Why did the agricultural revolution begin?

The agricultural revolution is also known as the neolithic revolution. It started in a region of the middle east known as the fertile crescent and subsequently spread throughout the globe. Experts have different opinions on how this may have occurred. Some suggest cultural diffusion but others disagree. There is how ever a strong argument for a theory that suggests that farmers themselves migrated from the region and displaced existing hunter gatherer populations in Europe. So it started with invasion