Final answer:
The Neolithic period was marked by the critical transition from the nomadic hunting and gathering lifestyle to settled agriculture, known as the Neolithic Revolution, resulting in profound societal transformations.
Step-by-step explanation:
The major shift that occurred during the Neolithic period was the transition from a nomadic lifestyle of hunting and gathering to a settled agricultural lifestyle, which is termed the Neolithic Revolution. This profound transformation allowed human societies to cultivate and domesticate plants and animals, leading to a rise in stable food supplies, population growth, and the establishment of complex societies.
Evidence of these changes is found in Neolithic settlements like Çatalhöyük, with its elaborate room decorations and architecture designed for protection, and the sophisticated early communal efforts exemplified by constructions such as Göbekli Tepe. The shift ushered in new social structures, economic practices, and even modified religious traditions.