“I can tell you the exact date that I began to think of myself in the first-person plural — as a superorganism, that is, rather than a plain old individual human being. It happened on March 7. That’s when I opened my e-mail to find a huge, processor-choking file of charts and raw data from a laboratory located at the BioFrontiers Institute at the University of Colorado, Boulder. As part of a new citizen-science initiative called the American Gut project, the lab sequenced my microbiome — that is, the genes not of “me,” exactly, but of the several hundred microbial species with whom I share this body. These bacteria, which number around 100 trillion, are living (and dying) right now on the surface of my skin, on my tongue and deep in the coils of my intestines, where the largest contingent of them will be found, a pound or two of microbes together forming a vast, largely uncharted interior wilderness that scientists are just beginning to map.
I clicked open a file called Taxa Tables, and a colorful bar chart popped up on my screen. Each bar represented a sample taken (with a swab) from my skin, mouth and feces. For purposes of comparison, these were juxtaposed with bars representing the microbiomes of about 100 “average” Americans previously sequenced.
Here were the names of the hundreds of bacterial species that call me home. In sheer numbers, these microbes and their genes dwarf us. It turns out that we are only 10 percent human: for every human cell that is intrinsic to our body, there are about 10 resident microbes — including commensals (generally harmless freeloaders) and mutualists (favor traders) and, in only a tiny number of cases, pathogens. To the extent that we are bearers of genetic information, more than 99 percent of it is microbial. And it appears increasingly likely that this “second genome,” as it is sometimes called, exerts an influence on our health as great and possibly even greater than the genes we inherit from our parents. But while your inherited genes are more or less fixed, it may be possible to reshape, even cultivate, your second genome….”
“Humans are Just Biomechanical Suit Cities for Bacteria”
Food guru Michael Pollan has picked up on the “we’re more bacteria than human” meme and written an long, impressive New York Times article about it. He doesn’t go so far as to bring up the theory that oil is actually the excrement of bacteria that live beneath the earth’s crust, not the decomposed organic matter from the surface, as suggested by Thomas Gold (and apparently some unnamed Russians). If Gould is right then humans not just city-suits for bacteria, but also a waste disposal system for bacteria. This idea led Reza Negarestani to obliquely postulate that global warming will actually function to make the surface of the earth hot enough for those particular bacteria to live on the surface of the earth as well. Which means we’re doing, like, triple duty for our bacterial masters….”