Other, more gradual changes can be a sign of refractive errors. Usually, your best option whenever you experience blurred vision in one eye is to get it checked by a doctor, says Farzan Gorgani ...

Now it is widely recognized as a useful model for one kind of evolutionary change. The relative importance of punctuated and gradual patterns of evolution is a subject of debate and research.

Darwin and his later followers were faced with a seeming paradox. They described evolution as a continuous, gradual change over time, but species are distinct from each other, suggesting that some ...