TheStoryofHumanOrigins(1)教程.pdf

…from so simple a beginning endless forms most beautiful and most wonderful have been and are being, evolved. (p.460, The Origin of Species, 1859/1979) Chapter 2 The Story of Human Origins Let us use this last sentence of Charles Darwin’s Origin of Species to start our discussion about the origin of humankind. This chapter is so named because both the paleoanthropological and genetic literature in which human origins are traced contain as many different interpretations as, if not more than, facts. The journey of human origin is many a story which also depends on the story teller. The human origin story presented here will be organized into three parts. I first present fossil records to document the existing evidence about our human odyssey. This is part 1. I will then present the two major interpretations of these data, namely, the multiregional hypothesis, which is contained in part 2, and the replacement or the Out of Africa theory in part 3. Part 1: Fossils and Dates, and Their Finders and Daters The fact that we and all the organisms on earth started from a single cell billions of years ago makes it difficult to find a starting point to narrate the history of human evolution. Since we often say (correctly) that man comes from ape, let us start with ape which arose from Old World monkeys 33 to 24 million years ago. The fossil monkey, Aegyptopithecus , which had apelike features was first found in Egypt. Other fossils found in eastern Africa and dated to be 23 to 15 million years ago were considered ancestral to man and African apes. However there were few fossil records for African apes from 6 to 13.5 million years ago. About 12 to 15 million years ago, the living apes broke into two groups that are referred to as African ape and Asian ape. The African ape group includes gorilla, chimpanzees, and man. The Asian ape group in