I'm generally favorable to technology, but as my mother used to observe, there were advantages to animals. For example, when field work for the day was over, you could pretty much let the team of horses find their way to the barn. And, according to her though I never experienced it, if you took a load of potatoes from her folks' farm to the city (Binghamton) to sell, once the load was disposed of the horses would take you home with little or no guidance.
I'm reminded of that when I read a recent post on Ricks' "The Best Defense". Earlier I'd seen the progress people were making on developing a pack robot, four-footed, self-powered, capable of crossing irregular terrain carrying 1-200 pounds. It looked impressive. Then there was Sgt. Reckless, a war horse in the Korean War, who carried 5 tons in 51 trips. I bet she was a lot quieter and a lot cheaper to develop.