Natural - Classification systems

• originally, Linnaeus' system relied purely on human judgement in order to compare the characteristics of various organisms. technological advances in biological equipment have allowed the current classification system to be developed.
• Three key advances that help the classification system to develop are:

  • use of microscopes
  • studies of biochemistry ( studying similarities/differences in amino acid sequences.)
  • DNA evidence (studying similarities/differences in DNA base sequence.)
• The use of microscopes has helped us to see more detail about cells and tissues which allows scientists to make comparisons between different species. This is important because it helps them to identify similarities and differences between species.
• Phylogenetics is the study of how related organisms are.
• Phylogenetics helps us work out how species have evolved from one another.
• Molecular Phylogenetics focuses on comparing the molecules (DNA and proteins) inside organisms to see how similar they are. the more similar the molecules, the more closely related the species. this is referred to as natural classification
• Natural classification is a biological method of grouping organisms based on their evolutionary relationships and shared characteristics
• Comparing DNA sequences of different organisms has allowed the relationships of organisms to one another to be explored even further.
• Species that are more closely related are more likely to have fewer differences in the sequence of their DNA bases.