Meta_Organism: The Human Federation.

I remember reading a book that had been with me for close to two decades some 7 or 8 years ago. The book was by a Russian (or rather Soviet – Mir Publishing ) Immunologist – R V Petrov –  and was intriguingly called *Me, or Not Me*. In fact, it was the simplest way of explaining immune system’s first task, which is to make a decision every moment if a particular cell or molecule is part of Me or an Enemy. Petrov in it had delved upon the view of Human body as a kind of federation of groups of individual cells, which have come together to cooperate because they discovered their chances of survival improve multi-fold by forming a federation rather than if they were to do it separately and alone. Though foregoing smacks of *volition*, what it dramatizes is the fact that cooperation enjoyed evolutionary success, which eluded loners. He had given examples of earlier independent organisms, who had adapted to, adopted and become part of the whole. This has echoes in Richard Dawkins’ book, The Selfish Gene. The author later felt that another title suggested to him by a friend, The Immortal Gene, better captures the spirit of the Book: Dawkins did not wish to imply by the word *selfish* any *motive* to the gene, but felt that the consequences of gene coding were such as to implicate  *behaviour* driven by *self interest*. ^^The contention here is that the genes that get passed on are the ones whose consequences serve their own implicit interests (to continue being replicated), and not necessarily those of the organism, much less any larger level ^^.  I had then imagined Humans as a kind of Meta-Organisms, who are in turn a cooperative of other organisms. Such view has recently gone mainstream as can be seen in this article from The Economist: Microbes Maketh the Man.
Some 23000 genes code and fabricate a collection of specialised cell groups, which together add up to 10 trillion cells. But that is not all. There are some 100 trillion cells residing in our body and even on it (skin) that are coded and fabricated by some 3 million genes that are not part of Human genome. Yet, these are crucial to the very survival of the Meta-Organism, or what Economist calls Super Organism. Petrov’s description was confined to the Human Organism as coded and fabricated by 23000 genes. Now, it is getting extended beyond the original remit. These 100 trillion cells -collectively called microbiome- are not free passengers or parasites, but are contributing members of the common wealth, whose presence is vital to the 10 trillion human cells. Another noteworthy feature is that microbiome of every individual is unique; as unique as the individual is. 

The microbiome does many jobs in exchange for the raw materials and shelter its host provides. One is to feed people more than 10% of their daily calories. These are derived from plant carbohydrates that human enzymes are unable to break down. And not just plant carbohydrates. Mother’s milk contains carbohydrates called glycans which human enzymes cannot digest, but bacterial ones can. This alone shows how closely host and microbiome have co-evolved over the years. But digestion is not the only nutritional service provided. The microbiome also makes vitamins, notably B2, B12 and folic acid. It is, moreover, capable of adjusting its output to its host’s needs and diet. The microbiomes of babies make more folic acid than do those of adults. And microbiomes in vitamin-hungry places like Malawi and rural Venezuela turn out more of these chemicals than do those in the guts of North Americans.

The microbiome, it seems, fabricate molecules that regulate and keep in check the activities of human cells. Any disturbance of this function, the new perspective gaining ground suggests, leads to several disease conditions. This is going to impact profoundly how the future antibiotics or let us say Co-biotics (Cooperative Biotics) will evolve and also expand the *gene-field* that geneticists currently mine to find clues of hereditary links to diseases. ^^Many of the diseases in which the microbiome is implicated seem to run in families. In some, such as heart disease, that is partly explained by known human genes. In a lot, though, most notably autism, the genetic link is obscure. This may be because geneticists have been looking at the wrong set of genes—the 23,000 rather than the 3m. For those 3m are still inherited. They are largely picked up from your mother during the messy process of birth^^.
The discussion though confined to Humans is true in case of other Meta-Organisms as well. Cow for example is incapable of digesting the grass on her own. There are bacteria in her stomach that actually breakdown the mulch into ingredients on which the bacteria feed in frenzy and replicate in abundance. It is this *soup*,  rich in bacteria, that the Cow digests to derive her  nourishment. Cow is not vegetarian after all at least in the *digestive* sense.  

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