Wild silk used to produce cloth. They usually produce a tougher and rougher silk than that from domesticated "Bombyx mori" silkworms. Wild silks are usually harvested after the moths have left the cocoons, cutting the threads in the process, so that there is not one long thread, as with domesticated silkworms. Wild silks are more difficult to bleach and dye than silk from "Bombyx mori", but most have naturally attractive colours, particularly the rich golden sheen of the silk produced by the muga silkworm from Assam, often known as Assam silk. The cocoon shells of wild silk moths are toughened or stabilized
Bombyx mandarina true or mulberry silkmoths. The origin of the domesticated silkmoth is enigmatic. It has been suggested that it is the survivor of an extinct species which diverged from the ancestors of "Bombyx mandarina" millions of years ago. However, this is based on an untenable molecular clock hypothesis that assumes that wild and domestic silkmoths evolved equally fast after their lineages diverged. Rather, the effects of artificial selection have accelerated evolution in the domestic form to a point where it is hard to trace the origin of the numerous breeds of domestic silkworms even with the most modern molecular phylogeny methods.