How abundant are bacteria in terms of biomass?

Doug Eernisse DEernisse at
Tue Feb 28 12:59:50 EST 1995

I previously wrote:

@ > Sure, there are lots more bacterial cells out there than
@ > eukaryotic cells, but how do they stack up relative to
@ > important organisms such as diatoms, dinoflagellates, copepods,
@ > etc., in terms of total biomass on Earth? Have there been
@ > any estimates broken down according to the extant phylogenetic 
@ > groups of bacteria?

and Richard Heath responded:

> Are you suggesting that bacteria aren't important???
> (don't know the answer to your question though, sorry)

Nope. I have read that diatoms (the most abundant phytoplankton
organisms) produce more oxygen and have greater biomass than all 
land plants combined. That seems important to me. Copepod biomass
dwarfs that of any other animal's biomass. Ditto. I have read
that there are more bacterial cells than eukaryotic cells. So
how much total biomass do bacterial cells account for. I have
no clue.

Sure, there are bacteria that could whip a polar bear (oops, sorry,
wrong thread 8^).


Doug Eernisse <DEernisse at>
Dept. Biological Science MH282
California State University
Fullerton, CA 92634

More information about the Bioforum mailing list