The correct answers are B) forming of organized government as the population increased and D) conversion of more land to productive fields.
<em>Two of the cultural similarities of early river valley civilizations were forming of organized government as the population increased and conversion of more land to productive fields.</em>
When humans stopped being Nomads and learned agriculture techniques to grow crops during the Neolithic Revolution or Agriculture Revolution, things change for civilizations. Ancient river civilizations settled in next to rivers for the importance of water and the many advantages it represented. For instance, the Sumerians established between the Tigris and Euphrates Rivers and the Egyptians next to the Nile River. These civilizations started to develop a more organized and formal type of government to rule social interactions such as trade. As they were perfecting agriculture techniques these civilizations were capable of converting more land to have better crops and productive fields.
