Variation

• Variation - Differences that exist between individuals. Variations occur within species and between species
• Intraspecific - within a species
• Interspecific - between different species
• Continuous variation

  Quantitative (numerical) differences in the observable characteristics or phenotypes

  • variation can have a full range of values or phenotypes
  • two extremes with a range of values in between
  • can be measured, and the value can change over time
  • pattern shows a normal distribution curve – few individuals at the extremes

  
• Discontinuous variation

  Qualitative (descriptive) differences in the observable characteristics or phenotype

  • few discrete values the feature can have
  • two or more distinct categories with no intermediate values (e.g eye colour, sex,)
  • Members of a species may be evenly distributed between the different forms, or there may be more of one type than another
  • caused by genes and isn't effected by environment
• Discontinuous variation

  • Qualitative (descriptive) differences in the observable characteristics or phenotype
  • few discrete values the feature can have
  • two or more distinct categories with no intermediate values (e.g eye colour, sex,)
  • Members of a species may be evenly distributed between the different forms, or there may be more of one type than another
  • caused by genes and isn't effected by environment
  • Represented via bar chart