He claims that since Africans and Amerindians were happy to adopt Eurasian domesticated animals when they became available, it must be that that suitable local animals just didn’t exist. But that’s a non sequitur: making use of an already-domesticated species is not at all the same thing as the original act of domestication. That’s like equating using a cell phone with inventing one. He also says that people have had only mixed success in recent domestication attempts – but the big problem there is that a newly domesticated species doesn’t just have to be good, it has to be better than already-existing domestic animals.
Indian elephants, although not truly domesticated, are routinely tamed and used for work in Southern Asia. The locals in Sub-Saharan Africa seem never to have done this with African elephants – but it is possible. The Belgians, in the Congo, hired Indian mahouts to tame African elephants, with success. It’s still done in the Congo, on a very limited scale, and elephants have recently been tamed in other parts of sub-Saharan Africa, such as the Okavango delta. Elephants have long generations, which makes true domestication difficult, but people have made domestication attempts with eland, African buffalo, and oryx. They’re all tameable, and eland have actually been domesticated to some extent. ...
It's not exactly a secret that Africa invaded Europe on the backs of elephants in 218 BC under Hannibal of Carthage. Of course, those weren't unusable African elephants, those were useful North African elephants, which, conveniently enough, are said to be extinct. But, obviously, Hannibal's elephants must have been fundamentally genetically different from current African elephants, which proved so useless to sub-Saharan Africans. If only elephants with the right kind of genes had existed in sub-Saharan Africa, then sub-Saharans might have conquered Europe, instead of the other way around.
In fact, in my mind the real question is not why various peoples didn’t domesticate animals that we know were domesticable, but rather how anyone ever managed to domesticate the aurochs. At least twice. Imagine a longhorn on roids: they were big and aggressive, favorites in the Roman arena.