It can be very simple. For instance, "The highest tower is built one brick at a time." If you put a new message in the same place every time—on an overhead or on the board-students will learn to look for it when they come into the room. Music serves the same pur¬pose. It sets a positive mood for the session. | 148 ACADEMIC SKILLS Practice Activity 37 Use the procedure to write a synthesis of a reading and a lecture. Take as much time as you need to complete the synthesis. Write 150-225 words. Compare your synthesis with the example answer in Chapter 7 on page 533. Reading The Out of Africa hypothesis also called the replacement hypothesis contends that modern humans originated in Africa probably from a common ancestor. From there they migrated to other regions eventually replacing the populations of Neanderthals and other groups of ear-iter humans that may have survived Geneticists who support the replacement hypothesis argue that the similarities shared by all of the modern human populations confirm the existence of a common gene pool and perhaps even one common female ancestor. They point to the fact that many modern human traits have evolved within the past 200 000 years as evidence of the replacement hypothesis. Furthermore they cite studies of DNA in cell structures called mitochondria which codes most of the inherited traits from ancestors. Most of these studies demonstrate that the diversity among human populations is very small as compared with other species. They conclude that there was only one small population from which all other populations descended. From their point of view the evidence supports the theory that modern humans migrated from a relatively small area in Africa almost 150 000 years ago moving along a route through the Middle East 100 000 years ago and slowly populating regions throughout the world by displacing the communities of less developed humanlike species that they encountered. Paleoanthropologists concede that to date the oldest fossil remains of modern Homo sapiens have been found in Africa with the next oldest discovered in the Middle East. European fossils are dated at about 50 000 years after the African fossils. Thus it would appear that the replacement hypothesis is substantiated by archaeological evidence. Lecture Now that you .
