After more than one hundred fifty years of the publication of On the Origin of Species by Darwin, scientists are still arguing on the relative importance of mutation and natural selection, on the driving force of orga...After more than one hundred fifty years of the publication of On the Origin of Species by Darwin, scientists are still arguing on the relative importance of mutation and natural selection, on the driving force of organismal evolution, on microevo- lution and macroevolution, etc. Such periodically repeated debates appeared to have introduced more chaos than musings. What happened and why？ Have we really considered our views, opinions and arguments under the big picture of evolution before pos- ing the questions？ Or are we talking past each other？ We do need some reflections. While we believe that the current evolutionary theory is doing fine, perhaps a refinement or re-encapsulation of its knowledge framework can help promote a better understanding of the evolutionary science as a whole and blow offthe mist over the big picture [Current Zoology 61 （1）： 217-220, 2015 ].展开更多
Phenotypic plasticity is often an adaptation of organisms to cope with temporally or spatially heter- ogenous landscapes. Like other adaptations, one would predict that different species, populations, or sexes might t...Phenotypic plasticity is often an adaptation of organisms to cope with temporally or spatially heter- ogenous landscapes. Like other adaptations, one would predict that different species, populations, or sexes might thus show some degree of parallel evolution of plasticity, in the form of parallel reaction norms, when exposed to analogous environmental gradients. Indeed, one might even ex- pect parallelism of plasticity to repeatedly evolve in multiple traits responding to the same gradi- ent, resulting in integrated parallelism of plasticity. In this study, we experimentally tested for paral- lel patterns of predator-mediated plasticity of size, shape, and behavior of 2 species and sexes of mosquitofish. Examination of behavioral trials indicated that the 2 species showed unique patterns of behavioral plasticity, whereas the 2 sexes in each species showed parallel responses. Fish shape showed parallel patterns of plasticity for both sexes and species, albeit males showed evidence of unique plasticity related to reproductive anatomy. Moreover, patterns of shape plasticity due to predator exposure were broadly parallel to what has been depicted for predator-mediated popula- tion divergence in other studies （slender bodies, expanded caudal regions, ventrally located eyes, and reduced male gonopodia）. We did not find evidence of phenotypic plasticity in fish size for ei- ther species or sex. Hence, our findings support broadly integrated parallelism of plasticity for sexes within species and less integrated parallelism for species. We interpret these findings with respect to their potential broader implications for the interacting roles of adaptation and constraint in the evolutionary origins of parallelism of plasticity in general.展开更多
文摘After more than one hundred fifty years of the publication of On the Origin of Species by Darwin, scientists are still arguing on the relative importance of mutation and natural selection, on the driving force of organismal evolution, on microevo- lution and macroevolution, etc. Such periodically repeated debates appeared to have introduced more chaos than musings. What happened and why？ Have we really considered our views, opinions and arguments under the big picture of evolution before pos- ing the questions？ Or are we talking past each other？ We do need some reflections. While we believe that the current evolutionary theory is doing fine, perhaps a refinement or re-encapsulation of its knowledge framework can help promote a better understanding of the evolutionary science as a whole and blow offthe mist over the big picture [Current Zoology 61 （1）： 217-220, 2015 ].
文摘Phenotypic plasticity is often an adaptation of organisms to cope with temporally or spatially heter- ogenous landscapes. Like other adaptations, one would predict that different species, populations, or sexes might thus show some degree of parallel evolution of plasticity, in the form of parallel reaction norms, when exposed to analogous environmental gradients. Indeed, one might even ex- pect parallelism of plasticity to repeatedly evolve in multiple traits responding to the same gradi- ent, resulting in integrated parallelism of plasticity. In this study, we experimentally tested for paral- lel patterns of predator-mediated plasticity of size, shape, and behavior of 2 species and sexes of mosquitofish. Examination of behavioral trials indicated that the 2 species showed unique patterns of behavioral plasticity, whereas the 2 sexes in each species showed parallel responses. Fish shape showed parallel patterns of plasticity for both sexes and species, albeit males showed evidence of unique plasticity related to reproductive anatomy. Moreover, patterns of shape plasticity due to predator exposure were broadly parallel to what has been depicted for predator-mediated popula- tion divergence in other studies （slender bodies, expanded caudal regions, ventrally located eyes, and reduced male gonopodia）. We did not find evidence of phenotypic plasticity in fish size for ei- ther species or sex. Hence, our findings support broadly integrated parallelism of plasticity for sexes within species and less integrated parallelism for species. We interpret these findings with respect to their potential broader implications for the interacting roles of adaptation and constraint in the evolutionary origins of parallelism of plasticity in general.
