Classification

• What are the different classification methods?

  • Original methods bases on visible similarities-appearance, behaviour, fossils.
  • Modern and accurate methods-DNA sequence, mRNA sequence, amino acids sequence, Immunological by comparing similarity in self-antibody shape.
• Why do we need classification systems to organise species?

  • To understand relationships between organisms and keep track of changes, the system used needs to be universal and is based on putting organisms into groups.
  • Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.
  • Each group is called a taxa.
• What is a hierarchy?

  Smaller groups within larger groups, where there is no overlap between groups.
• What is species richness?


  The number of different species in a particular area at the particular time
• Why do different species look familiar?

  • They live in a similar environment
  • They have similar selection pressures.
  • They have similar alleles that have the same selective advantage
  • They produce similar/same proteins and therefore have similar characteristics.