Classification system

• Carl Linnaeus proposed a new type of classification, the Linnaean system, which groups species together according to their characteristics and bone structures.
• The Linnaean system groups species into kingdoms such as plant or animal, then phylum, class, order, family, genus, and species.
• Carl Linnaeus also proposed the binomial naming system where species are named by their genus and species names.
• In the 1990s, Carl Woese proposed the three domain system using evidence from new techniques that could analyze rna sequences.
• The three domain system adds three new categories called domains above kingdoms: Eukaryota, which contains all the organisms that have eukaryotic cells similar to ours such as plants, fungi, protists, and other animals; Bacteria, which refers to the very tiny single-celled prokaryotic organisms that are found almost everywhere; and Archaea, which were originally thought to be bacteria but are actually a different type of prokaryotic cell which are often found in extreme conditions like hot springs and salt lakes.
• Evolutionary trees show us the evolutionary relationships between different species or groups by linking common ancestors.
• Different evolutionary trees can look quite different, but the main thing to remember is that whenever a line splits in two it's because a common ancestor is splitting into two different species.
• Scientists had to compare the structure and dna of different species, including fossil records, to learn all these relationships.
• The best strategy to remember the order of all these groups is to find a good mnemonic, which is a phrase used to help remember terms in a list.