5. The Journey of Man Spencer Wells has concluded that all humans alive today are descended from a single man who lived in Africa around 60,000 years ago. Well's take on the origins of modern humans and how they came to populate. The Journey of Man: A Genetic Odyssey, and a National Geographic documentary of the same title. In a straightforward story, he explains how he traced the exodus of modern humans from Africa by analyzing genetic changes in DNA from the y-chromosome. human ancestors originated in Africa, and eventually made their way out to the rest of the world. Analysis of the Y chromosome is one of the methods used in tracing the history of early humans early. Thirteen genetic markers on the Y-chromosome differentiate populations of human beings.
6. Catastrophe 15 hundred yrs. Ago something extreme happened to the climate. The sun became dark, rain poured red as is tinted by blood, clouds of dust enveloped the earth, cold ripped the land for 2 yrs., then came drought, famine, plague, death. Whole cites were wiped out, civilization crumbled there is evidence of a catastrophe it effected the world and history. The mid sixth century catastrophe was the most important date in the history of the past 2000 yrs. It did lay the foundation of the world we live in today.
11. Columbia Exchange The Columbian Exchange was a dramatically widespread exchange of the animals, plants, culture and human populations (including slaves), communicable, and ideas between the Eastern and Western hemispheres (Old World and New World). It was one of the most significant events concerning ecology, agriculture and culture in all of human history. Christopher Columbus' first voyage to the Americas in 1492 launched the era of large-scale contact between the old and the New Worlds that resulted in this ecological revolution, hence the name "Columbian" Exchange.
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