Arboreal theory and feet that were capable of grasping. This was also a result of arboreal life, which required a great deal of crawling along branches, and reaching out for fruit and other food. These early primates were likely to have eaten foods found in trees, such as flowers, fruits, berries, gums, leaves, and insects. They are thought to have shifted their diets towards insects in the early Cenozoic era, when insects became more numerous. Arboreal theory This theory is proposed by Grafton Elliott-Smith (1912) who was a neuroanatomist who was chiefly concerned with the emergence of the primate brain. The arboreal
Prostitution among animals observed. A study at Yale–New Haven Hospital trains capuchin monkeys to use silver discs as money in order to study their economic behavior. The discs could be exchanged by the monkeys for various treats. During one chaotic incident, a researcher observed what appeared to be a monkey exchanging a disc for sex. The monkey that was paid for sex immediately traded the silver disc for a grape. The researcher took steps to prevent any possibility of coins being traded for sex after his suspicions were aroused. Prostitution among animals A few studies have suggested that prostitution exists among different species