This is a gradual change in a characteristic across a population, it could be human height, mass and shoe size. Human beings have one of four blood groups, A, B, AB or O. There are no values in ...

I HAVE just received a copy of Mr. Bateson's most valuable work on the “Study of Variation”; and although it will take many weeks to read it as it deserves to be read, a few remarks are now ventured ...