Analysing variation

Variation can be defined as differences that are observed amongst individuals in a population.There are many different types of variation including structural, biochemical, physiological, behavioral, development and geographical variation.

Structural variation

Difference in structures that exist amongst individuals.

Examples include:

  • Different breeds of dogs.
  • Different feather varieties in birds.
  • Difference in size of goldfish.

Biochemical variation

Differences observed amongst individuals in regards to chemicals within the body

Examples include:

  • Colours observed in animals.
  • ABO antigens on red blood cell membranes.

Physiological variation

Differences found in one of the senses.


  • Colour blindness
  • Differences in taste, vision, heating, smell and touch

Behavioral variation

Differences observed in innate behaviours


  • Difference in  the nature of a dog’s personality found amongst different dog breeds.

Developmental variation

Changes observed in members of the population that occur during their lifespan.


  • Eucalyptus plants leaf changes as it matures.
  • Snakes change colours during the lifespan.

Geographical variation

Differences in populations  due to geographical location.

For examples, differences observed amongst organisms living at different temperature and altitudes.