Well it would be farsical to think that 10,000 years ago farming was an instantaneous success across the world.

Agriculture EVOLVED . Developing tools, planting techniques, storage of seed, selection and development of larger seeds, or larger roots. Takes generations.

Think about a carrot. Pull up Queen's Ann Lace and bite the root. Its a long 3-4 inch pencil lead thick orangy root. It is a wild carrot. A far cry fron the modern varieies that can weigh nearly a pound.

Somehow science, or is it people, requires absolutes. Concrete dates cannot be rigid because of an evolutionary process. For general purposes, dividing evolution into neat pockets makes learning and understanding history easier. Absolutes cannot be literally applied to agricutural development. Hence, 10,000 years ago was a noteable change to adding the "culture "of plants for our human use in a significant way. In the years prior, it was developing. Just as hunting and gathering continued on , side by side agriculture,, until modern times when it has nearly petered out.