Organisms of the same species vary in many ways. There are two types of variation – continuous and discontinuous. Natural selection explains how evolution occurs.
Part of Combined ScienceGenetics
This is a gradual change in a characteristic across a population, it could be human height, mass and shoe size.
Continuous variation is represented as a histogramclosehistogram A graphical representation of the distribution of numerical data..
A histogram should show normal distribution, with most individuals around the average value and a few at the extremes.
A characteristic of any species with only a limited number of possible values shows discontinuous variation. For example:
Human beings have one of four blood groups, A, B, AB or O.
There are no values in between (intermediate values), so this shows discontinuous variation.
Discontinuous variation is represented as a bar chart.