2. MeasuringTime
• To study the past, historians must have a way to identify and describe when
things happened.
• They do that by measuring and labeling time in different ways.
3. Periods of History
• A group of 10 years is called a decade.
• A group of 100 years is known as a century.
• Ten centuries grouped together is called a millennium.
4. • Historians also divide the past into larger blocks of time known as eras.
• Prehistory is the time before people developed writing.
5. • Writing was invented about 5,500 years ago.
• The period known as Ancient History comes next.
• It ends c. A.D. 500 (c., or circa, means “about).
6. • Historians call the time period between about A.D. 500 and aboutA.D. 1400
the Middle Ages, or the medieval period.
7. • Modern History begins about A.D. 1400. It continues to the present day.
8. Calendars
• A calendar is a system for arranging days in order.
• The calendar we use today is the Gregorian Calendar.
• Pope Gregory XIII started counting from the birth of Jesus.
• Our calendar includes leap years and took more than three centuries to be
recognized around the world.
9. Dating Events
• In the Gregorian calendar, the years before the birth of Jesus are known as
“B.C.” (before Christ).The years after are called “A.D.” (anno domini, “in the
year of the Lord”).
• Years were written 1 B.C., A.D. 1.
10. • To avoid a religious reference in dating, many historians prefer to use the
initials B.C.E. (“before the common era”) and C.E. (“common era”).
11. Timelines
• Time lines show the order of events within a period of time.
• They also show the amount of time between events.
12. Archaeology
• The study of the past by looking at what people left behind.
• Discover artifacts (objects made by people).
• Include: tools, pottery, weapons, and jewelry.
14. Human Discoveries
• 1974: Paleontologist Donald Johnson made an exciting find in Africa.
• They discovered a partial skeleton of a human ancestor who lived more than
3.2 million years ago.
• Lucy was 3.5 feet tall and weighed 60 lbs.
• She had long arms and short legs and walked upright.
15. • Lucy belonged to the species Australopithicus afarensis.
• A species is a class of individuals with similar physical characteristics.
• We are Homo sapiens (“wise man”).
• Scientists believe that Homo sapiens probably developed about 150,000 to
195,000 years ago.
16. The Paleolithic Age
• Earliest part of the Stone Age.
• Began about 2.5 million years ago and lasted until around 8000 B.C.E.
17. • People often moved around in search of food.
• They were nomads (people who regularly move from place to place to
survive).
• Survived by hunting and gathering.
18. • Men hunted large animals.
• Women looked after the children and gathered (berries, fruit, grain, etc.).
19. • Men and women worked together in monogamous pairs (the first families).
20. The Invention ofTools
• Technology (tools and methods to perform tasks) was first used by
Paleolithic people.
• Before this time, sticks, stones, and tree branches served as tools.
• By the end of the Paleolithic Age, people were making smaller and sharper
tools.
21. Changing to Survive
• Climate affected how Paleolithic people lived.
• They sought protection in available natural shelters (caves, rock overhangs).
• They began to build tents and huts of animal skin, brush, and wood.
22. • Life became less difficult for Paleolithic people once they discovered how to
make fire.
23. • Paleolithic cave paintings have been found all around the world.
• Scholars believe that the paintings may have been created to record the
group’s history.
24. The Ice Ages
• Long periods of extreme cold that affected all of Earth.
• To survive, humans had to change many areas of their lives.
• Began eating meals with fat, building sturdier shelters, making warm
clothing using animal furs.
• Ice Age lasted about 90,000 years, ending between about 9,000 and 8,000
B.C.E.
25. NeolithicTimes
• Began about 8,000 B.C.E. and lasted until around 4,000 B.C.E.
• Shifted from hunting and gathering to systematic agriculture (growing food
on a regular basis).
• Caused the population to grow at a faster rate.
• People began to settle into communities.
26. • Neolithic farming villages developed throughout Europe, India, Egypt,
China, and Mexico.
• One of the oldest communities was Jericho (between present-day Israel and
Jordan).
• Established by around 8,000 B.C.E.
27. • During this time period, people made more technological advances.
28. Civilizations Emerge
• Humans continued to develop more complex cultures, or ways of life.
• One characteristic of the early civilizations was that they developed cities and
formed governments.
• Religions emerged in the new civilizations to help people explain their lives.
• People in society were organized into groups.
• People invented ways of writing in order to pass on information.
• Artists created paintings and sculptures for entertainment and practical purposes.
