Research on sexual selection and hybridization has focused on female mate choice and male-male competition. While the evolutionary outcomes of interspecific female preference have been well explored, we are now gainin...Research on sexual selection and hybridization has focused on female mate choice and male-male competition. While the evolutionary outcomes of interspecific female preference have been well explored, we are now gaining a better understanding of the processes by which male-male compe- tition between species in secondary contact promotes reproductive isolation versus hybridization. What is relatively unexplored is the interaction between female choice and male competition, as they can oppose one another or align with similar outcomes for reproductive isolation. The role of female-female competition in hybridization is also not well understood, but could operate similarly to male-male competition in polyandrous and other systems where costs to heterospecific mating are low for females. Reproductive competition between either sex of sympatric species can cause the divergence and/or convergence of sexual signals and recognition, which in turn influences the likelihood for interspecific mating. Future work on species interactions in secondary contact should test the relative influences of both mate choice and competition for mates on hybridization outcomes, and should not ignore the possibilities that females can compete over mating resources, and males can exercise mate choice.展开更多
Aggressive behavior can be an important factor in determining how animals use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including ...Aggressive behavior can be an important factor in determining how animals use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including water temperature and resource levels. In this study, we tested if the amount of habitat structure in the environment affected aggression levels in female convict cichlids Archocentrus nigrofasciatus. We performed a laboratory experiment in which we placed female convict cichlids into an aquarium with low or high amounts of habitat structure and monitored the dominant female＇s behavior toward the subordinate female. Aggressive behavior in convict cichlids primarily consists of chases and bites. We found that the total time the dominant female spent chasing the subordinate female was greater when there was a low amount of habitat structure as compared to when there was a high amount of habitat structure. We also found that both the average duration of a chasing bout and the number of bites directed at the subordinate fish increased when there was a low amount of structure, but the number of chases did not. These results indicate that increased habitat structural complexity decreases aggressive behavior in convict cichlids [Current Zoology 56 （1）： 52-56, 2010].展开更多
为了证明尖唇散白蚁Reticulitermes aculabialis Tsai et Hwang是否存在孤雌生殖行为和探讨其初建群体的发育特征，本文对尖唇散白蚁分飞成虫进行雌雌配对（FF）和雌雄配对（FM）人工饲养对比研究。结果显示：FM和FF组的筑巢时间和筑巢...为了证明尖唇散白蚁Reticulitermes aculabialis Tsai et Hwang是否存在孤雌生殖行为和探讨其初建群体的发育特征，本文对尖唇散白蚁分飞成虫进行雌雌配对（FF）和雌雄配对（FM）人工饲养对比研究。结果显示：FM和FF组的筑巢时间和筑巢活动相似；在建巢初期（配对第5天）FF配对组和FM配对组死亡率分别为11．33％和2．67％，FF配对组死亡率显著高于FM组；产卵前FM组的2只雌性个体和FF组的雌性个体卵巢发育程度一致，都有已经完成卵黄积累的成熟卵母细胞。6个月后，FF配对组有7组产生后代，FM配对组有17组产生后代；FF组子代数目显著低于FM组，分别平均为（7．00±1．58）个和（10．33±1．21）个；FF子代全为2～3龄工蚁，而FM组有由3-4龄工蚁分化的低龄兵蚁。最后，我们对新建群体分化出的第一只兵蚁与成熟巢群中的兵蚁进行了形态学比较。我们的结果表明，尖唇散白蚁具有孤雌生殖行为，并且分飞成虫通过雌雌配对和雌雄配对初建群体在发育模式上有显著差异，雌雌成虫配对采用孤雌生殖方式繁殖有可能是野外尖唇散白蚁建群的另一种方式。展开更多
基金S.E.L. was supported by a National Science Foundation （NSF） Graduate Research Opportunities Worldwide （GROW） Fellowship in Switzerland and NSF Graduate Research Fellowship under Grant No. 1154145. Any opinion, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the NSF.
文摘Research on sexual selection and hybridization has focused on female mate choice and male-male competition. While the evolutionary outcomes of interspecific female preference have been well explored, we are now gaining a better understanding of the processes by which male-male compe- tition between species in secondary contact promotes reproductive isolation versus hybridization. What is relatively unexplored is the interaction between female choice and male competition, as they can oppose one another or align with similar outcomes for reproductive isolation. The role of female-female competition in hybridization is also not well understood, but could operate similarly to male-male competition in polyandrous and other systems where costs to heterospecific mating are low for females. Reproductive competition between either sex of sympatric species can cause the divergence and/or convergence of sexual signals and recognition, which in turn influences the likelihood for interspecific mating. Future work on species interactions in secondary contact should test the relative influences of both mate choice and competition for mates on hybridization outcomes, and should not ignore the possibilities that females can compete over mating resources, and males can exercise mate choice.
基金Acknowledgements We thank Samantha Hilber for valuable comments on the manuscriPt. RMC thanks G.W. Barlow for countless discussions about behavior and for his unbounded enthusiasm for fishes.
文摘Aggressive behavior can be an important factor in determining how animals use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including water temperature and resource levels. In this study, we tested if the amount of habitat structure in the environment affected aggression levels in female convict cichlids Archocentrus nigrofasciatus. We performed a laboratory experiment in which we placed female convict cichlids into an aquarium with low or high amounts of habitat structure and monitored the dominant female＇s behavior toward the subordinate female. Aggressive behavior in convict cichlids primarily consists of chases and bites. We found that the total time the dominant female spent chasing the subordinate female was greater when there was a low amount of habitat structure as compared to when there was a high amount of habitat structure. We also found that both the average duration of a chasing bout and the number of bites directed at the subordinate fish increased when there was a low amount of structure, but the number of chases did not. These results indicate that increased habitat structural complexity decreases aggressive behavior in convict cichlids [Current Zoology 56 （1）： 52-56, 2010].
文摘为了证明尖唇散白蚁Reticulitermes aculabialis Tsai et Hwang是否存在孤雌生殖行为和探讨其初建群体的发育特征，本文对尖唇散白蚁分飞成虫进行雌雌配对（FF）和雌雄配对（FM）人工饲养对比研究。结果显示：FM和FF组的筑巢时间和筑巢活动相似；在建巢初期（配对第5天）FF配对组和FM配对组死亡率分别为11．33％和2．67％，FF配对组死亡率显著高于FM组；产卵前FM组的2只雌性个体和FF组的雌性个体卵巢发育程度一致，都有已经完成卵黄积累的成熟卵母细胞。6个月后，FF配对组有7组产生后代，FM配对组有17组产生后代；FF组子代数目显著低于FM组，分别平均为（7．00±1．58）个和（10．33±1．21）个；FF子代全为2～3龄工蚁，而FM组有由3-4龄工蚁分化的低龄兵蚁。最后，我们对新建群体分化出的第一只兵蚁与成熟巢群中的兵蚁进行了形态学比较。我们的结果表明，尖唇散白蚁具有孤雌生殖行为，并且分飞成虫通过雌雌配对和雌雄配对初建群体在发育模式上有显著差异，雌雌成虫配对采用孤雌生殖方式繁殖有可能是野外尖唇散白蚁建群的另一种方式。
