Bacteria Everywhere (Biology Today) (Report‪)‬

It's about time that we stopped being surprised by bacteria. So many articles on these organisms express amazement that bacteria are found where no life was expected to be, or are unbelievably abundant, or have unforeseen capabilities. After so many shocks, shouldn't we have figured out that bacteria are truly wonderful and just expect to be flabbergasted? I was thrilled when I found out ABT was planning a themed issue on microbes, because this gave me a chance to write about my favorite organisms. However, the problem with bacteria is that there are so many of them, and they do so many astounding things, that it's hard to focus. I ended up deciding to go deep--deep into the earth and deep into the ocean--to see what the latest research has revealed. Needless to say I found some amazing things. Before I go further, I should say a word about terminology. The term "bacteria" used to refer to all prokaryotes, until the 1970s, when Carl Woese discovered that some bacteria were so genetically different from others that they really represent a different category of life, which he dubbed the "archaea" (Woese & Fox, 1977). These species tended to be found in extreme environments--high pressure, high temperature, or high salt content--but like most biological characterizations, this one isn't absolute. Archaea have been found to be more diverse and ubiquitous than originally thought. And they are so different genetically from bacteria that biologists now agree with Woese's once-outrageous suggestion that they be put in a separate domain. They are now considered as genetically different from bacteria as both are from eukaryotes, the members of the third domain of life forms. I will attempt to be true to the distinction between archaea and what are now termed "eubacteria," but this isn't always easy, because even in scientific publications the distinction isn't always made. If you think this makes things confusing, you can imagine the confusion it causes students.