Arboreal theory 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 theory claims that primates evolved from their ancestors by adapting to arboreal life. Primates are thought to have developed several of their traits and habits initially while living in trees. One key component to this argument is that primates relied on sight over smell. They were able to develop a keen sense of depth perception, perhaps because of the constant leaping that was necessary to move about the trees. Primates also developed hands
Prostitution among animals Prostitution among animals A few studies have suggested that prostitution exists among different species of non-human animals such as Adélie penguins and chimpanzees. The concept is also known as transactional sex. Penguins use stones for building their nests. Based on a 1998 study, media reports stated that a shortage of stones led female Adélie penguins to trade sex for stones. Some pair-bonded female penguins copulate with males who are not their mates and then take pebbles for their own nests. Chimpanzees who appear to be trading food for sex have also been described as engaging in prostitution. Prostitution in animals