The modern guitar is the product of thousands of years of evolution. The size, shape and construction of guitars has changed though history, but is this evolution now over?
The big idea in evolution is that in nature there are variations, some of these variants are more likely to survive (natural selection) and have their attributes are passed on to future generations. The same applies in guitar making. Guitars that play and sound the best are more likely to be popular and have their features incorporated into new models.