I haven't had time to read it totally, but I have to disagree with the first article you have posted in your essay.
Chewing the cud is not an idle passtime. It is a very well thought out mechanism.
The rabbit, hare, and cows and a lot of other grass eaters, quickly eat grass at one spot, so they have their stomach full.
It is all about speed, because if you're in the open too long, you might get caught by a predator.
So they eat it without chewing it.
But after having eaten it, they return back to a safe spot, and there they cough it up again, to have it digested properly.
You see, grass and plants are very difficult to digest. It needs chewing to mash it up and that it can mix with the saliva of the animal so that the breakdown process of the cell wall can be started. Plant cell walls are very tough, and they need this process of breakdown, because otherwise they won't break down, which leaves the food useless.
And since this article is wrong, and your essay might continue on this article... well, I don't bother
Michael