linnaeus class classify class of all organisms organisms into two kingdoms later sciences added a third kingdom later still scientist expanded the system to five kingdoms now scientist classify organisms into 3 domains which are divided into 6 kingdoms what is the reason for these changes ?
https://www.sciencelearn.org.nz/resources/1438-classification-system
The reason for the changes in the classification system from Linnaeus's two kingdoms to the current system of three domains and six kingdoms is due to advancements in scientific knowledge and understanding of the complexity and diversity of organisms.
When Linnaeus initially classified organisms in the 18th century, he grouped them into two kingdoms: Plantae (plants) and Animalia (animals), based on their observable characteristics. However, as scientific techniques and tools improved and more information became available, it became clear that this two-kingdom classification was insufficient to account for the full range of life forms.
Later, in the 19th century, scientists added a third kingdom called Protista to encompass microorganisms and eukaryotic organisms that did not fit neatly into either the Plantae or Animalia categories.
As scientific understanding further expanded, it was recognized that there were fundamental differences not only between plants, animals, and protists, but also among microorganisms. This led to the development of the five-kingdom system, proposed by Robert Whittaker in 1969. The five kingdoms included Monera (bacteria), Protista (eukaryotic microorganisms), Fungi (fungi), Plantae (plants), and Animalia (animals).
However, it was later discovered that the differences between certain microorganisms and other organisms were so profound that they warranted a higher taxonomic rank. This led to the introduction of the concept of domains in the 1970s by Carl Woese. The three domains are Archaea, Bacteria, and Eukarya, with Archaea and Bacteria encompassing prokaryotic organisms, and Eukarya including all eukaryotic organisms.
Under these three domains, the six kingdoms are now classified as Archaea (archaea), Bacteria (bacteria), Protista (eukaryotic microorganisms), Fungi (fungi), Plantae (plants), and Animalia (animals).
The reason for these changes in the classification system is to make it more accurate and reflective of the evolutionary relationships and biological diversity seen in the natural world. As scientists continue to study and discover new forms of life, the classification system may continue to evolve to better capture the complexity and relationships among organisms.