Wild man syndrome experiencing the condition. Some theorists believe that emotions are produced by culture and are not biological. Their emotional diversity across cultures and the way individuals think is based on their social environment and on past and future experience and expectations. Wild Pig syndrome is unusual by Western standards; however, it is common and normal in the Gururumba tribe. This syndrome got its name from the occurrence of domesticated pigs going through a temporary state in which the pig will run wild. With appropriate measures the pig can return to the domesticated pig life among the villagers. This is similar to
Wild animal suffering nature would be either unethical, unfeasible, or both. In his autobiography, Charles Darwin acknowledged that the existence of extensive suffering in nature was fully compatible with the workings of natural selection, yet maintained that pleasure was the main driver of fitness-increasing behavior in organisms. Evolutionary biologist Richard Dawkins challenged Darwin's claim in his book "River Out of Eden", wherein he argued that wild animal suffering must be extensive due to the interplay of the following evolutionary mechanisms: From this, Dawkins concludes that the natural world must necessarily contain enormous amounts of animal suffering as an inevitable consequence of Darwinian evolution.