Institute of Evolutionary Biology, University of Edinburgh, , Kings Buildings, Ashworth Laboratories, West Mains Road, Edinburgh EH9 3JT, UK.
Proc Biol Sci. 2011 Jan 22;278(1703):247-55. doi: 10.1098/rspb.2010.1173. Epub 2010 Aug 4.
When competitive exclusion between lineages and genetic adaptation within lineages occur on the same timescale, the two processes have the potential to interact. I use experimental microbial evolution where strains of a photosynthetic microbe that differ in their physiological response to CO(2) enrichment are grown either alone or in communities for hundreds of generations under CO(2) enrichment. After about 300 generations of growth, strains that experienced competition while adapting to environmental change are both less productive and less fit than corresponding strains that adapted to that same environmental change in the absence of competitors. In addition, I find that excluding competitors not only limits that strain's adaptive response to abiotic change, but also decreases community productivity; I quantify this effect using the Price equation. Finally, these data allow me to empirically test the common hypothesis that phytoplankton that are most able to take advantage of carbon enrichment in single-strain populations over the short term will increase in frequency within multi-strain communities over longer timescales.
当谱系间的竞争排斥和谱系内的遗传适应发生在同一时间尺度上时，这两个过程有可能相互作用。我使用实验微生物进化，在 CO(2)富集条件下，对光合作用微生物的菌株进行数百代的单独或群落培养，这些菌株在生理上对 CO(2)富集的反应存在差异。在大约 300 代的生长之后，与在没有竞争的情况下适应环境变化的相应菌株相比，经历了竞争的菌株的生产力和适应性都较低。此外，我发现排除竞争者不仅限制了该菌株对非生物变化的适应性反应，而且还降低了群落的生产力；我使用 Price 方程对这种效应进行了量化。最后，这些数据使我能够从经验上检验一个常见的假设，即那些在短期内最能够利用单菌株种群中碳富集的浮游植物，在更长的时间尺度内，在多菌株群落中的频率将会增加。
