Aggression is a common behavioral trait shared in many animals, including both vertebrates and invertebrates. However, the type and intensity of agonistic encounters and displays can vary widely both across and within...Aggression is a common behavioral trait shared in many animals, including both vertebrates and invertebrates. However, the type and intensity of agonistic encounters and displays can vary widely both across and within species, resulting in complicated or subjective interpretations that create difficulties in developing theoretical models that can be widely applied. The need to easily and objectively identify quantifiable behaviors and their associated morphologies becomes especially important when attempting to decipher the neurological mechanisms underlying this complex behavior. Monoamines, neuropeptides, and pheromones have been implicated as important neuromodulators for agonistic displays in both invertebrates and vertebrates. Ad- ditionally, recent breakthroughs in insect research have revealed exciting proximate mechanisms important in aggression that may be broadly relevant, due to the relatively high conservation of these neurochemical systems across animal taxa. In this review, we present the latest research demonstrating the importance of monoamines, neuropeptides, and pheromones as neuromodulators for aggression across a variety of insect species. Additionally, we describe the stalk-eyed fly as a model system for studying aggres- sion, which integrates physiological, morphological, and neurochemical approaches in exploring detailed mechanisms responsible for this common yet complex behavior. We conclude with our perspective on the most promising lines of future research aimed at understanding the proximate and ultimate mechanisms underlying aggressive behaviors .展开更多
Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual sele...Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual selection occurs when evolution in traits and preferences within populations causes differentiation among populations, such that females in alternative populations prefer sexual signals of their own population relative to others. Differentiated traits and preferences thereby play an active role in limiting gene flow between divergent populations. The effectiveness of differentiated preferences in maintaining differentiated male signals against the homogenizing effects of gene flow across populations will be limited by both the degree to which fe- males can discriminate against non-local males, and the breeding values of traits and preferences. Populations of the Hawaiian cricket Laupala cerasina have diverged in pulse rate, a sexually selected male signal, and female acoustic preference for pulse rate. Gene flow between neighboring populations may be reduced if migrants from sexually diverged populations experience re- duced mating success. We show that females discriminate among divergent songs characteristic of neighboring populations, that differences among populations in song and preference breed true in a common environment, and that mean preferences for each population closely match the mean pulse rates. Divergence in preference was observed only between populations that also dif- fered in song. Along with a striking ability to discriminate slight differences in song, correlated evolution of song and preference within populations could be a mechanism that promotes assortative mating among populations, thereby reducing gene flow, and leading to speciation in Laupala [Current Zoology 58 (3): 416-425, 2012].展开更多
Understanding the mechanisms underlying complex behaviors re- quires a comprehensive investigation of the neurobiological factors that regulate and modulate their expression. Monoamines, such as serotonin, dopamine, a...Understanding the mechanisms underlying complex behaviors re- quires a comprehensive investigation of the neurobiological factors that regulate and modulate their expression. Monoamines, such as serotonin, dopamine, and noradrenaline, serve a variety of essential physiological roles in modulating animal behavior. Furthermore, the evolutionary conservation of these aminergic systems spans across both vertebrates and invertebrates, having comparable effects in such diverse processes as learning and memory, aggression, mating behaviors and reproduction, stress responses, locomotion, and col- lective social behaviors (Dishman 1997; Libersat and Pflueger 2004; Kamhi and Traniello 2013; Bubak et al. 2014a; De Boer et al. 2015). Outstanding research is currently being conducted in this field, uncovering remarkable similarities in neural circuitries even among highly divergent taxa, such as Drosophila and humans. Investigating the neural mechanisms involved in the monoaminerglc modulation of behavior across a variety of taxonomically distant species can provide researchers with a better understanding of the origins and functions of these systems. The goal of this special issue is to provide a venue in which colleagues studying similar questions across highly divergent animal systems can present their recent and groundbreaking work in this exciting area of biology. We hope this collection of papers will encourage and stimulate a dialogue on the similarities of monoaminergic function in a wide variety of animals and ultimately promote future comparative approaches when inves- tigating behavioral modulation.展开更多
文摘Aggression is a common behavioral trait shared in many animals, including both vertebrates and invertebrates. However, the type and intensity of agonistic encounters and displays can vary widely both across and within species, resulting in complicated or subjective interpretations that create difficulties in developing theoretical models that can be widely applied. The need to easily and objectively identify quantifiable behaviors and their associated morphologies becomes especially important when attempting to decipher the neurological mechanisms underlying this complex behavior. Monoamines, neuropeptides, and pheromones have been implicated as important neuromodulators for agonistic displays in both invertebrates and vertebrates. Ad- ditionally, recent breakthroughs in insect research have revealed exciting proximate mechanisms important in aggression that may be broadly relevant, due to the relatively high conservation of these neurochemical systems across animal taxa. In this review, we present the latest research demonstrating the importance of monoamines, neuropeptides, and pheromones as neuromodulators for aggression across a variety of insect species. Additionally, we describe the stalk-eyed fly as a model system for studying aggres- sion, which integrates physiological, morphological, and neurochemical approaches in exploring detailed mechanisms responsible for this common yet complex behavior. We conclude with our perspective on the most promising lines of future research aimed at understanding the proximate and ultimate mechanisms underlying aggressive behaviors .
文摘Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual selection occurs when evolution in traits and preferences within populations causes differentiation among populations, such that females in alternative populations prefer sexual signals of their own population relative to others. Differentiated traits and preferences thereby play an active role in limiting gene flow between divergent populations. The effectiveness of differentiated preferences in maintaining differentiated male signals against the homogenizing effects of gene flow across populations will be limited by both the degree to which fe- males can discriminate against non-local males, and the breeding values of traits and preferences. Populations of the Hawaiian cricket Laupala cerasina have diverged in pulse rate, a sexually selected male signal, and female acoustic preference for pulse rate. Gene flow between neighboring populations may be reduced if migrants from sexually diverged populations experience re- duced mating success. We show that females discriminate among divergent songs characteristic of neighboring populations, that differences among populations in song and preference breed true in a common environment, and that mean preferences for each population closely match the mean pulse rates. Divergence in preference was observed only between populations that also dif- fered in song. Along with a striking ability to discriminate slight differences in song, correlated evolution of song and preference within populations could be a mechanism that promotes assortative mating among populations, thereby reducing gene flow, and leading to speciation in Laupala [Current Zoology 58 (3): 416-425, 2012].
文摘Understanding the mechanisms underlying complex behaviors re- quires a comprehensive investigation of the neurobiological factors that regulate and modulate their expression. Monoamines, such as serotonin, dopamine, and noradrenaline, serve a variety of essential physiological roles in modulating animal behavior. Furthermore, the evolutionary conservation of these aminergic systems spans across both vertebrates and invertebrates, having comparable effects in such diverse processes as learning and memory, aggression, mating behaviors and reproduction, stress responses, locomotion, and col- lective social behaviors (Dishman 1997; Libersat and Pflueger 2004; Kamhi and Traniello 2013; Bubak et al. 2014a; De Boer et al. 2015). Outstanding research is currently being conducted in this field, uncovering remarkable similarities in neural circuitries even among highly divergent taxa, such as Drosophila and humans. Investigating the neural mechanisms involved in the monoaminerglc modulation of behavior across a variety of taxonomically distant species can provide researchers with a better understanding of the origins and functions of these systems. The goal of this special issue is to provide a venue in which colleagues studying similar questions across highly divergent animal systems can present their recent and groundbreaking work in this exciting area of biology. We hope this collection of papers will encourage and stimulate a dialogue on the similarities of monoaminergic function in a wide variety of animals and ultimately promote future comparative approaches when inves- tigating behavioral modulation.