Microbial Diversity-I: The Kingdoms and
The Domains (Status of Microorganisms in Biological World)

Microbial diversity

refers to the variability among micro-organisms within species, between species and of microbial ecosystems. It actually- evolved as a part of the organisms' evolution and the smallest unit of microbial diversity is the 'species'.

Attempts to estimate the total number of micro-organisms on the earth is a difficult work due to variety of problems; detection in and recovery from the environment, incomplete knowledge of microbial associations, etc. are few such problems.

At present, latest technique such as DNA-DNA hybridization, nucleic acid fingerprinting and methods of assessing the outcome of DNA probing and perhaps most important one, the rRNA sequencing are being used by the microbiologists to uncurtain the diversity among micro-organisms.