In, I think, the third episode the narrator pointed to some holes in the ground and commented that how our ancestor viewed those holes marked a huge departure from how every other animal on earth viewed those holes. See, those holes were tracks, prints in the dry soil left by some animal. No other animals sees them as such but we humans sure do. And, he went on, we (then and now) know which clouds for tell rain and understand the turn of the seasons. And why do we?
Before I answer that I'd like to add that to date, most of what I've seen in books in regards to the beginning of math seems to involve a picture of an ancient African stick marked with notches for counting or a story about a shepherd needing to count his goats. The impression being that math began with counting.
But look at these prints in the snow:
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Why are those not just holes in the snow?
Maybe it's partly because they're a regular pattern. Maybe we can track the seasons because we understand the pattern.
And if we're talking patterns, aren't we talking math?
Now I'm not saying Homo erectus was capable of multiplication, just that mathematical thinking, if you can divorce math from counting, may have been around longer than Homo sapien and that mathematical thinking may be one of the fundamental things that first defined humans. As much as taming fire. As much as imagination.
Now I realize even as I type this that it's probably FAR from an original thought. It's just one of those personal epiphany things. I also realize Mr. Human Ancestor may have been relying on correlation with the tracks, seeing cat walk and seeing the prints left behind and putting two and two together...But then we're back to mathematical reasoning, aren't we? :D
Anyhow, probably the cough syrup talking but I thought I'd post it anyway.