Imagine that you are shepherding your families flock of sheep, way back in pre-history. Your Dad would like to know each evening, that you have brought back as many sheep as you started out with in the morning.
So the short answer is in unrecorded pre-history.
Our present European number systems have their origins in the Middle East.
But the Chinese and the Maya (at least) independently invented number systems.
So the need for a number system seems to have driven its invention.
"Necessity is the mother of invention" as the saying goes.
God
Their are two types of number systems. 1. Non positional number systems 2. Positional number systems.
The wheel came into existence by the early men. -they used diagrams of circular objects like a potters wheel to come up with the WHEEL!!!!!!
God spoke the universe into existence. See the first chapter of Genesis.
why are the number of plant systems smaller than animal systems.