Guns, Germs and Steel

Premise : When humans started agriculture, different species of plants adapted in various ways to make use of agriculture.

1. More than usual produce :

Some plants, like wheat started producing bigger seeds than usual so that humans would select them.

2. Losing the protection :

Seeds like almond which in wild could be poisonous and bitter, turned sweet and edible so that humans can harvest them.

3. A step in the opposite :

In the wild, pods are designed to burst open after ripening, to disperse easily. However, the ones that didn't burst, were chosen by humans as food and cultivated.

Premise : In the book "Anna Karenina" it is stated that 'Happy families are all alike;every unhappy family is unhappy in its own way.

J. Diamond uses this analogy to suggest why some species were domesticated and others not.

1. Elephants were seemingly rejected because of the gestation period. It becomes difficult to ramp up breeding such a species.

2. Zebras are not easy to be roped or tamed, along with their nasty attacking habits. Thus though they are close to donkeys and horses, they aren't domesticated.

3. Gazzele and antelopes due to their panicking nature and irregular social structure.