genetics diversity

• genetic diversity

  total number of different alleles of each gene in a population
• natural selection

  species becoming more adapted to their environment

  process of natural selection would lead to evolution occuring
• process of natural selection

  new alleles caused by random gene mutations

  if the new alleles increases the chances of survival, they are more likely to reproduce

  advantageous allele passed onto whilst reproducing

  new allele increase in frequency within the population
• directional selection

  only occurs in environmental change 

  Extreme traits have a selective advantage

  (eg antibiotic resistance)

  favours an extreme phenotype
• stabilising selection

  no environmental change

  modal trait has a selective advantage so it remains the same

  favours an average phenotype