An estimated 1,000,000 bacterial species exist on this planet, according to the Global Biodiversity Assessment, yet fewer than 4500 have been described. The greatest genetic diversity of life comes from within the world of microorganisms, yet the least is known about them.
Microbes inhabit the widest range of habitats from sub-freezing temperatures, to water hotter than boiling, from the rocks beneath our feet, to the atmosphere miles overhead, to the stuff between our toes, to the tops of mountains and to the deepest ocean trenches. For an introductory look at some diverse habitats that microbes call home, check out the Microbe Zoo web site at:
Hunting for new microbes is not as easy as taking a jeep trip in the outback with a pair of binoculars. By definition, microbes are invisible without the aid of a microscope, so the challenge to find new ones is great. The difficulty is compounded when one does look under the microscope to see two apparently similar bacteria which later prove to be not at all similar. For example: two bacteria may have the same rod shape, but one thrives in the presence of oxygen whereas the other one is killed by oxygen.
Because microbes are so difficult to observe, they are the last organisms to be catalogued with fewer than one percent yet described.
To see how microbes are related to other life forms, check out the Tree of Life web site at:
Heywood, V. H. (ed.) 1995. Global Biodiversity Assessment, p.1140. Cambridge University Press, Cambridge.
Microbial Biodiversity Working Group
The greatest diversity of life comes from within the world of microorganisms. To help sort out and understand this tremendous biodiversity, the Microbial Biodiversity Working Group was started.
The goals of the working groups are generally to assess the advances, opportunities and needs of the field, consider society activities such as workshops, summary publications or new articles that highlight microbial biodiversity, and provide advice to national and international groups on biodiversity.