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Many babies would be born since people could not stop pregnancies and wanted big families. But lots of babies and people would die because there were no good doctors, clean water, or ways to keep germs away.

Without shots, medicine, and good doctors, many more people would get very sick and die from diseases that spread quickly. This kept the number of people smaller in the past since lots of people died from being sick.

People could only grow food in small farms and hunt animals for meat. When food ran out, many would starve or not get enough to eat. The number of people would go up and down based on whether there was enough food.