The apartments are named after her, but it's 18th cent decoration.So it was on the wall of ?Mary, Queen of Scots’ apartment, meaning second half of 16th century then? (Why yes, I Googled.) Were there chickens as actual chickens at that time in China?
I don’t know when jungle fowl and chickens became recognizably different at various locations.
There was quite a bit of discussion about the relative importance of different varieties of jungle fowl in the evolution of modern chickens a long way back on this thread, but if I remember aright it was very text-based, and I don't remember any historic illustrations being brought into the frame.