variation and selection

• Individuals with advantageous traits have higher chances of surviving and reproducing, passing on their favorable genes to future generations.
• • Variation is defined as differences between individuals of the same species
• • Phenotypic variation is the difference in features between individuals of the same species
• • Some of these differences are caused by differences in genes, which is genetic variation
• • Phenotypic variation:
  • It can be genetic - controlled entirely by genes
  • Or it can be environmental - caused entirely by the environment in which the organism lives
• • Examples of genetic variation in humans include:
  • blood group
  • eye colour
  • gender
  • ability to roll tongue
  • whether ear lobes are free or fixed