Food and nutrition.pdf

42 Diet and HealthVegetarian ArgumentsAlthough vegetarianism originated as a religious or ethical practice,it has also gained acceptance among many for aesthetic, nutritional, andeconomic reasons. Humanitarian vegetarians refuse meat because theybelieve that the killing of animals is unnecessary or cruel, or that such apractice can conceivably lead to a disregard for human life; the tradesthat the slaughter of animals supports, such as butchering, are considereddegrading. People who adhere to vegetarianism for health reasons believethat meat is harmful to the human body and that a purely vegetable dietis more nutritious.EvolutionSome people believe that humans were originaly vegetarian throughthe evolutionary process. It is not in the scope of this book to get into acomplex discussion of evolution, but here are a few background notescovering the subjectPrimates evolved from ancestral mammals more than 60 million yearsago, during the Palaeocene Era. The first known primates resembled smallrodents or tree shrew. Like tree shrews, they probably had huge appetitesand foraged at night for insects, seeds, buds and eggs on the forest floor.The Hominids probably emerged between 10 million and 5 millionyears ago, during the late Miocene. There appear to have been manyvarieties of early hominids, but many had three features in common:• Bipedalism• Omnivorous feeding patterns• Further brain expansion and elaboration.Monkeys have long canines and rather rectangular jaws. Human teethare smaller and more uniform in length, and the jaw is bow-shaped. Thejaws and teeth became less specialized during the evolution of formsleading to humans. Beginning with the earliest primates, there was a shiftfrom eating insects, then fruit and leaves, and on to a mixed diet.pe, any member of the primate families Hylobatidae (the lesser apes),which includes the gibbons (Hylobates), and Pongidae (the great apes),which includes the orangutan, the chimpanzees, and gorilla. They belongto the superfamily Cercopithecoidea, the Old World monkeys and apes.Apes, or anthropoids, are distinguished from other primates by theircomplex brains and hence intelligence, their large size, and their lack oftails. They are mainly vegetarian but, except for the gorilla, occasionallyeat smCill animals.Remains of skeletons from 4 million old australopiths were found.They were transitional between the Miocene apes and later hominids.