we demonstrated robust catecholaminergic (CA) innervation throughout the vocal motor system in the plainfin midshipman fish Porichthys notatus, a seasonal breeding marine teleost that produces vocal signals for social communication. There are 2 distinct male reproductive morphs in this species: type I males establish nests and court females with a long-duration advertisement call, while type II males sneak spawn to steal fertilizations from type I males. Like females, type II males can only produce brief, agonistic, grunt type vocalizations. Here, we tested the hypothesis that intrasexual differences in the number of CA neurons and their fiber innervation patterns throughout the vocal motor pathway may provide neural substrates underlying divergence in reproductive behavior between morphs. We employed immunofluorescence (-ir) histochemistry to measure tyrosine hydroxylase (TH; a rate-limiting enzyme in catecholamine synthesis) neuron numbers in several forebrain and hindbrain nuclei as well as TH-ir fiber innervation throughout the vocal pathway in type I and type II males collected from nests during the summer reproductive season. After controlling for differences in body size, only one group of CA neurons displayed an unequivocal difference between male morphs: the extraventricular vagal-associated TH-ir neurons, located just lateral to the dimorphic vocal motor nucleus (VMN), were significantly greater in number in type II males. In addition, type II males exhibited greater TH-ir fiber density within the VMN and greater numbers of TH-ir varicosities with putative contacts on vocal motor neurons. This strong inverse relationship between the predominant vocal morphotype and the CA innervation of vocal motor neurons suggests that catecholamines may function to inhibit vocal output in midshipman. These findings support catecholamines as direct modulators of vocal behavior, and differential CA input appears reflective of social and reproductive behavioral divergence between male midshipman morphs.
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10
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Cogliati KM, Mistakidis AF, Marentette JR, Lau A, Bolker BM, Neff BD, Balshine S. Comparing population level sexual selection in a species with alternative reproductive tactics. Behav Ecol 2014. [DOI: 10.1093/beheco/aru147] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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11
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Coffin AB, Zeddies DG, Fay RR, Brown AD, Alderks PW, Bhandiwad AA, Mohr RA, Gray MD, Rogers PH, Sisneros JA. Use of the swim bladder and lateral line in near-field sound source localization by fish. ACTA ACUST UNITED AC 2014; 217:2078-88. [PMID: 24675557 DOI: 10.1242/jeb.093831] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We investigated the roles of the swim bladder and the lateral line system in sound localization behavior by the plainfin midshipman fish (Porichthys notatus). Reproductive female midshipman underwent either surgical deflation of the swim bladder or cryoablation of the lateral line and were then tested in a monopolar sound source localization task. Fish with nominally 'deflated' swim bladders performed similar to sham-deflated controls; however, post-experiment evaluation of swim bladder deflation revealed that a majority of 'deflated' fish (88%, seven of the eight fish) that exhibited positive phonotaxis had partially inflated swim bladders. In total, 95% (21/22) of fish that localized the source had at least partially inflated swim bladders, indicating that pressure reception is likely required for sound source localization. In lateral line experiments, no difference was observed in the proportion of females exhibiting positive phonotaxis with ablated (37%) versus sham-ablated (47%) lateral line systems. These data suggest that the lateral line system is likely not required for sound source localization, although this system may be important for fine-tuning the approach to the sound source. We found that midshipman can solve the 180 deg ambiguity of source direction in the shallow water of our test tank, which is similar to their nesting environment. We also found that the potential directional cues (phase relationship between pressure and particle motion) in shallow water differs from a theoretical free-field. Therefore, the general question of how fish use acoustic pressure cues to solve the 180 deg ambiguity of source direction from the particle motion vector remains unresolved.
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Affiliation(s)
- Allison B Coffin
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, USA Department of Otolaryngology - Head and Neck Surgery, University of Washington, Seattle, WA 98105, USA
| | | | - Richard R Fay
- Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Andrew D Brown
- Department of Speech and Hearing Sciences, University of Washington, Seattle, WA 98105, USA
| | - Peter W Alderks
- Department of Psychology, University of Washington, Seattle, WA 98195, USA
| | - Ashwin A Bhandiwad
- Department of Psychology, University of Washington, Seattle, WA 98195, USA
| | - Robert A Mohr
- Department of Psychology, University of Washington, Seattle, WA 98195, USA
| | - Michael D Gray
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Peter H Rogers
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Joseph A Sisneros
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195, USA Department of Psychology, University of Washington, Seattle, WA 98195, USA Department of Biology, University of Washington, Seattle, WA 98195, USA
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12
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Kelly AM, Goodson JL. Functional significance of a phylogenetically widespread sexual dimorphism in vasotocin/vasopressin production. Horm Behav 2013; 64:840-6. [PMID: 24100197 DOI: 10.1016/j.yhbeh.2013.09.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 09/11/2013] [Accepted: 09/12/2013] [Indexed: 10/26/2022]
Abstract
Male-biased production of arginine vasotocin/vasopressin (VT/VP) in the medial bed nucleus of the stria terminalis (BSTm) represents one of the largest and most phylogenetically widespread sexual dimorphisms in the vertebrate brain. Although this sex difference was identified 30 years ago, the function of the dimorphism has yet to be determined. Because 1) rapid transcriptional activation of BSTm VT/VP neurons is observed selectively in response to affiliation-related stimuli, 2) BSTm VT/VP content and release correlates negatively with aggression, and 3) BSTm VT/VP production is often limited to periods of reproduction, we hypothesized that the sexual dimorphism serves to promote male-specific reproductive behaviors and offset male aggression in the context of reproductive affiliation. We now show that antisense knockdown of BSTm VT production in colony-housed finches strongly increases aggression in a male-specific manner and concomitantly reduces courtship. Thus, the widespread dimorphism may serve to focus males on affiliation in appropriate reproductive contexts (e.g., when courting) while concomitantly offsetting males' tendency for greater aggression relative to females.
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Affiliation(s)
- Aubrey M Kelly
- Department of Biology, Indiana University, Bloomington, IN 47405, USA.
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Chishti YZ, Feswick A, Munkittrick KR, Martyniuk CJ. Transcriptomic profiling of progesterone in the male fathead minnow (Pimephales promelas) testis. Gen Comp Endocrinol 2013; 192:115-25. [PMID: 23665105 DOI: 10.1016/j.ygcen.2013.04.033] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 04/23/2013] [Accepted: 04/28/2013] [Indexed: 12/16/2022]
Abstract
P4 is a hormone with diverse functions that include roles in reproduction, growth, and development. The objectives of this study were to examine the effects of P4 on androgen production in the mature teleost testis and to identify molecular signaling cascades regulated by P4 to improve understanding of its role in male reproduction. Fathead minnow (FHM) testis explants were treated in vitro with two concentrations of P4 (10(-8) and 10(-6) M) for 6 and 12 h. P4 significantly increased testosterone (T) production in the FHM testis but did not affect 11-ketotestosterone. Gene network analysis revealed that insulin growth factor (Igf1) and tumor necrosis factor receptor (Tnfr) signaling was significantly depressed with P4 treatment after 12h. There was also a 20% increase in a gene network for follicle-stimulating hormone secretion and an 18% decrease in genes involved in vasopressin signaling. Genes in steroid metabolism (e.g. star, cyp19a, 11bhsd) were not significantly affected by P4 treatments in this study, and it is hypothesized that pre-existing molecular machinery may be more involved in the increased production of T rather than the de novo expression of steroid-related transcripts and receptors. There was a significant decrease in prostaglandin E synthase 3b (cytosolic) (ptges3b) after treatment with P4, suggesting that there is cross talk between P4 and prostaglandin pathways in the reproductive testis. P4 has a role in regulating steroid production in the male testis and may do so by modulating gene networks related to endocrine pathways, such as Igf1, Tnfr, and vasopressin.
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Key Words
- 11-KT
- 11-ketotestosterone
- 3-phosphoinositide dependent protein kinase-1
- AKT1
- APOE
- APP
- AR
- Androgens
- B-cell CLL/lymphoma 6
- BCL2-like 1
- BCL2L1
- BCL6
- BMP2
- BMP4
- CCAAT/enhancer binding protein (C/EBP), alpha
- CD40
- CD40 molecule, TNF receptor superfamily member 5
- CEBPA
- CHAT
- CPLA2
- CTSK
- CYP19a
- EGFR
- EPCAM
- ESR
- F2RL1
- FBJ murine osteosarcoma viral oncogene homolog
- FOS
- FOS-like antigen 1
- FOSL1
- FOXO1
- Gene set enrichment analysis
- HIF1A
- HSD11B2
- HSD17B1
- HSP70
- ID2
- IGF1
- IGF1R
- IGF2
- IGF2R
- IL12B
- INS
- IRS1
- ITGAV
- Insulin growth factor
- JAK1
- JAK2
- Janus kinase 1
- Janus kinase 2
- LOX
- MAP2K1
- MITF
- MMP9
- NAMPT
- NFKBIA
- NOS2
- P4
- PDPK1
- PI3K
- PIP3
- PLAT
- PTGES3B
- PTGS2
- Phosphatidylinositol (3,4,5)-triphosphate
- Phospholipase A2
- Progestogens
- RAC-α serine/threonine-protein kinase
- Runt
- SNEA
- SP1
- STAR
- STAT1
- STAT3
- STAT5A
- Sp1 transcription factor
- Sub-network enrichment analysis
- T
- TNFR adaptor protein
- TNFRAP
- TNFRSF11A
- TNFRSF11B
- TNFSF11
- TNFSF18
- Tumor necrosis factor
- XPR1
- amyloid β (A4) precursor protein
- androgen receptor
- apolipoprotein E
- bone morphogenetic protein 2
- bone morphogenetic protein 4
- cathepsin K
- choline O-acetyltransferase
- coagulation factor II (thrombin) receptor-like 1
- cytochrome P450 aromatase
- epidermal growth factor receptor
- epithelial cell adhesion molecule
- estrogen receptor
- forkhead box O1
- heat shock protein 70
- hydroxysteroid (11-β) dehydrogenase 2
- hydroxysteroid (17-β) dehydrogenase 1
- hypoxia inducible factor 1, α subunit (basic helix-loop-helix transcription factor)
- inhibitor of DNA binding 2
- insulin
- insulin receptor substrate 1
- insulin-like growth factor 1 (somatomedin C)
- insulin-like growth factor 1 receptor
- insulin-like growth factor 2 (somatomedin A)
- insulin-like growth factor 2 receptor
- integrin, alpha V (vitronectin receptor, alpha polypeptide, antigen CD51)
- interleukin 12B (natural killer cell stimulatory factor 2, cytotoxic lymphocyte maturation factor 2, p40)
- lysyl oxidase
- matrix metallopeptidase 9 (gelatinase B, 92kDa gelatinase, 92kDa type IV collagenase)
- microphthalmia-associated transcription factor
- mitogen-activated protein kinase kinase 1
- nicotinamide phosphoribosyltransferase
- nitric oxide synthase 2, inducible
- nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha
- phosphatidylinositol 3-kinase
- phosphatidylinositol 3-phosphate
- plasminogen activator, tissue
- progesterone
- prostaglandin E synthase 3
- prostaglandin-endoperoxide synthase 2 (prostaglandin G/H synthase and cyclooxygenase)
- signal transducer and activator of transcription 1, 91kDa
- signal transducer and activator of transcription 3 (acute-phase response factor)
- signal transducer and activator of transcription 5A
- steroidogenic acute regulatory protein
- sub-network enrichment analysis
- testosterone
- tumor necrosis factor (ligand) superfamily, member 11
- tumor necrosis factor (ligand) superfamily, member 18
- tumor necrosis factor receptor superfamily, member 11a, NFKB activator
- tumor necrosis factor receptor superfamily, member 11b
- xenotropic and polytropic retrovirus receptor 1
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Affiliation(s)
- Yasmin Z Chishti
- Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, New Brunswick, Canada E2L 4L5
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14
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Neff BD, Svensson EI. Polyandry and alternative mating tactics. Philos Trans R Soc Lond B Biol Sci 2013; 368:20120045. [PMID: 23339236 DOI: 10.1098/rstb.2012.0045] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Many species in the animal kingdom are characterized by alternative mating tactics (AMTs) within a sex. In males, such tactics include mate guarding versus sneaking behaviours, or territorial versus female mimicry. Although AMTs can occur in either sex, they have been most commonly described in males. This sex bias may, in part, reflect the increased opportunity for sexual selection that typically exists in males, which can result in a higher probability that AMTs evolve in that sex. Consequently, females and polyandry can play a pivotal role in governing the reproductive success associated with male AMTs and in the evolutionary dynamics of the tactics. In this review, we discuss polyandry and the evolution of AMTs. First, we define AMTs and review game theoretical and quantitative genetic approaches used to model their evolution. Second, we review several examples of AMTs, highlighting the roles that genes and environment play in phenotype expression and development of the tactics, as well as empirical approaches to differentiating among the mechanisms. Third, ecological and genetic constraints to the evolution of AMTs are discussed. Fourth, we speculate on why female AMTs are less reported on in the literature than male tactics. Fifth, we examine the effects of AMTs on breeding outcomes and female fitness, and as a source, and possibly also a consequence, of sexual conflict. We conclude by suggesting a new model for the evolution of AMTs that incorporates both environmental and genetic effects, and discuss some future avenues of research.
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Affiliation(s)
- Bryan D Neff
- Department of Biology, Western University, 1151 Richmond Street, London, Ontario, Canada.
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15
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16
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Riede T, Tokuda IT, Farmer CG. Subglottal pressure and fundamental frequency control in contact calls of juvenile Alligator mississippiensis. ACTA ACUST UNITED AC 2011; 214:3082-95. [PMID: 21865521 PMCID: PMC3160820 DOI: 10.1242/jeb.051110] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Vocalization is rare among non-avian reptiles, with the exception of the crocodilians, the sister taxon of birds. Crocodilians have a complex vocal repertoire. Their vocal and respiratory system is not well understood but appears to consist of a combination of features that are also found in the extremely vocal avian and mammalian taxa. Anatomical studies suggest that the alligator larynx is able to abduct and adduct the vocal folds, but not to elongate or shorten them, and is therefore lacking a key regulator of frequency, yet alligators can modulate fundamental frequency remarkably well. We investigated the morphological and physiological features of sound production in alligators. Vocal fold length scales isometrically across a wide range of alligator body sizes. The relationship between fundamental frequency and subglottal pressure is significant in some individuals at some isolated points, such as call onset and position of maximum fundamental frequency. The relationship is not consistent over large segments of the call. Fundamental frequency can change faster than expected by pressure changes alone, suggesting an active motor pattern controls frequency and is intrinsic to the larynx. We utilized a two-mass vocal fold model to test whether abduction and adduction could generate this motor pattern. The fine-tuned interplay between subglottal pressure and glottal adduction can achieve frequency modulations much larger than those resulting from subglottal pressure variations alone and of similar magnitude, as observed in alligator calls. We conclude that the alligator larynx represents a sound source with only two control parameters (subglottal pressure and vocal fold adduction) in contrast to the mammalian larynx in which three parameters can be altered to modulate frequency (subglottal pressure, vocal fold adduction and length/tension).
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Affiliation(s)
- Tobias Riede
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA.
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17
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Sakhai SA, Kriegsfeld LJ, Francis DD. Maternal programming of sexual attractivity in female Long Evans rats. Psychoneuroendocrinology 2011; 36:1217-25. [PMID: 21458163 PMCID: PMC3151476 DOI: 10.1016/j.psyneuen.2011.02.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 02/28/2011] [Accepted: 02/28/2011] [Indexed: 10/18/2022]
Abstract
In mammals, maternal care influences the developing offspring across multiple domains. In Long Evans rats, for example, the quality of maternal care received as a pup influences later cognitive function, neuroendocrine responses to stress and behavioral measures of emotionality. Data from humans, non-human primates, and rodents also suggest that early life events may similarly perturb measures of sexual reproduction, with possible consequences for reproductive fitness. The current study examined whether or not male conspecifics differentially prefer females, as adult mating partners, that were reared under varying maternal conditions (assessed via the quantity of licking and grooming received; LG). Additionally, the impact of maternal care on adult female sexual motivation and behavior were quantified to determine if these behavioral characteristics are associated with any preference observed. In a mate preference task, male rats chose, almost exclusively, to mount, copulate and ejaculate with female rats reared under Low LG conditions. Under non-paced mating conditions, female Low LG rats display significantly more paracopulatory and copulatory behaviors compared to High LG rats. Due to its critical role in female paracopulatory behavior, progesterone receptor immunoreactivity (PR-ir) in the ventromedial nucleus of the hypothalamus (VMH) was also assessed in both groups of female rats. Estradiol induced PR-ir in the VMH was significantly higher in Low LG relative to High LG rats. Together, these data suggests that early life parental care may developmentally program aspects of behavior and physiology that subsequently influence sexual attractivity and behavior in adult females.
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Affiliation(s)
- Samuel A Sakhai
- Department of Psychology, University of California at Berkeley, Berkeley, CA 94720, USA.
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18
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Brantley RK, Bass AH. Alternative Male Spawning Tactics and Acoustic Signals in the Plainfin Midshipman Fish Porichthys notatus Girard (Teleostei, Batrachoididae). Ethology 2010. [DOI: 10.1111/j.1439-0310.1994.tb01011.x] [Citation(s) in RCA: 269] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Bass AH, Remage-Healey L. Central pattern generators for social vocalization: androgen-dependent neurophysiological mechanisms. Horm Behav 2008; 53:659-72. [PMID: 18262186 PMCID: PMC2570494 DOI: 10.1016/j.yhbeh.2007.12.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2007] [Revised: 12/04/2007] [Accepted: 12/10/2007] [Indexed: 12/13/2022]
Abstract
Historically, most studies of vertebrate central pattern generators (CPGs) have focused on mechanisms for locomotion and respiration. Here, we highlight new results for ectothermic vertebrates, namely teleost fish and amphibians, showing how androgenic steroids can influence the temporal patterning of CPGs for social vocalization. Investigations of vocalizing teleosts show how androgens can rapidly (within minutes) modulate the neurophysiological output of the vocal CPG (fictive vocalizations that mimic the temporal properties of natural vocalizations) inclusive of their divergent actions between species, as well as intraspecific differences between male reproductive morphs. Studies of anuran amphibians (frogs) demonstrate that long-term steroid treatments (wks) can masculinize the fictive vocalizations of females, inclusive of its sensitivity to rapid modulation by serotonin. Given the conserved organization of vocal control systems across vertebrate groups, the vocal CPGs of fish and amphibians provide tractable models for identifying androgen-dependent events that are fundamental to the mechanisms of vocal motor patterning. These basic mechanisms can also inform our understanding of the more complex CPGs for vocalization, and social behaviors in general, that have evolved among birds and mammals.
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Affiliation(s)
- Andrew H Bass
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
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20
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Bass AH. Steroid-dependent plasticity of vocal motor systems: Novel insights from teleost fish. ACTA ACUST UNITED AC 2008; 57:299-308. [PMID: 17524490 DOI: 10.1016/j.brainresrev.2007.04.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2007] [Revised: 04/18/2007] [Accepted: 04/18/2007] [Indexed: 11/28/2022]
Abstract
Vocal communication is a trait shared by most vertebrates. Non-mammalian model systems have provided exquisite examples of how motor and sensory systems, respectively, produce and encode the physical attributes of acoustic communication signals that play essential roles in mediating the dynamics of social behavior. These same models, mainly developed for a few species of fish, amphibians and birds, have proven to be equally important for demonstrating how steroids and other hormones shape the neural mechanisms of vocal communication. This review mainly considers recent studies in teleost fish demonstrating the role of steroids in the rapid modulation of the firing properties of a central pattern generator for vocalization. Thus, steroids, like other classes of neurochemicals, can play an instrumental role in reshaping the neurophysiological coding of motor patterning, in this case for social signaling behavior.
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Affiliation(s)
- A H Bass
- Department of Neurobiology and Behavior, Seeley G. Mudd Hall, Cornell University, Ithaca, NY 14853, USA.
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21
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Voigt C, Leitner S, Gahr M. Socially induced brain differentiation in a cooperatively breeding songbird. Proc Biol Sci 2007; 274:2645-51. [PMID: 17785271 PMCID: PMC2279217 DOI: 10.1098/rspb.2007.0858] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Birds living in social groups establish dominance hierarchies, and taking up the dominant position influences behaviour and physiological parameters. In cooperatively breeding white-browed sparrow weavers (Plocepasser mahali), the transition from subordinate helper to dominant breeder male induces the production of a new type of song. This song contains a large number of new syllables and differs in temporal pattern from duet songs produced by all other group members. Here we show that this change in social status of adult males affects the morphology of a behavioural control circuit, the song control system of songbirds that is composed of large neuron populations. The volume of the song control areas HVC and RA and their gene-expression levels depend on males' social status. Dominant males have several times larger testes than subordinates, which is not reflected in circulating androgen and oestrogen levels. Our findings suggest a remarkable differentiation of adult vertebrate brains in relation to changing social cues.
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Affiliation(s)
- Cornelia Voigt
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology82319 Seewiesen, Germany
| | - Stefan Leitner
- School of Biological Sciences, Royal Holloway University of LondonEgham, Surrey TW20 0EX, UK
- Author for correspondence ()
| | - Manfred Gahr
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology82319 Seewiesen, Germany
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22
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Leitner S, Catchpole CK. Song and brain development in canaries raised under different conditions of acoustic and social isolation over two years. Dev Neurobiol 2007; 67:1478-87. [PMID: 17525993 DOI: 10.1002/dneu.20521] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Early isolation experiments indicate that male songbirds learn their songs during an early sensitive period, although later work has shown that some open-ended learners modify songs in later years. Recent isolation experiments suggest that in some species song has a stronger genetic basis than previously thought. This study raised domestic canaries under different combinations of acoustic and social isolation and followed song development into the second year. Males raised alone in acoustic isolation developed songs with normal syllables, but larger repertoires and also produced syllables with lower repetition rates when compared to controls. The smallest repertoire occurred in males raised in a peer group. Isolate males had a smaller song control nucleus HVC than controls, but there was no effect on nucleus RA or on brain weight in general. In the second year, after introduction into a large normal colony, isolate and peer group males adjusted their syllable repertoire to normal size. In particular, the isolates reduced their repertoire even though the size of HVC showed a significant increase in volume. However, songs of isolate and peer group males still differ in repetition rate and number of single syllables in the common aviary. In contrast, control males showed low syllable turnover and no significant change in repertoire size. Nor did they show any significant change in the volumes of song control nuclei. It seems that complete isolation affects only some aspects of song and brain development, and later socialization corrects some but not all of these in the second year.
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Affiliation(s)
- Stefan Leitner
- School of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 OEX, United Kingdom.
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23
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Meaney MJ. Environmental Programming of Phenotypic Diversity in Female Reproductive Strategies. GENETICS OF SEXUAL DIFFERENTIATION AND SEXUALLY DIMORPHIC BEHAVIORS 2007; 59:173-215. [PMID: 17888799 DOI: 10.1016/s0065-2660(07)59007-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Among invertebrates, certain hermaphroditic species reproduce sexually, but with no process of sexual differentiation. In such cases the brain is bisexual: Each member of the species develops male and female sexual organs and retains the capacity to express both male and female patterns of reproductive behavior. Members of such species can reproduce socially or alone. Mammals and many other species reproduce both sexually and socially, which requires an active process of sexual differentiation of reproductive organs and brain. The primary theme of this chapter is simply that this process admits to variation and thus individual differences in gender-specific patterns of reproductive function. The focus on this chapter is the often neglected variation in the development of reproductive function in the female mammal. The basic premise is that evolution has not defined any single, optimal reproductive phenotype, but rather encourages plasticity in specific reproductive traits among same sex members of the species that are derived from variations in the quality of the prevailing environment during development that are mediated by alterations in parent-offspring interactions. Thus, the variations in parental care that define the reproductive phenotype of the offspring are influenced by the quality of the environment (i.e., nutrient availability, predation, infection, population density, and so on).
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Affiliation(s)
- Michael J Meaney
- Developmental Neuroendocrinology Laboratory, Douglas Hospital Research Centre, McGill University, Montreal, QC, Canada H4H 1R3
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24
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Scaggiante M, Grober MS, Lorenzi V, Rasotto MB. Variability of GnRH secretion in two goby species with socially controlled alternative male mating tactics. Horm Behav 2006; 50:107-17. [PMID: 16530763 DOI: 10.1016/j.yhbeh.2006.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2005] [Revised: 12/20/2005] [Accepted: 01/04/2006] [Indexed: 10/24/2022]
Abstract
Male reproductive phenotypic plasticity related to environmental-social conditions is common among teleost fish. In several species, males adopt different mating tactics depending on their size, monopolizing mates when larger, while parasitizing dominant male spawns when smaller. Males performing alternative mating tactics are often characterized by a strong dimorphism in both primary and secondary reproductive traits. According to studies on sex-changing species and on species where only one male morph is reproductively active, male alternative phenotypes are expected to vary also in gonadotropin-releasing hormone (GnRH) neurons in forebrain preoptic area (POA). Here, we compared the intra- and inter-sexual variations in number and size of GnRH neurons, along with gonads and male accessory structure investment, in two goby species, the grass goby, Zosterisessor ophiocephalus, and the black goby, Gobius niger, characterized by male alternative mating phenotypes. In both species, older and larger males defend nests, court and perform parental care, while younger and smaller ones try to sneak territorial male spawning. We found that grass goby and black goby have different patterns of GnRH expression. Grass goby presents a clear intra-sexual dimorphism in GnRH expression, related to the occurrence of alternative mating tactics, while in the black goby, only inter-sexual differences are observed. The inter- and intra-specific variability in the GnRH neurons in these two goby species is discussed in light of the differences in migratory behavior, nest type, and mating system.
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Affiliation(s)
- Marta Scaggiante
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131 Padova, Italy
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25
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Lauer LE, McCarthy MM, Mong J, Kane AS. Sex differences in neuronal morphology in the killifish hypothalamus. Brain Res 2006; 1070:145-9. [PMID: 16430871 DOI: 10.1016/j.brainres.2005.11.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2005] [Revised: 10/31/2005] [Accepted: 11/02/2005] [Indexed: 10/25/2022]
Abstract
This study examined the neuroarchitecture of the male and female killifish (Fundulus heteroclitus) hypothalamus to evaluate whether sexual dimorphism of this brain region exists in fishes as it does in mammals and other vertebrates. The rostral medulla, a brain region distinct from the hypothalamic-pituitary-gonadal axis, was also examined to determine if any observed differences were region-specific. With the use of Golgi-Cox impregnation, five dendritic characteristics were measured from neurons of both the hypothalamus and medulla including: spine density, number of branch points, dendrite length, surface area and volume. Dendritic spines are associated with excitatory synapses, and changes in density are associated with a variety of normal and pathological changes. Consistent with mammalian studies, we found that adult female killifish have 25% greater dendritic spine densities in the hypothalamus than male killifish (densities of 0.34+/-0.06 microm-1 and 0.25+/-0.08 microm-1, respectively). By contrast, no statistically significant difference between males and females was detected in spine densities in the rostral medulla. This finding supports the conclusion that hypothalamic sexual dimorphism is conserved in killifish.
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Affiliation(s)
- Lisa E Lauer
- Aquatic Pathobiology Center, Virginia-Maryland Regional College of Veterinary Medicine, College Park, MD 20742, USA
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26
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Mazzoldi C, Petersen CW, Rasotto MB. The influence of mating system on seminal vesicle variability among gobies (Teleostei, Gobiidae). J ZOOL SYST EVOL RES 2005. [DOI: 10.1111/j.1439-0469.2005.00331.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Bass AH, Zakon HH. Sonic and electric fish: at the crossroads of neuroethology and behavioral neuroendocrinology. Horm Behav 2005; 48:360-72. [PMID: 16005002 DOI: 10.1016/j.yhbeh.2005.05.022] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2005] [Revised: 05/23/2005] [Accepted: 05/31/2005] [Indexed: 10/25/2022]
Abstract
Field and laboratory studies of weakly electric and sound-producing teleost fishes demonstrate how steroidal and non-steroidal hormones mediate the translation of neural events into behavior. The development of this research program has depended upon an interdisciplinary neuroethological approach that has characterized the neurophysiological properties of the motor and sensory pathways that lead to the production and detection of easily quantified highly stereotyped behaviors, namely, electric organ discharges (EODs) and vocalizations. Neuroethological studies of these teleosts have now integrated a behavioral neuroendocrinology approach that has provided several examples of how hormone-sensitive neurobiological traits contribute to adaptive behavioral plasticity in natural habitats. As such, these studies provide guideposts for comparable studies in other groups of teleosts and vertebrates in general.
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Affiliation(s)
- Andrew H Bass
- Department of Neurobiology and Behavior, Seeley G. Mudd Hall, Cornell University, Ithaca, NY 14853, USA.
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28
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Cameron NM, Champagne FA, Parent C, Fish EW, Ozaki-Kuroda K, Meaney MJ. The programming of individual differences in defensive responses and reproductive strategies in the rat through variations in maternal care. Neurosci Biobehav Rev 2005; 29:843-65. [PMID: 15893378 DOI: 10.1016/j.neubiorev.2005.03.022] [Citation(s) in RCA: 182] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
There are profound maternal effects on individual differences in defensive responses and reproductive strategies in species ranging literally from plants to insects to birds. Maternal effects commonly reflect the quality of the environment and are most likely mediated by the quality of the maternal provision (egg, propagule, etc.), which in turn determines growth rates and adult phenotype. In this paper, we review data from the rat that suggest comparable forms of maternal effects on both defensive responses to threat and reproductive behavior and which are mediated by variations in maternal behavior. Ultimately, we will need to contend with the reality that neural development, function and health are defined by social and economic influences.
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Affiliation(s)
- Nicole M Cameron
- McGill Program for the Study of Behavior, Genes and Environment, Department of Psychiatry, Douglas Hospital Research Centre, McGill University, 6875 Boulevard LaSalle, Montréal, Que., Canada H4H 1R3
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29
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Scaggiante M, Grober MS, Lorenzi V, Rasotto MB. Changes along the male reproductive axis in response to social context in a gonochoristic gobiid, Zosterisessor ophiocephalus (Teleostei, Gobiidae), with alternative mating tactics. Horm Behav 2004; 46:607-17. [PMID: 15555503 DOI: 10.1016/j.yhbeh.2004.06.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Revised: 06/20/2004] [Accepted: 06/22/2004] [Indexed: 11/17/2022]
Abstract
Sexual selection has given rise, in several taxa, to intrasexual variation in male phenotype. While evolutionary studies have provided explanations of the adaptive function of this dramatic male phenotypic diversity, the proximate control of its expression has still to be completely understood. Several observations, primarily from sex-changing species, indicated a major role of social interactions in reproductive axis regulation and consequently in the expression of alternative male phenotypes. Here we documented changes along the male reproductive axis in response to social context in a gonochoristic species, the grass goby Zosterisessor ophiocephalus, where fully functional alternative male mating tactics appear to be expressed as an ontogenetic gradient. In the grass goby, larger and older males dig a nest and perform parental care, while smaller males sneak fertilization during territorial male spawning. Territorial males are characterized by a higher number of gonadotropin-releasing hormone (GnRH) neurons in forebrain preoptic area, smaller testes, larger seminal vesicles, and viscous ejaculates that last longer and contain fewer sperm than those of sneakers. To experimentally investigate the role of social factors in inducing changes along the male reproductive axis, sneakers were tested in two different situations: nesting alone or with ripe females. Sneakers that mated and performed parental care showed dramatic changes in brain, reproductive apparatus morphology, and ejaculate traits. GnRH-immunoreactive cells in forebrain preoptic area increased in number, reaching values typical of wild-caught parental males. Testes size decreased while seminal vesicle size increased and ejaculates showed lower sperm densities. These results were discussed within the framework of the social transduction hypothesis, which predicts that social experience should mediate, through a cascade of internal processes, shifts between morphs throughout life.
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Affiliation(s)
- Marta Scaggiante
- Department of Biology, University of Padova, 35131 Padova, Italy
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30
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Veney SL, Wade J. Steroid receptors in the adult zebra finch syrinx: a sex difference in androgen receptor mRNA, minimal expression of estrogen receptor alpha and aromatase. Gen Comp Endocrinol 2004; 136:192-9. [PMID: 15028522 DOI: 10.1016/j.ygcen.2003.12.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2003] [Revised: 12/18/2003] [Accepted: 12/23/2003] [Indexed: 11/19/2022]
Abstract
The zebra finch syrinx (sound production organ) is a sexually dimorphic component of the song system. Only male zebra finches sing, and in parallel, the overall mass and size of fibers in the two largest syrinx muscles are greater in males than females. Despite these obvious sexual dimorphisms, little is known about the role of steroid hormones in the maintenance of the structure and/or function of the syrinx. In this report, we used in situ hybridization to assess the expression of androgen receptor (AR), estrogen receptor alpha (ERalpha), and aromatase (AROM) mRNAs in the syrinx of adult male and female zebra finches. Increased AR mRNA expression was noted in males compared to females in two regions, over the ventralis muscle and in a band of connective tissue neighboring cartilage (perichondria). In contrast, we did not detect specific ERalpha or AROM mRNA expression within the syrinx. However, substantial ERalpha mRNA was present in oviduct, and aromatase mRNA was expressed at high levels in ovary. In parallel, an assay for AROM detected activity in ovary, but not in syrinx tissue from males or females. Taken together, these data suggest that the adult syrinx is sensitive to androgens; that sex differences in function and morphology of the syrinx may in part be due to increased expression of AR in males compared to females. In contrast, estrogen receptor alpha and AROM appear to have limited roles.
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Affiliation(s)
- Sean L Veney
- Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA.
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31
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Weltzien FA, Andersson E, Andersen Ø, Shalchian-Tabrizi K, Norberg B. The brain–pituitary–gonad axis in male teleosts, with special emphasis on flatfish (Pleuronectiformes). Comp Biochem Physiol A Mol Integr Physiol 2004; 137:447-77. [PMID: 15123185 DOI: 10.1016/j.cbpb.2003.11.007] [Citation(s) in RCA: 209] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2003] [Revised: 11/05/2003] [Accepted: 11/06/2003] [Indexed: 02/03/2023]
Abstract
The key component regulating vertebrate puberty and sexual maturation is the endocrine system primarily effectuated along the brain-pituitary-gonad (BPG) axis. By far most investigations on the teleost BPG axis have been performed on salmonids, carps, catfish and eels. Accordingly, earlier reviews on the BPG axis in teleosts have focused on these species, and mainly on females (e.g. 'Fish Physiology, vol. IXA. Reproduction (1983) pp. 97'; 'Proceedings of the Fourth International Symposium on the Reproductive Physiology of Fish. FishSymp91, Sheffield, UK, 1991, pp. 2'; 'Curr. Top. Dev. Biol. 30 (1995) pp. 103'; 'Rev. Fish Biol. Fish. 7 (1997) pp. 173'; 'Proceedings of the Sixth International Symposium on the Reproductive Physiology of Fish. John Grieg A/S, Bergen, Norway, 2000, pp. 211'). However, in recent years new data have emerged on the BPG axis in flatfish, especially at the level of the brain and pituitary. The evolutionarily advanced flatfishes are important model species both from an evolutionary point of view and also because many are candidates for aquaculture. The scope of this paper is to review the present status on the male teleost BPG axis, with an emphasis on flatfish. In doing so, we will first discuss the present understanding of the individual constituents of the axis in the best studied teleost models, and thereafter discuss available data on flatfish. Of the three constituents of the BPG axis, we will focus especially on the pituitary and gonadotropins. In addition to reviewing recent information on flatfish, we present some entirely new information on the phylogeny and molecular structure of teleost gonadotropins.
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Affiliation(s)
- Finn-Arne Weltzien
- Institute of Marine Research, Austevoll Aquaculture Research Station, 5392 Storebø, Norway.
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32
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Abstract
Sound communication is not unique to humans but rather is a trait shared with most non-mammalian vertebrates. A practical way to address questions of vocal signal encoding has been to identify mechanisms in non-mammalian model systems that use acoustic communication signals in their social behavior. Teleost fishes, the largest group of living vertebrates, include both vocal and non-vocal species that exploit a wide range of acoustic niches. Here, we focus on those vocal species where combined behavioral and neurobiological studies have recently begun to elucidate a suite of adaptations for both the production and the perception of acoustic signals essential to their reproductive success and survival. Studies of these model systems show that teleost fish have the vocal-acoustic behaviors and neural systems both necessary and sufficient to solve acoustic problems common to all vertebrates. In particular, behavioral studies demonstrate that temporal features within a call, including pulse duration, rate and number, can all be important to a call's communicative value. Neurobiological studies have begun to show how these features are produced by a vocal motor system extending from forebrain to hindbrain levels and are encoded by peripheral and central auditory neurons. The abundance and variety of vocal fish present unique opportunities for parallel investigations of neural encoding, perception, and communication across a diversity of natural, acoustic habitats. As such, investigations in teleosts contribute to our delineating the evolution of the vocal and auditory systems of both non-mammalian and mammalian species, including humans.
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Affiliation(s)
- Andrew H Bass
- Department of Neurobiology and Behavior, Cornell University, Seeley G. Mudd Hall, Ithaca, NY 14853, USA.
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Abstract
Intrasexual variation in reproductive behaviour, morphology and physiology is taxonomically widespread in vertebrates, and is as biologically and ecologically significant as the differences between the sexes. In this review, we examine the diverse patterns of intrasexual variation in reproductive behaviours within vertebrates. By illustrating the genetic, cellular, hormonal and/or neural mechanisms underlying behavioural variation in a number of species, another level of complexity is added to studies of brain organization and function. Such information increases our understanding of the unique and conserved mechanisms underlying sex and individual differences in behaviour in vertebrates as a whole. Here, we show that intrasexual variation in behaviour may be discrete or continuous in nature. Moreover, this variation may be due to polymorphism at a single genetic locus or many loci, or may even be the result of phenotypic plasticity. Phenotypic plasticity simply refers to cases where a single genotype (or individual) can produce (or display) different phenotypes. Defined in this way, plasticity subsumes many different types of behavioural variation. For example, some behavioural phenotypes are established by environmental factors during early ontogeny, others are the result of developmental transitions from one phenotype early in life to another later in life, and still other strategies are facultative with different behaviours displayed in different social contexts.
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Affiliation(s)
- T Rhen
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, NC 27709, USA.
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Anatomical distribution and cellular basis for high levels of aromatase activity in the brain of teleost fish: aromatase enzyme and mRNA expression identify glia as source. J Neurosci 2001. [PMID: 11698605 DOI: 10.1523/jneurosci.21-22-08943.2001] [Citation(s) in RCA: 233] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although teleost fish have higher levels of brain aromatase activity than any other vertebrate group, its function remains speculative, and no study has identified its cellular basis. A previous study determined aromatase activity in a vocal fish, the plainfin midshipman (Porichthys notatus), and found highest levels in the telencephalon and lower levels in the sonic hindbrain, which was dimorphic between and within (males) sexes. We have now localized aromatase-containing cells in the midshipman brain both by immunocytochemistry using teleost-specific aromatase antibodies and by in situ hybridization using midshipman-specific aromatase probes. Aromatase-immuno-reactivity and mRNA hybridization signal are consistent with relative levels of aromatase activity in different brain regions: concentrated in the dimorphic sonic motor nucleus, in a band just beneath the periaqueductal gray in the midbrain, in ventricular regions in the hypothalamus, and highest levels in the telencephalon especially in preoptic and ventricular areas. Surprisingly, double-label immunofluorescence does not show aromatase-immunoreactive colocalization in neurons, but instead in radial glia throughout the brain. This is the first study to identify aromatase expression mostly, if not entirely, in glial cells under normal rather than brain injury-dependent conditions. The abundance of aromatase in teleosts may represent an adaptation linked to continual neurogenesis that is known to occur throughout an individual's lifetime among fishes. The localization of aromatase within the intersexually and intrasexually dimorphic vocal-motor circuit further implies a function in the expression of alternative male reproductive phenotypes and, more generally, the development of natural, individual variation of specific brain nuclei.
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Bass AH, Bodnar DA, Marchaterre MA. Acoustic nuclei in the medulla and midbrain of the vocalizing Gulf toadfish (Opsanus beta). BRAIN, BEHAVIOR AND EVOLUTION 2001; 57:63-79. [PMID: 11435667 DOI: 10.1159/000047226] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The organization of the descending and secondary octaval nuclei in the hindbrain of the Gulf toadfish, Opsanus beta, was revealed following the injection of biotin compounds into a physiologically identified auditory region of the torus semicircularis. The results show retrogradely-filled neurons mainly in a dorsomedial division of the descending octaval nucleus, and dorsal and ventral divisions of a secondary octaval nucleus; minor labeling also appeared in dorsolateral and rostromedial intermediate divisions of the descending nucleus. The pattern identified is consistent with that reported in other teleosts, including both vocal and non-vocal species, and clarifies earlier reports of the organization of hindbrain octaval nuclei in toadfish and the closely related midshipman fish.
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Affiliation(s)
- A H Bass
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, USA.
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Brockmann HJ. The evolution of alternative strategies and tactics. ADVANCES IN THE STUDY OF BEHAVIOR 2001. [DOI: 10.1016/s0065-3454(01)80004-8] [Citation(s) in RCA: 193] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Abstract
Arginine vasotocin (AVT) and its mammalian homologue arginine vasopressin (AVP) modulate reproduction-related and other social behaviors in a broad range of vertebrate species. These functions of AVT/AVP may be in part achieved through the modulation of sensorimotor integration, although experimental evidence supporting this hypothesis remains limited. In the present experiments, we demonstrate (1) AVT innervation of candidate vocal-acoustic brain regions, and (2) AVT modulation of vocal-motor physiology in the plainfin midshipman fish (Porichthys notatus), which uses vocalizations in both mate attraction and agonistic contexts. AVT distribution was compared with known vocally active brain regions and to central auditory and vocal pathways. AVT-immunoreactive fibers and putative terminals descend almost exclusively from the preoptic area and are found in two primary candidate sites for vocal-acoustic integration - the anterior tuberal hypothalamus and paralemniscal midbrain tegmentum. AVT immunoreactivity is also located in several other vocally active regions, including the ventral tuberal nucleus, periaqueductal gray, and paraventricular regions of the isthmus and rostral hindbrain. The parvocellular preoptic area itself is also vocally active, although thresholds are substantially higher than for other regions. The functional significance of AVT input to vocal-acoustic regions was demonstrated in the paralemniscal midbrain where local delivery of AVT modulated electrically evoked, rhythmic vocal-motor output, which precisely mimicked natural vocalizations. AVT produced dose-dependent inhibitions of parameters associated with call initiation (burst latency and number of vocal-motor bursts elicited) but not of vocal-motor patterning (fundamental frequency and burst duration). Together, these findings provide support for the proposal that AVT modulates sensorimotor processes underlying social/acoustic communication.
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Affiliation(s)
- J L Goodson
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853, USA
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DOS SANTOS MANUELE, MODESTO TERESA, MATOS RICARDOJ, GROBER MATTHEWS, OLIVEIRA RUIF, CANÁRIO ADELINO. SOUND PRODUCTION BY THE LUSITANIAN TOAD FISH,HALOBATRACHUS DIDACTYLUS. BIOACOUSTICS 2000. [DOI: 10.1080/09524622.2000.9753440] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
Alternative reproductive tactics within one sex, adult sex or role change, and reproductive suppression are all forms of reproductive plasticity commonly exhibited among teleost fishes. The two neuropeptides that have been most extensively studied with regard to such behavioral plasticity are gonadotropin releasing hormone (GnRH) and arginine vasotocin (AVT). Here, we review intra- and intersexual variation in the number and size of GnRH and AVT neurons along with gonadal phenotype in those species of teleosts showing intraspecific plasticity in reproductive behavior. In several species, male dimorphisms in the number and/or size of GnRH neurons in the forebrain's preoptic area parallel a divergence in relative gonad size and reproductive tactics. The available studies of AVT-containing neurons in the preoptic area also indicate intrasexual dimorphisms among males, although a proximate link to other reproductive traits and behavioral outcomes is more difficult to recognize. For both GnRH and AVT, there are also species-typical patterns in the coupling between structural (e.g., neuronal and gonadal) traits and reproductive tactic expressed, which likely reflect distinct patterns of adaptation to particular ecological environments. As discussed, neurophysiological, biochemical, and receptor density studies are now essential to establish the functional significance of the diverse organizational patterns of GnRH and AVT neurons in teleosts. Similar studies also need to be carried out in species of other vertebrate groups that show comparable behavioral plasticity.
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Affiliation(s)
- C M Foran
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853, USA
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Knapp R, Marchaterre MA, Bass AH. Early development of the motor and premotor circuitry of a sexually dimorphic vocal pathway in a teleost fish. JOURNAL OF NEUROBIOLOGY 1999; 38:475-90. [PMID: 10084683 DOI: 10.1002/(sici)1097-4695(199903)38:4<475::aid-neu4>3.0.co;2-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The plainfin midshipman fish (Porichthys notatus) has a caudal hindbrain vocal motor circuit that has been proposed to share a common embryonic origin with the hindbrain vocal networks of other vertebrates. In midshipman, this vocal circuit includes three groups of neurons: sonic motor, pacemaker, and ventral medullary. Here, transneuronal transport of biocytin or neurobiotin was used to delineate the early ontogeny of the three hindbrain vocal nuclei and their pattern of connectivity. The organization of the vocal nuclei was studied in animals beginning soon after hatching until the nuclei have the adult phenotype at the time fish become free-swimming. There is a clear sequence of events whereby motoneurons establish their connections with the sonic muscle prior to establishing connections with premotor neurons; developmental milestones of the vocal pathway parallel those of the sonic muscle. The results also indicate that sexual differentiation of the vocal motor system in midshipman begins early in development, well before any evidence of sexual maturation. Embryonic males and females differ in the relationship between soma size and body length for the three hindbrain nuclei. Males are also more variable than females in body mass, volume of the sonic motor nucleus, and motoneuron cell size.
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Affiliation(s)
- R Knapp
- Section of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853, USA
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Aromatase activity in hindbrain vocal control region of a teleost fish: divergence amoung males with alternative reproductive tactics. Proc Biol Sci 1999; 266:131-136. [PMCID: PMC1689660 DOI: 10.1098/rspb.1999.0612] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023] Open
Abstract
Type I male midshipman fish acoustically court females, whereas type II males do not but instead sneak or satellite spawn to compete with type I males for fertilizations. 'Singing' type I males diverge from type II males and females in the organization of an expansive hindbrain pacemaker–motoneuron circuit that establishes the physical attributes of vocalizations. Here, levels of aromatase activity were determined in homogenates of brain by measuring the conversion of 3H-androstenedione (AE) to 3H-oestrone (E1) and 3H-oestradiol (E2). Levels were highest in the telencephalon–preoptic area and similar for all morphs. Lower levels were in a region including the diencephalon, midbrain and cerebellum, although levels were significantly higher in females compared with type I males. In the vocal hindbrain region, aromatase levels were three- to five-fold higher in type II males and females than in type I males, and in castrated type II males than in castrated type I males. Conversion of testosterone to oestrogen in type II males and females may effectively prevent testosterone-induced maturation of the vocal system that characterizes type I males. Aromatase may thus be a key enzyme regulating the expression of individual-specific brain circuitry and behaviours among members of one sex.
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Herfeld S, Moller P. Effects of 17alpha-methyltestosterone on sexually dimorphic characters in the weakly discharging electric fish, Brienomyrus niger (Günther, 1866) (Mormyridae): electric organ discharge, ventral body wall indentation, and anal-Fin ray bone expansion. Horm Behav 1998; 34:303-19. [PMID: 9878279 DOI: 10.1006/hbeh.1998.1486] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adult males of African weakly discharging electric fish (family: Mormyridae) are distinguished from juveniles and adult females by a dorsally directed indentation of the posterior ventral body wall and by massive bone expansion of the bases of a select number of anal-fin rays. These sexually dimorphic structures seem to facilitate the anal-fin reflex that is displayed during courtship when the male envelopes its anal fin around the female's to form a common spawning pouch. Expanded bone could provide additional surface for muscle attachment and thus assist in part with the courtship sequence. Based on the fact that the expression of the male sexually dimorphic electric organ discharge (EOD) is under androgen control, and that the female EOD can be masculinized through testosterone administration, we hypothesized that androgens should also drive anal-fin ray bone expansion in male mormyrids and equally effect male-like changes in treated juveniles and adult females. Exogenous androgen treatment (17alpha-methyltestosterone) of adult female Brienomyrus niger resulted in a male-like EOD, and male-typical structural transformations (body wall indentation and anal-fin ray bone expansion). Some of these changes were immediate and receded following hormone withdrawal (EOD), while others developed more slowly and were apparently permanent (indentation and bone formation). 17alpha-Methyltestosterone administration affected only those targets in females that are normally involved in the male's reproductive behavior, i.e., its courtship signal (EOD) and two morphological features (body-wall indentation and bone expansion). Rays of the dorsal or caudal fins were never affected.
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Affiliation(s)
- S Herfeld
- Department of Psychology, Hunter College of the City University of New York, New York, New York, 10024-5192, USA
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44
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McKibben JR, Bass AH. Behavioral assessment of acoustic parameters relevant to signal recognition and preference in a vocal fish. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 1998; 104:3520-3533. [PMID: 9857511 DOI: 10.1121/1.423938] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Acoustic signal recognition depends on the receiver's processing of the physical attributes of a sound. This study takes advantage of the simple communication sounds produced by plainfin midshipman fish to examine effects of signal variation on call recognition and preference. Nesting male midshipman generate both long duration (> 1 min) sinusoidal-like "hums" and short duration "grunts." The hums of neighboring males often overlap, creating beat waveforms. Presentation of humlike, single tone stimuli, but not grunts or noise, elicited robust attraction (phonotaxis) by gravid females. In two-choice tests, females differentiated and chose between acoustic signals that differed in duration, frequency, amplitude, and fine temporal content. Frequency preferences were temperature dependent, in accord with the known temperature dependence of hum fundamental frequency. Concurrent hums were simulated with two-tone beat stimuli, either presented from a single speaker or produced more naturally by interference between adjacent sources. Whereas certain single-source beats reduced stimulus attractiveness, beats which resolved into unmodulated tones at their sources did not affect preference. These results demonstrate that phonotactic assessment of stimulus relevance can be applied in a teleost fish, and that multiple signal parameters can affect receiver response in a vertebrate with relatively simple communication signals.
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Affiliation(s)
- J R McKibben
- Section of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853, USA.
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45
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Foran CM, Bass AH. Preoptic AVT immunoreactive neurons of a teleost fish with alternative reproductive tactics. Gen Comp Endocrinol 1998; 111:271-82. [PMID: 9707473 DOI: 10.1006/gcen.1998.7113] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent reports have implicated an important role for arginine vasotocin (AVT) in the socially mediated sexual differentiation of fishes. This study focuses on the plainfin midshipman (Porichthys notatus) which exhibits two male morphs, type I and type II, differing in a suite of behavioral, neurobiological, and endocrine traits. Immunocytochemical techniques were used to detect neurons containing AVT-like peptide in the forebrain of juveniles, adult females, and type I and type II males. AVT immunoreactive (ir) somata were localized to three regions: the terminal nerve ganglion, the preoptic area (POA), and the pineal stalk. The profile area, or size, of AVT-ir POA neurons differed across the four classes of midshipman and was strongly correlated to differences in body size among the groups. By contrast, the number of AVT-ir cells in the POA exhibited no difference across the classes of midshipman. The number of POA cells containing AVT is therefore likely to be set early in development and not to change with the growth of the animal. An analysis of AVT-ir cell number normalized by body mass revealed that the larger morphs, type I males and females, have fewer cells per gram body mass than type II males and juveniles. Therefore, type II males have a juvenile-like AVT POA phenotype with smaller cells and more numerous cells per unit body mass than type I males. Type II males also exhibit more variability in the number of AVT-ir cells found in the POA compared to type I males.
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Affiliation(s)
- C M Foran
- Section of Neurobiology and Behavior, Cornell University, Ithaca, New York, 14853, USA
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Abstract
1. The study of sex differences in the brain and behavior of reptiles presents an excellent opportunity both to discern general principles of sexual differentiation in the nervous system and to explore the evolutionary history of this process in amniote vertebrates. 2. Findings in several reptiles suggest that some sex differences found in mammals and birds are conserved while others are not. Conserved features include areas in the limbic forebrain involved in the regulation of social and sexual behaviors. As in mammals and birds, it is rare to find differences in the distribution of sex steroid concentrating neurons in reptiles but common to find differences in the distribution of the various steroid hormone receptors and in their regulation. 3. This research has revealed that differences in social and sexual behavior are reflected better by the activity, not by the size, of hormone-sensitive limbic areas. 4. Finally, species differences in plasma levels of sex hormones are paralleled by differences in behavioral sensitivity to these hormones as well as by differences in the regulation of genes coding for steroid hormone receptors.
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Affiliation(s)
- J Godwin
- Department of Zoology, University of Texas at Austin 78712, USA
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Abstract
Many aspects of reproductive physiology are subject to regulation by social interactions. These include changes in neural and physiological substrates of reproduction. How can social behavior produce such changes? In experiments reported here, we manipulated the social settings of teleost fish and measured the effect (1) on stress response as reflected in cortisol production, (2) on reproductive potential as measured in production of the signaling peptide, gonadotropin-releasing hormone, and (3) on reproductive function measured in gonad size. Our results reveal that the level of the stress hormone cortisol depends critically on both the social and reproductive status of an individual fish and on the stability of its social situation. Moreover, the reproductive capacity of an individual fish depends on these same variables. These results show that social encounters within particular social contexts have a profound effect on the stress levels as well as on reproductive competence. Social behavior may lead to changes in reproductive state through integration of cortisol changes in time. Thus, information available from the stress pathway may provide socially relevant signals to produce neural change.
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Abstract
One of the first things that we are impressed by is the great variety of animals, particularly their behaviors and their physiologies. With so many differences, are there any generalities? With the establishment of evolutionary theory, evidence of "unity in diversity" comes with discoveries of common anatomical features, the cell cycle, conservation of intermediary metabolism, and the genetic code, to name but a few. In vertebrates there appears to be a conservation of the neural circuits underlying sexual behavior, but it is still too early to state the extent to which this concept can be extended to the hormonal mechanisms underlying behavior. Much of our conceptual understanding of behavioral neuroendocrinology stems from extensive studies on relatively few species. When an evolutionary perspective is applied to behavioral neuroscience, the breadth and validity of our assumptions about the mechanisms that control species-typical behaviors are challenged. This is not the same thing as saying that there are few unitary explanations that apply to all mammals, amniotes, or even vertebrates. Considerable information has been gathered about the neuroendocrine bases of behavior in a few species, but to uncover truly broad generalizations, we must look with equal intensity and rigor at other organisms. The pattern of evolution is best illustrated in the diversity of organisms, and the ecological and evolutionary perspective illuminates the utility of various "experiments of nature." By studying (1) closely related species that live in different habitats, we can see if the adaptational responses are similar, and (2) distantly related species that live in the same habitat, we can see if the solutions are analogous. The unique qualities of each species also give us a deeper understanding of the constraints in fundamental processes. When basic conflicts exist, control mechanisms adapt or the species goes extinct. Interestingly, although the neural circuits themselves do not degenerate, they are either no longer used or coopted for other functions.
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Affiliation(s)
- D Crews
- Department of Zoology, University of Texas at Austin 78712, USA.
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Hrdy SB, Rodman P, Charnov EL, Seger J, Hawkes K, Emlen ST, Foster SA, Gowaty PA, Haig D, Hauser M, Jacobs LF, Smuts BB. Sociobiology's Successes. Science 1996; 274:162-3. [PMID: 17847218 DOI: 10.1126/science.274.5285.162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Bass AH, Horvath BJ, Brothers EB. Nonsequential developmental trajectories lead to dimorphic vocal circuitry for males with alternative reproductive tactics. JOURNAL OF NEUROBIOLOGY 1996; 30:493-504. [PMID: 8844513 DOI: 10.1002/(sici)1097-4695(199608)30:4<493::aid-neu5>3.0.co;2-z] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Midshipman fish, Porichthys notatus, have two male reproductive morphs: type 1 males generate long duration advertisement calls ("hums") to attract females to a nest; type II males sneak-spawn and, like females, do not produce mate calls but generate short duration agonistic calls. A vocal pacemaker circuit includes: motoneurons in the caudal brain stem and rostral spinal cord that innervate vocal/sonic muscles; pacemaker neurons that are located ventrolateral to motoneurons and establish their fundamental discharge frequency; and a ventral medullary nucleus that couples the motoneuron-pacemaker circuit bilaterally. Transneuronal biocytin transport identified morph-specific developmental trajectories for the vocal circuit. Among nonreproductive, juvenile type I males, motoneuron soma size and motor nucleus volume increase most during a stage prior to sexual maturation. An additional increase in motoneuron size and nucleus volume is coupled to the greatest increase in pacemaker soma size at a stage coincident with the onset of sexual maturity; ventral medullary neurons show similar growth increments during both stages. Type II males (and females) mature with no or little change in cell size or motor nucleus volume. The results indicate that alternative mating tactics are paralleled by alternative developmental trajectories for the neurons that determine tactic-specific behaviors, in this case vocalizations. Together with aging data based on otolith growth, the results support the hypothesis that alternative male morphs in midshipman fish adopt nonsequential, mutually exclusive life history tactics.
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Affiliation(s)
- A H Bass
- Section of Neurobiology and Behavior, Cornell University, Ithaca, New York 14853-6401, USA.
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