Algae:
where they fit into the 8-Kingdom System
Not only is this scheme the most recently proposed, but also the most controversial. Its construction stresses that the term 'algae' wrongly tried to combine organisms with such diversity and differential evolutionary histories into a single group. Under the 8-Kingdom System, algal members are dispersed in vastly different kingdoms that are distinct from each other. Based on advanced genetic and ultrastructural studies, this system is generally supported by a handful of biologists who advocate the need to either elevate various algal members to a higher taxonomic status or to qualify them more distinctively. This has led to the reorganisation of many groups in such a way that their diagnostic characters suggest their evolutionary relationships to other groups more accurately.
The 8-Kingdom System was borne from the phylogenetic hypothesis that the Archaebacteria diverged from the main eubacterial lineage at an early stage at the dawn of life. The Eubacteria which contains the Cyanophyta, then evolved linearly and only much later formed the oldest member of the Eukaryota, the Superkingdom Archeozoa. This superkingdom in turn evolved in a 1-way fashion to give rise to Superkingdom Metakaryota, the most basal member being Kingdom Protozoa. Also contained within the Metakaryota, are the four highest eukaryotic kingdoms derived as four distinct individual lineages from the Protozoa, namely Kingdoms Plantae, Animalia, Fungi and Chromista.
For the phylogenetic tree representing the 8-kindom system, click here.
TREE