Two reasons why a civilization fall

From the collapse of ancient Rome to the fall of the Mayan empire, evidence from archaeology suggests that five factors have almost invariably been involved in the loss of civilizations: uncontrollable population movements; new epidemic diseases; failing states leading to increased warfare; collapse of trade routes ..

Explanation:

source- www.weforum.org

a standing committee

explanation:

the group i'm selecting: greeks.

a first group of greek immigrants came to the us in the 1850s. the second group came to america starting in the 1890s due to economic opportunities they didn't have back in their home caused by the hardships of ottoman rule. greek immigration was 90% male, many of them expected to work and return to greece after earning enough capital, but ultimately had to remain in the us after the greek genocide.