The answer to this question can be found in Chapter 8, starting on p. 136 in the paperback edition of the book. There, Diamond tells us why the Fertile Crescent was better suited than most areas for developing agriculture. Because the region was good for agriculture, it was the first to develop in the ways you mention. The ways in which the Fertile Crescent was good for agriculture include:
- It has a "Mediterranean" climate which is idea for developing the kinds of plants most useful to people.
- It had many wild plants that could be domesticated quite easily.
- It had many plants that can pollinate themselves but which occasionally cross-pollinate with other plants. This was good for allowing farmers to experiment with breeding their plants while still allowing the good traits to continue from generation to generation.
- It has a great deal of variation in climate from year to year and season to season.
- It has many kinds of topography and different elevations in a relatively small area.
- There are lots of animals that can be domesticated.
- It was not very good territory for hunter-gatherers and so farming societies did not have to compete with them.