From "Fundamentals of Economics........"

In a Hunter/Gatherer Economy there is not much need for keeping track of things. Animals are hunted and eaten, seeds, herbs and roots are gathered and eaten. There are products produced such as preserved food, weapons, clothes and huts but nothing very permanent. Counting is not very important and consequently you occasionally find these cultures with only three numbers – one, two, and “more than two”. I guess it’s hard to eat more than two mammoths or if one has to walk more than two days, it is not worth going there.