The morphological characteristics of the hind wing venation of tetrigids were analyzed on the basis of morphometric measurement, with 20 species and 18 different variables selected for this study. Results show that th...The morphological characteristics of the hind wing venation of tetrigids were analyzed on the basis of morphometric measurement, with 20 species and 18 different variables selected for this study. Results show that three principal components have a higher load at the length between the starting point of the costal vein and the tip of the fourth anal vein, between the tip of the costal vein and the tip of the third anal vein, and between the tip of the costal vein and the tip of the eleventh anal vein. There exists a contrast between wing length and width.展开更多
The ovipositor of parasitic insect is a highly specialized organ and crucial for parasitising. Morphology and structure of the ovipositor in female Macrocentrus cingulum, a polyembryonic parasitoid, are observed in SE...The ovipositor of parasitic insect is a highly specialized organ and crucial for parasitising. Morphology and structure of the ovipositor in female Macrocentrus cingulum, a polyembryonic parasitoid, are observed in SEM studies. The ovipositor of M. cingulum consists of the valvulae 1, 2 and 3. The valvulae 1 and 2 of ovipositor house in the valvulae 3 at rest and the valvulae 1 and 2 part from the valvulae 3 at probing and ovipositing. The cross-section of valvulae 3 shows that the valvulae 3 is hollow which may reduce the weight of ovipositor and make the ovipositor more flexible. The distal end of stylus (valvulae l, 2) becomes extremely sharp and the piercing tip of valvulae 1 and 2 form the arrangement of tongue-and-groove. This arrangement may support valvulae 2 slide longitudinally along the valvulae 1. Numbers of pores are distributed on the cuticle of the valvulae l and 2. The piecing tip of valvulae 1 and 2 have more pores than proximal and intermediate region. The out side of valvulae 3 is completely covered with chactica sensilla and the distal end of valvulae 3 has more sensilla than proximal and intermediate region. The function and structure of ovipositor of M. cingulum was discussed and compared with other species.展开更多
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
The study of speciation genetics is primarily concerned with identifying the genetic traits that allow divergent selec- tion to overcome the homogenizing effects of gene flow. Felsenstein reviewed this race between ge...The study of speciation genetics is primarily concerned with identifying the genetic traits that allow divergent selec- tion to overcome the homogenizing effects of gene flow. Felsenstein reviewed this race between gene flow and selection, con- cluding that speciation with gene flow was unlikely under a "two-allele model" (where two traits were necessary for reproductive isolation) but that divergence could occur quite easily under a "one-allele model." Despite this finding, much of the sympatric speciation research involving phytophagous insects has relied on a two-trait model, where insects evolve both preferences for and increased performance on novel host plants. Philopatry (a tendency to remain where one was born) is known to occur in phyto- phagous insects and is a single trait isolation mechanism. However, it is traditionally invoked as simply augmenting reproductive isolation. Species in the Enchenopa binotata complex are believed to have speciated in sympatry. They exhibit host plant prefe- rences, host specific performance advantages and strong philopatry. We experimentally shifted E. binotata to evolutionarily novel host plants. Previous research has demonstrated that the experimental population of insects possesses genetic variation in prefe- rence and performance to the novel host. The degree of philopatry at mating and egg-laying was assayed for the first four years under full choice conditions. Host plant preference and performance was assayed after eight years. Philopatry was an immediate and strong isolating mechanism, while preference for and performance on the novel host lagged. We therefore suggest that philo- patry may be a more important mechanism in the early stages of a host shift than previously believed [Current Zoology 59 (5): 658-666, 2013].展开更多
基金supported by the National Natural Science Foundation of China(31560604,31160433)the Guangxi Natural Science Foundation(2015GXNSFAA139071)
文摘The morphological characteristics of the hind wing venation of tetrigids were analyzed on the basis of morphometric measurement, with 20 species and 18 different variables selected for this study. Results show that three principal components have a higher load at the length between the starting point of the costal vein and the tip of the fourth anal vein, between the tip of the costal vein and the tip of the third anal vein, and between the tip of the costal vein and the tip of the eleventh anal vein. There exists a contrast between wing length and width.
基金Acknowledgements: This study was supported by the National Natural Science Foundation of China (No. 30370195). We thank Mr QIU, H. G and QIU, Z. L for culture of insects.
文摘The ovipositor of parasitic insect is a highly specialized organ and crucial for parasitising. Morphology and structure of the ovipositor in female Macrocentrus cingulum, a polyembryonic parasitoid, are observed in SEM studies. The ovipositor of M. cingulum consists of the valvulae 1, 2 and 3. The valvulae 1 and 2 of ovipositor house in the valvulae 3 at rest and the valvulae 1 and 2 part from the valvulae 3 at probing and ovipositing. The cross-section of valvulae 3 shows that the valvulae 3 is hollow which may reduce the weight of ovipositor and make the ovipositor more flexible. The distal end of stylus (valvulae l, 2) becomes extremely sharp and the piercing tip of valvulae 1 and 2 form the arrangement of tongue-and-groove. This arrangement may support valvulae 2 slide longitudinally along the valvulae 1. Numbers of pores are distributed on the cuticle of the valvulae l and 2. The piecing tip of valvulae 1 and 2 have more pores than proximal and intermediate region. The out side of valvulae 3 is completely covered with chactica sensilla and the distal end of valvulae 3 has more sensilla than proximal and intermediate region. The function and structure of ovipositor of M. cingulum was discussed and compared with other species.
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The study of speciation genetics is primarily concerned with identifying the genetic traits that allow divergent selec- tion to overcome the homogenizing effects of gene flow. Felsenstein reviewed this race between gene flow and selection, con- cluding that speciation with gene flow was unlikely under a "two-allele model" (where two traits were necessary for reproductive isolation) but that divergence could occur quite easily under a "one-allele model." Despite this finding, much of the sympatric speciation research involving phytophagous insects has relied on a two-trait model, where insects evolve both preferences for and increased performance on novel host plants. Philopatry (a tendency to remain where one was born) is known to occur in phyto- phagous insects and is a single trait isolation mechanism. However, it is traditionally invoked as simply augmenting reproductive isolation. Species in the Enchenopa binotata complex are believed to have speciated in sympatry. They exhibit host plant prefe- rences, host specific performance advantages and strong philopatry. We experimentally shifted E. binotata to evolutionarily novel host plants. Previous research has demonstrated that the experimental population of insects possesses genetic variation in prefe- rence and performance to the novel host. The degree of philopatry at mating and egg-laying was assayed for the first four years under full choice conditions. Host plant preference and performance was assayed after eight years. Philopatry was an immediate and strong isolating mechanism, while preference for and performance on the novel host lagged. We therefore suggest that philo- patry may be a more important mechanism in the early stages of a host shift than previously believed [Current Zoology 59 (5): 658-666, 2013].