Advice of the rose: Experimental coevolution of a trematode parasite and its snail host
Advice of the rose: Experimental coevolution of a trematode parasite and its snail host
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DOI：
10.1111/j.1558-5646.2007.00012.x
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发表时间：
2007-01-01
期刊：
影响因子：
3.3
通讯作者：
Lively, Curtis M.
中科院分区：
文献类型：
--
作者：
Koskella, Britt;Lively, Curtis M.
了解宿主-寄生虫的共同进化需要进行多代研究，监测寄生虫传染性和宿主易感性的变化。我们进行了一项共同进化实验，研究了淡水蜗牛（Potamopyrgus antipodarum）和它的一种常见寄生虫（绝育吸虫，Microphallus sp.）之间的六代相互作用。在一个处理（循环）中，寄生虫被重新引入到同一种群的寄主蜗牛中。在第二次处理（滞后）中，寄主蜗牛接受了来自循环处理的寄生虫，但这些寄生虫的添加直到第二代才开始。因此，滞后处理中宿主的任何寄生虫介导的遗传变化预计比循环处理中的遗传变化晚一代。因此，滞后处理使我们能够测试寄生虫适应的时间滞后，正如宿主-寄生虫共同进化的红皇后模型所预测的那样。最后，在第三个处理（对照）中，不添加寄生虫。结果表明，再生处理的寄生虫对滞后处理的钉螺的感染性显著高于再生处理。此外，循环处理的寄主与对照寄主在对田间收集的寄生虫的易感性方面存在差异。综上所述，结果与宿主和寄生虫之间的时间滞后、频率依赖的选择和快速共同进化是一致的。
Understanding host-parasite coevolution requires multigenerational studies in which changes in both parasite infectivity and host susceptibility are monitored. We conducted a coevolution experiment that examined six generations of interaction between a freshwater snail (Potamopyrgus antipodarum) and one of its common parasites (the sterilizing trematode, Microphallus sp.). In one treatment (recycled), the parasite was reintroduced into the same population of host snails. In the second treatment (lagged), the host snails received parasites from the recycled treatment, but the addition of these parasites did not begin until the second generation. Hence any parasite-mediated genetic changes of the host in the lagged treatment were expected to be one generation behind those in the recycled treatment. The lagged treatment thus allowed us to test for time lags in parasite adaptation, as predicted by the Red Queen model of host-parasite coevolution. Finally, in the third treatment (control), parasites were not added. The results showed that parasites from the recycled treatment were significantly more infective to snails from the lagged treatment than from the recycled treatment. In addition, the hosts from the recycled treatment diverged from the control hosts with regard to their susceptibility to parasites collected from the field. Taken together, the results are consistent with time lagged, frequency-dependent selection and rapid coevolution between hosts and parasites.