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添加8字节 、 2022年3月6日 (日) 18:26
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From these assumptions, geographic mosaic theory suggests that natural selection on interactions among species is driven by three sources of variation:
 
From these assumptions, geographic mosaic theory suggests that natural selection on interactions among species is driven by three sources of variation:
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根据这些假设,地理镶嵌理论表明物种间相互作用的自然选择由三个变异来源驱动:
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根据这些假设的地理镶嵌理论表明物种间相互作用的自然选择由三个变异来源驱动:
    
1. ''Geographic selection mosaics'' occur in interactions among species, because genes are expressed in different ways in different environments and because different genes are favored in different environments. For example, natural selection on an interaction between a parasite population and a host population may differ between very dry environments and very wet environments. Alternatively, an interaction between two or more species may be antagonistic in some environments but mutualistic (beneficial to both or all species) in other environments.
 
1. ''Geographic selection mosaics'' occur in interactions among species, because genes are expressed in different ways in different environments and because different genes are favored in different environments. For example, natural selection on an interaction between a parasite population and a host population may differ between very dry environments and very wet environments. Alternatively, an interaction between two or more species may be antagonistic in some environments but mutualistic (beneficial to both or all species) in other environments.
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2. Coevolutionary hotspots and coldspots occur because natural selection on interactions among species is reciprocal in some environments but not in others. For example, a symbiont population may decrease the survival or reproduction of its hosts in one environment, but it may have no effect on host survival or reproduction in another environment. When detrimental, natural selection will favor evolutionary responses in the host population, resulting in a coevolutionary hotspot of ongoing reciprocal evolutionary changes in the parasite and host populations. When the symbiont has no effect on the survival and reproduction of the host, natural selection on the symbiont population will not favor an evolutionary response by the host population (i.e, a coevolutionary coldspot).
 
2. Coevolutionary hotspots and coldspots occur because natural selection on interactions among species is reciprocal in some environments but not in others. For example, a symbiont population may decrease the survival or reproduction of its hosts in one environment, but it may have no effect on host survival or reproduction in another environment. When detrimental, natural selection will favor evolutionary responses in the host population, resulting in a coevolutionary hotspot of ongoing reciprocal evolutionary changes in the parasite and host populations. When the symbiont has no effect on the survival and reproduction of the host, natural selection on the symbiont population will not favor an evolutionary response by the host population (i.e, a coevolutionary coldspot).
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2.共同进化热点和冷点的出现是因为物种间相互作用的自然选择在某些环境中是相互的,而在其他环境中则不然。例如,一个共生生物种群可能会减少其宿主在一个环境中的生存或繁殖,但它可能对宿主在另一个环境中的生存或繁殖没有影响。当有害时,自然选择将有利于宿主种群的进化反应,从而导致寄生虫和宿主种群中正在进行的相互进化变化的共同进化热点。当共生生物对宿主的生存和繁殖没有影响时,共生生物种群的自然选择不利于宿主种群的进化反应(即共同进化的冷斑)。
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2. ''共同演化的热点和冷点''的出现是因为物种间相互作用的自然选择在某些环境中是相互的,而在其他环境中则不然。例如,一个共生生物种群可能会减少其宿主在一个环境中的生存或繁殖,但它可能对宿主在另一个环境中的生存或繁殖没有影响。当有害时,自然选择将有利于宿主种群的进化反应,从而导致寄生虫和宿主种群中正在进行的相互进化变化的共同进化热点。当共生生物对宿主的生存和繁殖没有影响时,共生生物种群的自然选择不利于宿主种群的进化反应(即共同进化的冷斑)。
    
3. Finally, there is constant ''remixing of the traits'' on which natural selection acts both locally and regionally. At any moment in time, a local population will have a unique combination of genes on which natural selection acts. These genetic differences among populations occur because each local population has a unique history of new mutations, genomic alterations (e.g., whole genome duplications), gene flow among populations from individuals arriving from other populations or going to other populations, random loss or fixation of genes at times when populations are small (random genetic drift), hybridization with other species, and other genetic and ecological processes that affect the raw genetic material on which natural selection acts. More formally, then, the geographic mosaic of coevolution can be viewed as a genotype by genotype by environment interaction (GxGxE) that results in the relentless evolution of interacting species.
 
3. Finally, there is constant ''remixing of the traits'' on which natural selection acts both locally and regionally. At any moment in time, a local population will have a unique combination of genes on which natural selection acts. These genetic differences among populations occur because each local population has a unique history of new mutations, genomic alterations (e.g., whole genome duplications), gene flow among populations from individuals arriving from other populations or going to other populations, random loss or fixation of genes at times when populations are small (random genetic drift), hybridization with other species, and other genetic and ecological processes that affect the raw genetic material on which natural selection acts. More formally, then, the geographic mosaic of coevolution can be viewed as a genotype by genotype by environment interaction (GxGxE) that results in the relentless evolution of interacting species.
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