Phospholipid-derived fatty acids microbial classes when in fact those PLFAs are present in a broad range of life forms. Phospholipids can occur in many biological classes (such as in plant roots, fungi, as well as in soil bacteria), so care has to be taken in over-assigning PLFA biomarkers to the wrong class. Even though phospholipids occur in many different life forms, the fatty acid side chains between differing life forms can be quite unique. Polyunsaturated fatty acids ("e.g." 18:3 ω3c) are found in plants, algae and cyanobacteria, but are often not present in bacteria. Monounsaturated fatty acids (particularly at the omega-7 position), odd-chain
Cavalier-Smith's system of classification scheme they reintroduced the classification with the division of prokaryotes superkingdom into two kingdoms, Bacteria (=Eubacteria) and Archaea (=Archaebacteria). This is based on the consensus in the Taxonomic Outline of Bacteria and Archaea (TOBA) and the Catalogue of Life. Cavalier-Smith's system of classification The classification system of life introduced by British zoologist Thomas Cavalier-Smith involves systematic arrangements of all life forms on earth. Following and improving the classification systems introduced by Carl Linnaeus, Ernst Haeckel, Robert Whittaker, and Carl Woese, Cavalier-Smith's classification attempts to incorporate the latest developments in taxonomy. His classification has been a major foundation in modern taxonomy,