Question

what could be the reasons behind the statement the advent of agriculture marked a significant change in the Neolithic stage

Answer 1

If I am understanding your question correctly, there are several reasons why agriculture marked a huge turning point. First off, prior to agriculture, gender divisions were less. Women had respectable roles, as did men. However, with agriculture came social class divisions as seen in almost every society, as well as severe gender and racial divisions. Next, agriculture finally was able to sustain larger communities living in close proximity to each other. As a result, population grew larger than ever before. However, this also allowed for the world's first every epi/pandemics. Therefore, the development of agriculture marked so many new events and ways of life, that it made a new era; the neolithic era. I hope this helps! :)