tomatohorse

If I read the OP's idea correctly, major modification of the digestive tract would not be necessary because we would be using our already existing bacteria.... just modifying their DNA so that they can also digest cellulose. It's not like we'd be introducing a whole new species of bacteria into our guts. Same species, just with an extra strand of DNA that lets them digest cellulose. I think this idea is intriguing... can't believe it's never been tried. Or has it and we just don't know about it? Why would we need to seek nutrients elsewhere? I don't see where we'd be lacking amino acids by adding capability to our digestive bacteria...