My sixth job for All Yesterdays . There is a widespread belief that the horns were solely Estemmenosuchus bone and covered with leather. On the question of the functions of the horns to say that the horns were needed to attract sexual partners or fights between males. This version is supported by the fact that the horns were strong enough. Here, I decided to depict with a horn appendage composed of keratin that striralis over the life of the animal and gradually they became blunt end.