The sugars that the plants produce are traded with the fungi that inhabit the root systems. The return trade being the phosphorous necessary for the pant functioning and that sugar production. This is not a simple trade either, we see a price system in action. The phosphorous is preferentially moved and then traded to where it is in shortest supply, and so gains the trade of more sugar in return.
Observations of this wider world of life really do give us examples of the economic activity that we ourselves engage in. More than that, we see things which are regarded as controversial in human economic affairs, things that are still argued about. For there are those who insist that trade is something that must be limited — but if apes can grasp the concept then why can’t we?
We even have, in those plant roots, evidence of supply and demand curves in operation yet there are all too many who deride the price system among us humans. Or, as we might put it, if the bugs in the ground under our feet can grasp the basic elements of the Economics 101 class and the diagrams on the first page of the textbook, shouldn’t we demand that our politicians at least attempt to do the same?