Re #2, it's tolerance to an extremely awesome herbicide. Glyphosate is extremely toxic to plants and extremely non-toxic to everything else. Doesn't kill mammals or insects, doesn't migrate to the water table (it binds to soil and then breaks down when unbinding), doesn't cause cancer. There's a reason farmers love it, especially the ones who remember all the toxic, carcinogenic chemicals they used in the 50's and 60's.