Variation is the differences between individuals of the same species, caused by genetic and environmental factors. Surveys into variation give data that are continuous, which means to come in a range, ...

Marked geographic patterns for the distribution of some heritable traits are observed in humans, including traits related to disease risk, pathogen resistance and drug response. In some cases, the ...

A characteristic of any species with only a limited number of possible values shows discontinuous variation. Here are some examples: For any species a characteristic that changes gradually over a ...