Sexual conflict is common in animals,and female sexual cannibalism represents an extreme form of sexual conflict.Males in many species have evolved a variety of strategies to circumvent or decrease the risk of female ...Sexual conflict is common in animals,and female sexual cannibalism represents an extreme form of sexual conflict.Males in many species have evolved a variety of strategies to circumvent or decrease the risk of female sexual cannibalism.Opportunistic mating,by which a male mates with a female when she is disturbed or when she is feeding or undertaking moulting,is one of such kinds of strategies,and widely occurs in many animals,especially in spiders.However,whether the occurrence of male opportunistic mating depends on the intensity of female sexual cannibalism remains largely unexplored.We predicted a positive correlation between them.In this study,we tested this prediction by performing a series of mating trials in the laboratory using 3 species of web-building spiders with different intensities of female sexual cannibalism:Nephila pilipes,Nephilengys malabarensis,and Parasteatoda tepidariorum.We found that the occurrence of male opportunistic mating was positively,though not statistically significantly,correlated with the intensity of female sexual cannibalism,thus supporting our hypothesis.All together,we provide evidence that male opportunistic mating may have evolved to respond to the selection pressure posed by female sexual cannibalism.展开更多
Orb-web spiders and their webs constitute an ideal model system in which to study behavioural flexibility and spatial cognition in invertebrates due to the easily quantifiable nature of the orb web. A large number of ...Orb-web spiders and their webs constitute an ideal model system in which to study behavioural flexibility and spatial cognition in invertebrates due to the easily quantifiable nature of the orb web. A large number of studies demonstrate how spiders are able to modify the geometry of their webs in response to a range of different conditions including the ability to adapt their webs to spatial constraints. However, the mechanisms behind this impressive web-building flexibility in these cognitively limited animals remain poorly explored. One possible mechanism though may be spatial learning during the spiders' exploration of their immediate surroundings. This review discusses the importance of exploration behaviour, the reliance on simple behavioural rules, and the use of already laid threads as guidelines for web-building in orb-web spiders. The focus is on the spiders' ability to detect and adapt their webs to space limitations and other spatial disruptions. I will also review the few published studies on how spatial information is gathered during the exploration phase and discuss the possibility of the use of 'cognitive map'-like processes in spiders. Finally, the review provides suggestions for designing experimental studies to shed light on whether spiders gather metric information during the site exploration (cognitive map hypothesis) or rely on more simple binary information in combination with previously laid threads to build their webs (stigmergy hypothesis).展开更多
基金This work was supported by grants from the National Natural Science Foundation of China(NSFC-31801979 and 31872229)the Singapore Ministry of Education(MOE)AcRF Tier 1 grant(R-154-000-B18-114).
文摘Sexual conflict is common in animals,and female sexual cannibalism represents an extreme form of sexual conflict.Males in many species have evolved a variety of strategies to circumvent or decrease the risk of female sexual cannibalism.Opportunistic mating,by which a male mates with a female when she is disturbed or when she is feeding or undertaking moulting,is one of such kinds of strategies,and widely occurs in many animals,especially in spiders.However,whether the occurrence of male opportunistic mating depends on the intensity of female sexual cannibalism remains largely unexplored.We predicted a positive correlation between them.In this study,we tested this prediction by performing a series of mating trials in the laboratory using 3 species of web-building spiders with different intensities of female sexual cannibalism:Nephila pilipes,Nephilengys malabarensis,and Parasteatoda tepidariorum.We found that the occurrence of male opportunistic mating was positively,though not statistically significantly,correlated with the intensity of female sexual cannibalism,thus supporting our hypothesis.All together,we provide evidence that male opportunistic mating may have evolved to respond to the selection pressure posed by female sexual cannibalism.
文摘Orb-web spiders and their webs constitute an ideal model system in which to study behavioural flexibility and spatial cognition in invertebrates due to the easily quantifiable nature of the orb web. A large number of studies demonstrate how spiders are able to modify the geometry of their webs in response to a range of different conditions including the ability to adapt their webs to spatial constraints. However, the mechanisms behind this impressive web-building flexibility in these cognitively limited animals remain poorly explored. One possible mechanism though may be spatial learning during the spiders' exploration of their immediate surroundings. This review discusses the importance of exploration behaviour, the reliance on simple behavioural rules, and the use of already laid threads as guidelines for web-building in orb-web spiders. The focus is on the spiders' ability to detect and adapt their webs to space limitations and other spatial disruptions. I will also review the few published studies on how spatial information is gathered during the exploration phase and discuss the possibility of the use of 'cognitive map'-like processes in spiders. Finally, the review provides suggestions for designing experimental studies to shed light on whether spiders gather metric information during the site exploration (cognitive map hypothesis) or rely on more simple binary information in combination with previously laid threads to build their webs (stigmergy hypothesis).