I disagree with Guns, Germs and Steel. Diamond makes lots of claims that seem dubious to me. E.g. says zebras seem vastly harder to tame than horses. But you would have to compare against the early wild horses, obviously! We have no reason to think zebras are harder.

Wild animals in general are uncooperative and belligerent. And we actually have several cases of people "breaking in" and riding zebras! That's without even having hundreds of years of selective breeding. So this whole claim just seems like such obvious nonsense.

Doesn't even have many generations of selective breeding, and it's possible to train them very gradually. Even @cgpgrey repeated this false claim in one of his videos. Everyone is just repeating this gibberish that Jared Diamond made up.

He also asserts that American bison are hard to domesticate, and cows were easy (and then reasons that colonial-era Europeans were lucky). I'm sure they were lucky but not for such a silly reason. Again, the early wild cows were horrific, belligerent monsters.

Cows were domesticated from aurochs -- now-extinct wild cow-like animals. So were the aurochs relatively docile and cooperative, compared to American bison?

Not according to our written accounts of them. Here's Julius Caesar:

https://hydeandrugg.wordpress.com/2014/06/17/caesar-on-the-aurochs/

This seems consistent with other descriptions of the aurochs.

So Diamond just says "That's so lucky of Europeans to have cows!" And they were, but Diamond utterly misunderstands. He thinks bison are especially hard to domesticate, but there's no reason to think that at all.

By the way, I know Diamond's book is old now, so he didn't have Google and whatever data came out since.

But at least for the zebra thing, here's a bunch of old-timey photos of people doing all kinds of horse-like stuff with zebras:

http://messybeast.com/history/working.htm

Some people have pointed out that zebras social structure is less favorable, because they don't automatically follow the leader of the hierarchy. But this doesn't explain why they weren't domesticated at all, because they would still be extremely useful for other things!

To emphasize the point on the horses, people don't appreciate how much time and selection has gone into horses to make them useful. This is a large update against the idea that their wild ancestors were somehow specially wonderful. https://www.reuters.com/article/us-horses-history/horses-first-ridden-and-milked-5500-years-ago-idUSTRE5246HI20090305

Onto the plants. Researchers say potatoes were very important to fueling the expansion of the European empire.

Potatoes...which are from the New World continent.

They had potatoes all along, and Europe didn't. Until the Spaniards grabbed some.

https://bit.ly/2N2QMW1 

This seems like a big update against Diamond's thesis! The fabulously-productive potatoes were in the New World all along, and Europe's empire noticeably swelled *after* getting such a value source of calories, brought over from the New World continent!

Jared Diamond is highly influential. Yet the more I look into it, the more full of shit he seems.

I haven't mentioned the super bizarre claim he makes about the intelligence of Papua New Guineans. Diamond says “in mental ability, New Guineans are probably genetically superior to Westerners”. This is an astonishing lapse in understanding of modern intelligence research.

All the "wild" horses in the world aren't fully wild. And the ones that were actually wild are "almost impossible to ride".

https://www.amnh.org/explore/videos/biodiversity/wild-horse-mongolia/article-when-is-wild-actually-feral