The last answer, "Renaissance artists made figures look solid and lifelike by using light and shadow; figures in medieval art look flat," is the correct answer.
There were of course other factors. While early humans did hunt them a lot due to the profits which they received from it (A lot of food, bones they could use for homes, fur they could use for clothing, etc.), there were also other factors such as less food for them which made them less mobile through different geographical regions, etc. (and therefore more susceptible to being hunted) that had played a part in their extinction.
People adapt to different clothing through their environment while other clothing preferences have diffused from their places of origin. Poncho is from South America while dashiki and parka are example of African clothing.
These clothings were diffuse slowly to other locations through the process of relocation diffusion. People living in folk culture still using their traditional clothing because environmental and traditional reasons. Environmental factors which include the weather, while traditional factors maybe because of the religion or tourism.
