Time to shelter in caves again?

The news is nowadays so terrible that I was thinking about the future and the past again. What would it really be like if people would go back to a stone age situation? Over in Europe there's nothing much else than ice and virgin forestry. People were hunters and gatherings that were moving place to place. I've always wondered about that. How about if their journey wasn't that lineair each year?

How about that those stone age people actually rather going to the South of France in the winter and returning back to Denmark in the summer? How much privacy would they have then in those caves? How big a group was there necessary to provide all the necessities on the hoof? Plenty of questions that I'm posing this afternoon. Lets have a look if we can answer those.

During the European stone age most groups that utilized caves or rock shelters were small, mobile bands. Scientists generally estimate group sizes based on resource availability and social needs. Those were primarily small bands of twenty or thirty adults and children. Lets go through this. Women at the time have birth on average to about five to six children of which only two or three survived to adulthood.

The earliest hunter-gatherers in Europe had fewer kids, spacing births further apart due to the need to move frequently and keeping family sizes small. Morever, hunter-gatherer mothers had to carry infants, encouraging longer spacing between births, often up to 4 years. Stone age people were physically similar to modern humans but generally more robust, with powerful muscles due to a physically demanding, active hunter-gatherer lifestyle.

Average life expectancy then stayed low (often 20–35 years) due to high infant mortality, but adults who did survive childhood could live into their forties or older, with some reaching their sixties. Lets do the maths now. If the group is twenty in total then the composition could have been two couples of grandparents with four more couples bringing up eight infants. Am I right?