variation and evolution

• variation

  differences in the characteristics of individuals in a population
• genetic variation: hair colour, eye colour
• variation caused by environment : languages, height, colour of the flowers depends on soil
• genetic variation happen due to mutations which are random changes to DNA
• mutation can lead to new phenotype which will be beneficial if suitable for the environment changes which leads a rapid change in species
• every species will have a slightly different combination of alleles inherited from their parents
• natural selection

  over many generations, the allele that has more survival chances will be more common among their population
• evolution

  change in the inherited characteristics of a population over time through a process of natural selection