The Bible verse, Gen 10:25, could mean that the region was divided up (for personal ownership) rather than communal ownership. It might also refer to city states each owning part of the land so the whole region was owned. Saying the continents were joined together and were separated is just an interpretation. They insist that their interpretation is right and then use it to prove their point.
In fact, it wasn't until after ~2,500 BC that the city states grew big enough that their borders ran into each other and there was no more arable land in Sumer.
Adminnemooseus says - An interesting point for a different topic, but pretty damn far from this topic's theme. Maybe a
new topic?
Edited by Adminnemooseus, : Off-topic banner etc.