Changes to influenza viruses can happen as a result of quick mutations or as the end result of a slower drift in genetic material.
发生在流感病毒上的变化，可能源于某种快速变异，也可能是遗传物质缓慢漂移的最终结果。
2
There is no doubt that most of the genetic differences between humans and other apes – and between different human populations – are due to geneticdrift.
毫无疑问，人类与猿猴之间以及不同人群之间的大部分基因差异都是因为基因漂变而产生。
3
Geneticdrift can even counteract natural selection.