You have heard the old consolation to spurned suitors: "Remember, there are other fish in the sea." Well, as it turns out, that is far truer than anyone had imagined, especially if you consider not just fish, but all different sorts of life forms, including bacteria.

About 2,000 scientists from 80 countries have gone on hundreds of voyages over the past decade in an effort to compile on Census of Marine Life, a comprehensive catalog the oceans' + char(39)+ N' + char(39)+ N' + char(39)+ N' biological diversity. In the past, scientists estimated that there might be more than one million species in the oceans, some 230,000 of which had not yet been identified. Those estimates are still listed on the census web site, which apparently needs to be updated. According to a newly-issued press release, census research now indicates that there may be more than 20 times than number of bacteria species alone, and that the total number of species of marine microbes of all sorts may be close to one billion.

"There are many more species than we thought there were," Dr Ann Bucklin, head of the University of Connecticut Marine Sciences Department, said in an article in the Times, a UK newspaper. "It turns out the ocean food web is much more complex than we thought it was, in terms of the number of different species."

You may think that oceans" smallest life forms--tiny microbes, zooplankton, larvae and burrowers in the ocean bed--aren' + char(39)+ N' + char(39)+ N' + char(39)+ N't as big of a deal as, say, the estimated 4,000 species of fish that scientists believe have not yet been discovered. Guess again. Such creatures amount to somewhere between 50 and 90 percent of the oceans" total biomass, according to scientists. They now estimate, based on samples taken from 1,200 ocean sites worldwide, that the number of microbial cells in the oceans' + char(39)+ N' + char(39)+ N' + char(39)+ N' waters is roughly one nonillion. That is a 1 with 30 zeroes after it. It is the equivalent of 240 billion 9,000-pound African elephants. Scientists now estimate that there may be as many as a billion individual organisms in each liter of seawater or gram of seabed mud.

That population of tiny creatures is also incredibly diverse, researchers have found. During a single 11 month period in 2007, the census researchers sequenced the genes of more than 180,000 bacterial specimens taken from the oceans, and found that one in every 25 readings yielded a previously undiscovered genus -- that is, a group of species.

These miniscule creatures also are incredibly important to the planet. They are responsible for 95 percent of the ocean"s respiration. By turning atmospheric carbon dioxide absorbed by the ocean back into carbon to be sunk to the depths (and doing likewise with nitrogen, sulfur, iron, manganese and more), marine microbes regulate the composition of Earth"s atmosphere, influence climate, recycle nutrients, and decompose pollutants.

Some of the most astonishing discoveries have been made in deep water. In the eastern south Pacific, for example, researchers have found bizarre giant, filamentous, multicellular bacteria that utilize hydrogen sulfide. The latter may essentially be living fossils, dating back to the early oceans 2.5 billion to 600 million years ago, when there was little oxygen.