History is the study of past events and how they influence the present. DNA evidence suggests that all modern humans descend from a group who lived in Africa around 60,000 years ago and began migrating worldwide. Climate changes thousands of years ago, such as one around 535 AD that caused global cooling, can be studied through ice cores, tree rings, and carbon dating. Differences in the environments of continents influenced the development of civilizations through factors like available domesticated plants and animals and rates of cultural diffusion. The Columbian Exchange following Christopher Columbus' voyage in 1492 was a massive biological exchange between the Eastern and Western hemispheres that spread diseases and transformed global populations.

1. What is history?
By: Shaw Kobayashi

2. Journey of Man
● Around 45,000 years ago, a group of simple people in East
Africa began to behave in new ways and rapidly expanding in
population and range.
1. Drama evidence of a surge in ingenuity and adaptability comes from a wave
of human migration around 40,000 to 35,000 years ago.
2. Fully modern Africans made their way into Europe, where they encountered
the Neanderthals, cave dwellers who had lived in and around Europe for
more than 200,000 years.
3. Modern Africans took advantage of a long warm spell to expand northward
into Neanderthal territory in the Middle East, only to scuttle south again
when temperatures later plunged.

3. Journey of Man
● DNA studies suggest that all humans today descend
from a group of African ancestors who about 60,000
years ago began a remarkable journey.
1. The Genographic Project is seeking to chart new knowledge about the
migratory history of the human species by using sophisticated laboratory and
computer analysis of DNA contributed by hundreds of thousands of people
from around the world.
2. Analyzing historical patterns in DNA from participants around the world to
better understand our human genetic roots have three components of the
project.
3. The three are to gather field research data in collaboration with indigenous and
traditional peoples around the world; to invite the general public to join the
project by purchasing a Genographic Project public Participation Kit; and to
use proceeds from Genographic Public Participation Kit sales to further field
research and the Genographic Legacy Fund which in turn supports indigenous
conservation and revitalization projects.

4. Catastrophe
● Around the year 535 A.D, very strange activity
happened to the world's Climate.
1. Clouds of dust developed on the Earth. Rain poured red, the
sun began to go dark, bitter cold gripped the land for two
years.
2. It followed by Drought, Plague and Famine, some feared it
was the end of the world.
3. For years no one was sure what had cause this great
catastrophe.

5. Catastrophe
● Scientists are able to look back at
climatic changes that happened
thousands of years ago. There are
three ways.
● Ice cores- There are layers of ice build
from years of snow compressed into layers
of ice.
● Tree rings- Each ring has a year to it as the
tree gets older the more layers it will have.
● Carbon dating- The carbon Dioxide starts
from plants and transfers through out the
food chain and if an organism dies the
process is stoped.

6. Guns, Germs, and Steel
● The future of Human history as a Science is the striking differences
between the long term histories of people of the different continents
have been due not to innate differences in the peoples themselves but
to differences in their environments. There are four sets of differences
appear to be the most important ones.
1. The first one consists of continental differences in the wild plant and animal species available
as starting materials for domestication.
2. The second set of factors consists of those affecting rates of diffusion and migration, which
differed greatly among continents
3. The third set of factors influencing diffusion between continents, which may also help build
up a local pool of domesticates and technology.
4. The fourth set of factors consists of continental differences in area or total population size.

7. Guns, Gems, and Steel
● Christopher Columbus, an Italian
by birth, switched his allegiance to
the duke of Anjou in France then to
the king of Portugal
1. Most of the kings refused to sponsor Columbus
on his journey over seas.
2. Finally the king and queen of Spain, who denied
Columbus's first request but eventually granted
his renewed appeal.
3. It took Columbus five tries persuading one of
Europe's hundreds of princes to sponsor him on
his journey over seas to America.

8. The Columbian Exchange
● Humans have reversed the ancient trend of geographical bio
diversification
● The most influential example of this is from the exchange of
organisms between the Eastern and Western Hemispheres.
● It began with the Amerindians who brought with them a number of
different species and diseases.
● Another influential example is when the Europeans made contact
across the Atlantic Ocean and Pacific Ocean. There motives were
economic and nationalistic, not biological. Their intentions were to
gain money and expand empires, but the most important aspect of
their advance was spreading old world DNA.

9. The Columbian Exchange
● The Columbian exchange was an exchange
between the Eastern and Western
Hemispheres. It was an exchange of plants,
animals, diseases, and even slaves.
● Christopher Columbus' voyage in 1492
launched this huge exchange. It is named
after him.
● The Columbian Exchange wasn't all good.
It spread diseases in places where people
had no immunities, and depopulated many
places.
● The diseased places lost between 50 to 90
percent of their population.