It's a good question, MTG. I will assume by "natural language NL", you mean French, Chinese, ... . Well, I think there are two different forms of com to NL; 1an artificial one like maths, programming, logic,... and 2coms as signs of regularity; one sees the leaves fall; one knows it is Autumn. One feels the cold; one needs warmer clothes, one sees a tiger; one needs to grunt for your friends, etc etc.

2 and the grunts probably began NL, where NL words became useful and, most importantly, quicker than the feelings/signs. Later on, 1 came about, at a higher level of abstraction than NL, NL, having arisen unconsciously and gradually, while 1 came purposefully and faster. Perhaps, in the future, there will be someting even more abstract that can explain, or talk on a higher level than, 1. Personally, I find this hard to imagine. Anyway, this is just my opinion.