Farmers have been improving their crops for a long, long time.
You think maize has always consisted of big, sweet, juicy ears? You think apples have always been plump? Cotton got improved as well.
It's called Intelligent Design.
It’s called artificial selection.
It is not intelligent design nor is it natural selection and traditional punctuated evolution.
Cotton is a crop and the change in the makeup is the result of dedicated and smart farmers developing seed over long periods of time. Once a major breakthrough was obtained the intensive breeding effort waned.The fact there is similar cotton in the Orient , ie Egypt and most likely India as well, and the Occident points to cotton being migrated with the people coming out of Asia.
If you recall your Darwin, it was detailed studies of just such human selection, especially in pigeons, that led to the thoughts of natural selection over long periods. It is the hand of man directing many trial and error selections that is responsible.