Name: _____________________
Binder Number: ______
The Science of Human Origins
Introduction
History is the study of people and events through the course of
time. It tells us what they did and what happened to them.
Historians are people who study and write about the human
past. But what about the time before people developed writing?
This is an important question to ask since most of human history
has occurred without the invention of handwriting. How do
current-day historians know and understand the lives of people
who lived before people first began to write?
Define: Prehistory

Humans first appeared
on Earth around
150,000 years ago
How do we find out about human origins?
What we know about the earliest humans comes from the
things they left behind and from the hard work of scientists
who have worked to uncover these clues. By discovering and
interpreting these items, scientists can piece together a large
amount of information such as the animals they hunted, the
weapons they used, and the homes they ate at. Let’s find out
more about the 3 main types of scientists who work in the field
of human origins:
Archaeologists

Excavate sites in search of
artifacts that help determine the
way people once lived.

Anthropologists

Humans first
invented writing
around 5,200
years ago
Paleontologists
Study the____________________ 
of a people.
Study __________________ and
___________________ life.
Excavate
Culture-

Culture includes items such as:
o Food
o
o
o
o

Study __________________.

Fossils- the naturally preserved
Artifact-
Artifact examples:
o Tools
o
o
remains of animals or plants.
How
we know
old something
is? ancient fossils and artifacts is called radiocarbon dating.
One do
method
thathow
scientists
use to date
Here’s how it works: All living things on Earth are made up of carbon. Most carbon on Earth is not
radioactive, but a very small percentage is. As a result, as living things take in carbon, they also take
in a small amount of radioactive carbon.
When these life forms die, they stop taking in carbon. The carbon in their bodies at the time of their
death will remain in their bodies until they decompose or become fossilized. The radioactive carbon
in their body, however, will begin to decay and disappear at a very consistent rate. This allows
scientists to compare the normal carbon to the decaying radioactive carbon that is disappearing,
giving us the precise age of the item. Radiocarbon dating can accurately tells us the age of items
such as bone, cloth, wood, and plant fibers.
Simply put, Radiocarbon dating….
Layering
Another technique scientists use to find out how old an
artifact may be is called layering. Have you ever thought
"how do artifacts become buried so far underground?"
The answer is not that the artifacts sink, but that the
ground builds up in layers over time. In the picture to the
right, the soil resembles a layer cake, with the oldest
layers on the bottom and more recent deposits on top.
The accumulation of soil is a natural process that results
from items dying like grass and leaves, and the deposit of
blowing dust. Household waste such as ashes from
kitchen fires, food remains, and broken glass and
ceramics also contribute to the accumulation of layers.
Why is this important? Soil layers are the most basic tools
available for measuring the passing of time because the
deepest layers of soil are older than the layers on top. For
this reason, archaeologists excavate one layer at a time,
removing all soil from one time period before excavating
the layers that preceded it.
Old
Older
Oldest
Simply put, layering is…