This "mechanical isolation" separates many species of dragonflies and damselflies. Incompatible gametes divide some species of shellfish that deposit their sperm and eggs directly in the water.

In natural populations, the mechanisms of evolution do not act in isolation. This is crucially important to conservation geneticists, who grapple with the implications of these evolutionary ...

They described evolution as a continuous ... evolve different traits and can no longer interbreed. It's this isolation or separation that creates new species, said Mayr. The traits that evolve ...