"The Clever Hans Effect has also been observed in drug sniffing dogs. A study at University of California Davis revealed that cues can be telegraphed by the handler to the dogs, resulting in false positives."
Right. And $1,000 spent on bullets has the same ROI as building schools.
"Those cattle occupy the same ecological niche as the bison did 150 years ago, with a similar environmental impact. Tearing up the native prairie to grow any sort of grain or vegetable crop would destroy the land."
No. Bison bite off the grass, leaving the roots. Unlike cattle. Some argue that bison were an important part of the ecosystem.
There's been modern experimentation with "intensive grazing" to emulate what the early bison herds did to grasslands. Densely packed cattle are moved using temporary electric fence over smaller areas of pasture for shorter amounts of time. The end result is quality feed for the cows, the manure gets trampled into fields, helping water retention and fertility, and the cows are moved along before they completely destroy the area.
Joel Salatin, of Polyface Farms here in Virginia, uses this practice to good success.
I don't know if such practices can sustain the volumes of cheap beef production we enjoy now, but if we properly managed large grazing areas this way, we could utilize land/water/feed much more efficiently than we do now.