Reproductive isolation is the basis of the Biological Species Definition and can be a driving force of speciation. Theoretical studies have provided models of how reproductive isolation can arise within individual spe...Reproductive isolation is the basis of the Biological Species Definition and can be a driving force of speciation. Theoretical studies have provided models of how reproductive isolation can arise within individual species. Genetic tests of these models are limited to populations in which reproductive isolation is present but not complete. Here, reproductive isolation in the Elgans-Group of the nematode genus Caenorhabditis is reviewed. Pre-mating barriers, assortative fertilization and post-zygotic barriers all have been observed in this clade. In some combinations of species, fertile F1 hybrids can be obtained. Therefore, the Elegans-Group of Caenorhabditis is poised to become an important experimental system for the study of reproductive isolation.展开更多
Niche differentiation enables ecologically similar species to coexist by lessening competition over food and/or shelters and may be critical for reproductive isolation between closely related species in close proximit...Niche differentiation enables ecologically similar species to coexist by lessening competition over food and/or shelters and may be critical for reproductive isolation between closely related species in close proximity.Because no extra traits need to evolve,spatial and temporal differentiation may readily take place to complement other isolating mechanisms.Two closely related treefrog species occur together in Korea:the endangered Hyla suweonensis and the widespread Hyla japonica.Advertisement calls are differentiated,but it is unclear whether call difference is sufficient for reproductive isolation.We tracked individuals of both species to study fine-scale differentiation in microhabitat use in the diel cycle of the breeding season using a harmonic direction finder.tracking male movement patterns of both species revealed spatial and temporal differentiation in microhabitat use for calling and resting during the breeding season.Males of both H.suweonensis and H.japonica occurred in all 5 microhabitats identified in this study:rice paddy,ground,buried,grass and bush.Both treefrog species showed general similarities in calling from rice paddies and resting in grass and bush.However,H.suweonensis moved into rice paddies and produced advertisement calls 3 h earlier than H.japonica.These differences likely minimize contact between the species and provide an additional isolating mechanism.In addition,the activity of H.suweonensis may be contributing to the decline of this species,as resting in grass would increase dangers from predatory birds and habitat disturbance.展开更多
文摘Reproductive isolation is the basis of the Biological Species Definition and can be a driving force of speciation. Theoretical studies have provided models of how reproductive isolation can arise within individual species. Genetic tests of these models are limited to populations in which reproductive isolation is present but not complete. Here, reproductive isolation in the Elgans-Group of the nematode genus Caenorhabditis is reviewed. Pre-mating barriers, assortative fertilization and post-zygotic barriers all have been observed in this clade. In some combinations of species, fertile F1 hybrids can be obtained. Therefore, the Elegans-Group of Caenorhabditis is poised to become an important experimental system for the study of reproductive isolation.
基金supported financially by the National Research Foundation of Korea(grant number 2012R1A2A2A01046977).
文摘Niche differentiation enables ecologically similar species to coexist by lessening competition over food and/or shelters and may be critical for reproductive isolation between closely related species in close proximity.Because no extra traits need to evolve,spatial and temporal differentiation may readily take place to complement other isolating mechanisms.Two closely related treefrog species occur together in Korea:the endangered Hyla suweonensis and the widespread Hyla japonica.Advertisement calls are differentiated,but it is unclear whether call difference is sufficient for reproductive isolation.We tracked individuals of both species to study fine-scale differentiation in microhabitat use in the diel cycle of the breeding season using a harmonic direction finder.tracking male movement patterns of both species revealed spatial and temporal differentiation in microhabitat use for calling and resting during the breeding season.Males of both H.suweonensis and H.japonica occurred in all 5 microhabitats identified in this study:rice paddy,ground,buried,grass and bush.Both treefrog species showed general similarities in calling from rice paddies and resting in grass and bush.However,H.suweonensis moved into rice paddies and produced advertisement calls 3 h earlier than H.japonica.These differences likely minimize contact between the species and provide an additional isolating mechanism.In addition,the activity of H.suweonensis may be contributing to the decline of this species,as resting in grass would increase dangers from predatory birds and habitat disturbance.
