Deploying a surgery that lets people eat grass

Question

Suppose some brilliant scientists devise a surgical operation which allows a human to eat, digest, and gain nutrients from grass, leaves, and all those indigestible plants. The operation costs $1000 USD. What is the best way to utilize this technology for the betterment of humanity?

Clearly the surgery should be promoted as a potential solution to world hunger. Governments would move money around and give the operation to anyone on food stamps or welfare within their own country (financially it's like an investment in reducing future taxes, so even from a purely economic perspective this makes sense), then start throwing money and surgeons into the third world.

I foresee tons of problems with this plan such as getting diseases from the grass, rapid stripping and exhaustion of plants, and people considering eating grass degrading. People in desert or icy climates wouldn't really benefit, which is a big problem. Furthermore, it's quite possible that governments, even those of pretty free countries, would ban cosmetic surgery, draft people into medical school, and in general limit freedom for humanitarian purposes, potentially causing unrest / who knows what. Then you've got your crazies who go sprinkling poison on all the grass, maybe lawsuits because your neighbor ate your grass and got sick, and a whole mess of problems basically.

Alternatively, the governments might take a slower, steadier approach, developing human-friendly, disease-free, hardy grasses and planting edible prairies all over the place and then very slowly, methodically applying the surgery to world hunger once a good framework was in place. However this could cause resentment or even revolt in starving people who think the powers that be are withholding the cure they need.

What is the best way to apply this surgery to bettering the world?

Answer 1

Making the poor people eat grass is unlikely to go well as such a forced procedure will be very unpopular. All it will take to sink the plan in a community is for someone to point out that the rich people aren't getting the surgery. Further, the comparison between poor people as herbivorous prey and rich people as carnivorous predators is also not far away.

Biologically, being able to digest cellulose will have huge implications on humans biology. Plants that we couldn't eat before we can now and this brings a huge increase in the plant toxins the human body will need to deal with.

This isn't a small change and the degree of resistance to it may be unprecedented in scope and fury.

Answer 2

Humans generally need an acre of productive farmland to grow enough to survive (on average), so in one sense this wouldn't change much; rather than an acre of rice or wheat, you would need an acre of pasture. In general terms this would be somewhat cheaper than farming on an individual basis (a "free range human" would not need to invest in plows, seeds, fertilizer, irrigation etc.), but on the other hand, the cost of land will skyrocket as the amount of available pasture land is limited.

Other forms of agriculture will also be squeezed as pasture is diverted from ranching or animal husbandry to direct human consumption. It is amusing to think that places like New Zealand will change in composition to where humans outnumber sheep...

Outside of the social issues mentioned by Green, you should also note that grazing is relatively inefficient from an energy production POV. Farming is much more efficient because we have spent the last 5000+ years breeding plants to become more efficient at concentrating nutrients in seeds, fruits and in other ways, as well as working out how to grow them much more efficiently. A "free range human" can probably survive on an acre of grass, but it will be a pretty marginal existence. Cattle and other grazing animals typically spend the vast majority of their time grazing, simply to extract the nutrients from grass, and your free range human will be doing the same, rather than engaging in productive work in the economy (unless "mowing the grass" counts).

One final point; any surgical intervention to allow humans to eat grass will be very extensive and probably cost more than $1000. The teeth need to be replaced by grinding molars which are hard enough to sustain abrasion by both the tough fibbers of the grass and sand particles caught in the grass. As well, since cellulose is pretty indigestible, either a crop will be needed (swallow some stones so the action of the crop can break up the grass), or the free range human will need multiple stomaches like a cow. A replacement of the intestines and a full reload of gut bacteria capable of digesting cellulose is also needed. After all that, the limbs could probably be modified too to allow for a comfortable 4 legged stance to make eating grass easier. Some modifications to the neck, and possibly making the jaw line longer to project from the face and allow easier access to grass and we are done.