Some say that the 21st century will be as noted for biology advances as the 20th century was for physics. Could be. I find the subject fascinating and it becomes ever clearer that there's a lot we don't know, and that we have only recently discovered the extent of our ignorance. We used to know more, before we learned a little.

Most of what we know about the biochemical diversity of microbes comes from the tiny fraction that submit to lab investigations. Not until scientists determined that they could use molecular sequences to identify species and determine their evolutionary heritage, or phylogeny, did it begin to become apparent just how diverse microbes are. We now know that microbes are the most widely distributed organisms on earth, having adapted to environments as diverse as boiling sulfur pits and the human gut. Accounting for half of the world's biomass, microbes provide essential ecosystem services by cycling the mineral nutrients that support life on earth. . .

The emerging field of environmental genomics (or metagenomics) aims to capture the full measure of microbial diversity by trading the lens of the microscope (and biochemistry) for the lens of genomics (and bioinformatics). By recovering communities of microbial genes where they live, environmental genomics avoids the need to culture uncooperative organisms. And by linking these data to details relating to sequence collection sites, such as pH, salinity, and water temperature, it sheds light on the biological processes encoded in the genes.

This is from a synopsis for a collection of articles from The J. Craig Venter Institute's Global Ocean Sampling Expedition in PLoS Biology. There is a lot of interesting reading there for those of us that follow this subject.

I've speculated before that this is an approach that might advance our understanding of soil. For example we have the terra preta mystery. Some have speculated that a key characteristic of those Amazonian soils is a unique population of bacteria, archaea and fungi. They suspect that one reason why this type of soil hasn't been replicated is that there are different microbes where the tests have been done. Could be.

Environmental genomics has to be more than just identifying microbial genes to be useful. The real issue is what do those genes do? The sooner we have the gene information the sooner the hard work of figuring out what they do can begin. Or maybe it has already begun and I just haven't heard about it? I can't wait, though I must.