Unless the Humans attempted to develop machines to replace the functions of the plants.
That is exactly the point, there is no such technology (which we have invented) which already doesn't exist in nature. In fact, it exists in nature at a far superior level. There is infinitely superior technology even within a blade of grass. What we do is just emulate the technology in nature on a human scale(large) but in a very crude form. For example human body converts a variety of food into energy and we convert some crude forms(crude oil) in a very inefficient way. We all were once part of a ball of fire(lava).
Invention is nothing but discovering nature's technology and replicating it in a crude form on a human(larger size) scale. Infinitely superior technology already exists in the tiniest of particles. He who thinks we are technologically advanced is nothing but an Ignorant idiot.
May be you can patent - triple mouse clicks to open porn.
The flush toilet is the basis of Western civilization. -- Alan Coult