In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relati...In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relationship is usually established. In subsequent interactions, the loser will flee soon after detecting the familiar winner. Here we tested the hypothesis that losing a fight with a conspecific will affect future agonistic interactions not only toward that individual （i.e., the familiar winner） but also toward unfamiliar conspecifics. To test this hypothesis we paired two Syrian hamster males in three trials on one day in which the loser had tile opportunity to escape the winner. The next day the loser was paired with an unfarniliar male, also for three trials. If he lost again, he was tested on a third day with a third unfamiliar male. Subjects were those males that were losers on all three days. The latency to escape on the first trial on Days 2 and 3 was significantly shorter than on the first trial on Day l, indicating that losing against the first male affected the response toward unfamiliar males. However, the latency to escape on the first trial on Days 2 and 3 was significantly longer than that on the third trial on the preceding day, indicating that a loser treats unfamiliar males differently than a familiar winner. These results suggest that a defeat during an interaction with one male affects later agonistic behavior towards other, unfamiliar males [Current Zoology 57 （4）： 449-452, 2011].展开更多
An agonistic display by a white shark was observed and photographed during a cage dive at Guadalupe Island in November 2015. Exhibiting exaggerated pectoral fin depression, agonistic behaviors have been previously obs...An agonistic display by a white shark was observed and photographed during a cage dive at Guadalupe Island in November 2015. Exhibiting exaggerated pectoral fin depression, agonistic behaviors have been previously observed and described in several shark species. This account may be the first record of a white shark in close proximity to a caged diver, exhibiting strong pectoral fin depression significantly dipped, in the mid-agonistic display. Such displays should be considered as aggressive and potentially life-threatening by those using the ocean for recreational or professional purposes.展开更多
Aggression is a common behavioral strategy employed by animals to secure limited resources, but must be applied with restraint to limit potential costs including injury. How animals make the adap- tive decision to fig...Aggression is a common behavioral strategy employed by animals to secure limited resources, but must be applied with restraint to limit potential costs including injury. How animals make the adap- tive decision to fight or flee is barely known. Here, we review our work on crickets that reveals the roles of biogenic amines, primarily octopamine （the insect analog of noradrenaline） and nitric oxide （NO）. Using aminergic drugs, we found that amines are not essential for actually initiating aggres- sion. However, octopamine is necessary for mediating the aggression-promoting effects of poten- tially rewarding experiences including stimulation with a male antenna, physical exertion, winning, and resource possession. Hence, octopamine can be considered as the motivational component of aggression. Imposed handicaps that impede aggressive signaling revealed that the agonistic actions of an opponent perceived during fighting act to reduce aggression, and that crickets make the deci- sion to flee the moment the accumulated sum of such aversive experiences exceeds some critical level. Treatment with nitridergic drugs revealed that the impact of the opponent＇s aggressive actions is mediated by NO. NO acts to suppress aggression by promoting the tendency to flee and is primarily responsible for the depressed aggressiveness of subordinates after social defeat. Octopamine and dopamine can each restore aggression in subordinates, but only dopamine is necessary for normal recovery. The role of serotonin remains unclear, and is discussed. We conclude that octopamine and NO control the decision to fight or flee by mediating the effects of potentially rewarding and aversive experiences, respectively.展开更多
We investigated how the parasitoid Torymus sp. (Hymenoptera: Torymidae) attacking galls of Schismatodiplosis lantanae (Diptera: Cecidomyiidae) on Lantana camara (Verbenaceae) behaves in the presence of a conspecific f...We investigated how the parasitoid Torymus sp. (Hymenoptera: Torymidae) attacking galls of Schismatodiplosis lantanae (Diptera: Cecidomyiidae) on Lantana camara (Verbenaceae) behaves in the presence of a conspecific female competitor in the patch. Presence of a competitor greatly changed resident exploitation behavior. Wasps alone spent more time in gall exploitation behaviors (walk-antennate and probe) and in post-oviposition behaviors (stationary and groom), and when intruders were present they spent more time walking. The attack strategy was through threatening: raising wings and pointing the antennae towards the opponent. Different from theoretical expectations, residents were not always the attacker. Number of galls in the patch and female wasp size did not affect contest outcomes, although gall exploitation time and time on leaf were significant factors for the probability of having attacks. Overall, the study highlights the fact that intruder interest in the host was the main cause of contests and also this is a unique report both in terms of the target species and the nature of the disputed resource, a gall-inducer inside a singular spatial unit, the gall.展开更多
Spiders are an abundant group of natural enemies preying on insect pests in agroecosystem.But their potential in biological control has not been fully realized due to difficult mass production.One hindrance is the int...Spiders are an abundant group of natural enemies preying on insect pests in agroecosystem.But their potential in biological control has not been fully realized due to difficult mass production.One hindrance is the intense intraspecific aggression in spiders.Neurotransmitters such as serotonin play important roles in modulating aggression.Here,we investigated the regulatory function of serotonin(5-hydroxytryptamine[5-HT])signaling in the intraspecific aggression in a wandering spider Pardosa pseudoannulata(Araneae,Lycosidae).The aggression was quantified with 5 escalated aggression behaviors as approach,chasing,lunging,boxing,and biting.Virgin(VG)females exhibited higher aggression levels but less 5-HT content than post-reproductive(PR)females.Systemic increase of 5-HT via 5-HT injection decreased aggression,while decrease of 5-HT via RNA interference(RNAi)of the tryptophan hydroxylase gene,increased aggression.The involvement of the four 5-HT receptors were determined via individual or combined RNAi.Co-RNAi of the three 5-HT1 genes increased overall aggression with decreased incidents of approach,chasing,lunging,and increased biting.RNAi of 5-HT1B decreased approach and increased biting,whereas RNAi of 5-HT1A or 5-HT1C did not affect aggression.RNAi of 5-HT7 decreased approach only.Therefore,different 5-HT receptor types contribute to different aspects of the inhibitory effects of 5-HT on aggression and provide several pharmacological targets for manipulating spider aggression.5-HT injection did not affect spiders’predation on their insect prey,the brown planthopper Nilaparvata lugens.The findings reveal 1 neuronal mechanism regulating intraspecific aggression in spiders and provide an insight in developing aggression suppression strategies for spider mass rearing.展开更多
文摘In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relationship is usually established. In subsequent interactions, the loser will flee soon after detecting the familiar winner. Here we tested the hypothesis that losing a fight with a conspecific will affect future agonistic interactions not only toward that individual （i.e., the familiar winner） but also toward unfamiliar conspecifics. To test this hypothesis we paired two Syrian hamster males in three trials on one day in which the loser had tile opportunity to escape the winner. The next day the loser was paired with an unfarniliar male, also for three trials. If he lost again, he was tested on a third day with a third unfamiliar male. Subjects were those males that were losers on all three days. The latency to escape on the first trial on Days 2 and 3 was significantly shorter than on the first trial on Day l, indicating that losing against the first male affected the response toward unfamiliar males. However, the latency to escape on the first trial on Days 2 and 3 was significantly longer than that on the third trial on the preceding day, indicating that a loser treats unfamiliar males differently than a familiar winner. These results suggest that a defeat during an interaction with one male affects later agonistic behavior towards other, unfamiliar males [Current Zoology 57 （4）： 449-452, 2011].
文摘An agonistic display by a white shark was observed and photographed during a cage dive at Guadalupe Island in November 2015. Exhibiting exaggerated pectoral fin depression, agonistic behaviors have been previously observed and described in several shark species. This account may be the first record of a white shark in close proximity to a caged diver, exhibiting strong pectoral fin depression significantly dipped, in the mid-agonistic display. Such displays should be considered as aggressive and potentially life-threatening by those using the ocean for recreational or professional purposes.
文摘Aggression is a common behavioral strategy employed by animals to secure limited resources, but must be applied with restraint to limit potential costs including injury. How animals make the adap- tive decision to fight or flee is barely known. Here, we review our work on crickets that reveals the roles of biogenic amines, primarily octopamine （the insect analog of noradrenaline） and nitric oxide （NO）. Using aminergic drugs, we found that amines are not essential for actually initiating aggres- sion. However, octopamine is necessary for mediating the aggression-promoting effects of poten- tially rewarding experiences including stimulation with a male antenna, physical exertion, winning, and resource possession. Hence, octopamine can be considered as the motivational component of aggression. Imposed handicaps that impede aggressive signaling revealed that the agonistic actions of an opponent perceived during fighting act to reduce aggression, and that crickets make the deci- sion to flee the moment the accumulated sum of such aversive experiences exceeds some critical level. Treatment with nitridergic drugs revealed that the impact of the opponent＇s aggressive actions is mediated by NO. NO acts to suppress aggression by promoting the tendency to flee and is primarily responsible for the depressed aggressiveness of subordinates after social defeat. Octopamine and dopamine can each restore aggression in subordinates, but only dopamine is necessary for normal recovery. The role of serotonin remains unclear, and is discussed. We conclude that octopamine and NO control the decision to fight or flee by mediating the effects of potentially rewarding and aversive experiences, respectively.
文摘We investigated how the parasitoid Torymus sp. (Hymenoptera: Torymidae) attacking galls of Schismatodiplosis lantanae (Diptera: Cecidomyiidae) on Lantana camara (Verbenaceae) behaves in the presence of a conspecific female competitor in the patch. Presence of a competitor greatly changed resident exploitation behavior. Wasps alone spent more time in gall exploitation behaviors (walk-antennate and probe) and in post-oviposition behaviors (stationary and groom), and when intruders were present they spent more time walking. The attack strategy was through threatening: raising wings and pointing the antennae towards the opponent. Different from theoretical expectations, residents were not always the attacker. Number of galls in the patch and female wasp size did not affect contest outcomes, although gall exploitation time and time on leaf were significant factors for the probability of having attacks. Overall, the study highlights the fact that intruder interest in the host was the main cause of contests and also this is a unique report both in terms of the target species and the nature of the disputed resource, a gall-inducer inside a singular spatial unit, the gall.
基金supported by the National Natural Science Foundation(grant number 32172482)China National University Student Innovation&Entrepreneurship Development Program(grant number 202310307046Z).
文摘Spiders are an abundant group of natural enemies preying on insect pests in agroecosystem.But their potential in biological control has not been fully realized due to difficult mass production.One hindrance is the intense intraspecific aggression in spiders.Neurotransmitters such as serotonin play important roles in modulating aggression.Here,we investigated the regulatory function of serotonin(5-hydroxytryptamine[5-HT])signaling in the intraspecific aggression in a wandering spider Pardosa pseudoannulata(Araneae,Lycosidae).The aggression was quantified with 5 escalated aggression behaviors as approach,chasing,lunging,boxing,and biting.Virgin(VG)females exhibited higher aggression levels but less 5-HT content than post-reproductive(PR)females.Systemic increase of 5-HT via 5-HT injection decreased aggression,while decrease of 5-HT via RNA interference(RNAi)of the tryptophan hydroxylase gene,increased aggression.The involvement of the four 5-HT receptors were determined via individual or combined RNAi.Co-RNAi of the three 5-HT1 genes increased overall aggression with decreased incidents of approach,chasing,lunging,and increased biting.RNAi of 5-HT1B decreased approach and increased biting,whereas RNAi of 5-HT1A or 5-HT1C did not affect aggression.RNAi of 5-HT7 decreased approach only.Therefore,different 5-HT receptor types contribute to different aspects of the inhibitory effects of 5-HT on aggression and provide several pharmacological targets for manipulating spider aggression.5-HT injection did not affect spiders’predation on their insect prey,the brown planthopper Nilaparvata lugens.The findings reveal 1 neuronal mechanism regulating intraspecific aggression in spiders and provide an insight in developing aggression suppression strategies for spider mass rearing.
