Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Conflict about classifying Protist?

  1. Dec 1, 2009 #1
    I was surpriesed to see that several information about protist is not consistent. Lets take a look.

    According to my biology lecture note:
    If it isn't anything, it is a protist:
    Kingdom protists
    -not a clade
    -not a legitimate taxon

    According to the wikipedia

    There is still lot of conflict whether protist is a kingdom or domain.

    According to an expert(annonymous):

    Domain: Eukaryota
    Kingdom: Chromalveolata
    Superphylum: Alveolata
    Phylum: Apicomplexa
    excavata, chromalveolata, Rhizaria is kingdom.


    What do you think? Everyone has different opinion how the protist should be classified. What should be preferred theses days? i.e., which one is more trustworthy?
  2. jcsd
  3. Dec 4, 2009 #2
    Previously, the highest category of classification of organisms was kingdom. There 'were' five kingdoms: animals, plants, protists, bacteria and fungi. However, this classification was primarily based on things like morphology and when the molecular geneticists looked at it they discovered that these where not supported by the data. The new highest category became domain and the domains are Eukaryota, Archeae and Bacteria (sometimes called Eubacteria to avoid confusing it with the every day term "bacteria", which applies to archeae and bacteria). This was done in an effort to make systematics adhere to the principles of cladistics. Protista is an informal term for a loose grouping of various different phyla that does not fulfill the criteria for a clade (it is paraphyletic). It refers to solitary or undifferentiated colonial eukaryotes. More research is needed to fit these various phyla into monophyletic groups satisfying the criteria for a clade.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook