I believe that you are asking which animals, or which kinds of animals, Diamond says that you would not want to domesticate. If this is so, the answer is to be found in Chapter 9 of Guns, Germs, and Steel.
In Chapter 9, Diamond lays out all the ways in which certain kinds of animals can be bad for domesticating. He argues that there are a number of criteria that have to be met before an animal can be a good candidate for domestication. Any animal that fails any one of the criteria is one that you do not want to try to domesticate. Let us look at these criteria.
- Don’t try to domesticate a carnivore. Carnivores need to eat too much in order to get big. It would be very hard to supply a carnivore with all the food it needs to grow to a useful size.
- Don’t domesticate animals that grow slowly. You will have to feed them for a long time before they are big enough to be useful.
- Don’t domesticate animals that don’t breed well in captivity. If they do not breed well, you do not get successive generations of domesticated animals.
- Don’t domesticate animals that are too aggressive. Animals like African buffalo are simply too aggressive by nature. This makes them dangerous to try to domesticate.
- Don’t domesticate animals that panic easily. They are too likely to run away or to die of fright.
- Only domesticate animals that live in herds with hierarchies. These animals tend to stay together and they tend to accept humans as the dominant member of their hierarchy. These things make them easier to keep.
If you were a hunter-gatherer, Diamond says you would need to follow these rules in picking which animals to domesticate and which to leave alone.