Inverting the null-hypothesis of speciation: a marine snail perspective

  title={Inverting the null-hypothesis of speciation: a marine snail perspective},
  author={Kerstin Johannesson},
  journal={Evolutionary Ecology},
Speciation is currently an intensely debated topic, much more so than 20–30 years ago when most biologists held the view that new species (at least of animals) were formed through the split of evolutionary lineages by the appearance of physical barriers to gene flow. Recent advances have, however, lent both theoretical and empirical support to speciation in the presence of gene flow. Nevertheless, the allopatric hypothesis of speciation is still the default model. The consequence of this is… 

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