Early Hominids
History is the period of the past for which we have written records, but writing has only
been around for about five thousand years. The period before written records is called
pre-history, so when we are investigating the origins of the earth and humankind the only
records we have are archaeological and geological records. Scientists have discovered
creative and sophisticated ways to decode these records.
An important discovery into the origins of humankind was made in 1974 at Olduvai Gorge in
eastern Africa, just south of the equator. Over many years a river has cut a steep-sided
valley into the earth to reveal seven stratigraphic layers dating back two million years.
Here, a team of archaeologists discovered the oldest fossilized remains of a hominid with
humanlike characteristics (the term hominid refers to a primate of the hominidae family,
of which Homo Sapiens is a member). They nicknamed the remains of this early hominid
“Lucy,” because the song “Lucy in the Sky with Diamonds,” by The Beatles, was playing on
the radio at the time of the discovery. Lucy’s remains are the most complete fossils of any
upright-walking ape ever found to date. The scientific
name given to this group is Australopithecus Afarensis
(pronounced aw-STRAL-o-PITH-e-cus A-far-EN-sis),
meaning “southern ape” of the Afar (a region in the
country of Ethiopia). Afarensis is believed to have lived
between 3 and 4 million years ago.
www.creativecommons.org
The reason Lucy is such an important piece of human
history is because she provided the first early evidence
of upright walking. Lucy was bipedal, which means she
walked on two legs. She was different from chimpanzees
and other primates, which usually walk on all fours.
Since the discovery of Lucy an even earlier form of
hominid, that scientists named Australopithecus Anamensis, has also been discovered and
proves that upright walking apes lived as far back as 4.2 million years ago; even longer than
was believed when Lucy was discovered.
A more recent upright walking ape,
Australopithecus Africanus, has also been discovered, which lived between 2.8 and 2.4
million years ago. The time line of these upright apes overlap and show that Australopiths
existed from 2.4 to 4.2 million years ago and moved to different areas of Africa.
Based on fossil records Australopithecus was the first upright-walking ape, but is not
thought to have been very intelligent, based on its skull size. They are believed to have
been between 1 and 1.5 metres tall, and probably ate leaves, fruits, and the remains of
dead animals. There is no evidence that Australopithecus made their own tools, but there
is strong evidence that they used sticks and bones to help them dig, and defend
themselves.
Early Hominids – p. 1
One of the reasons scientists hypothesize Australopiths
have been found in different regions of Africa is because
during this time in Earth’s history Africa’s landscape was
changing. The shifting of the tectonic plates brought what
is now know as India pushing into Asia, like a giant plow,
creating the Himalayas; a vast mountain range 8 kilometres
high and nearly 5000 kilometres long. The result was a
barrier that changed weather patterns and cut off much of
the moisture that used to reach Africa. The lush, dense,
tropical rainforests that used to stretch across Africa
began to die off and were replaced by open woodlands and
grassy plains. Early hominids had to adapt by learning how to
move out of the trees and cross vast grassy areas in search
of food. Many scientists believe this made it necessary to
develop the ability to walk more upright (bipedal walking), to
avoid predators.
www.usgs.org
Over time two versions of Australopiths evolved. A smaller,
delicate one like Lucy, and a larger, stronger version that
scientists call Paranthropus Boisei. This species of
australopith lived between 2.3 and 1.2 million years ago and
survived by developing particularly strong jaws that allowed
them to chew up large plant fibers in a landscape where leaves
and fruits had become scarce. Paranthropus survived for
about two million years, but it is believed they were unable to
adapt quickly enough to changing conditions, and eventually
died out.
www.wikimediacommons.org
Early Hominids – p. 2
Early Hominids – Activity
/30 Marks
Write Study Notes that address the following, in your notebooks. Be sure to include
proper headings. Use complete sentences for detailed responses.
Identify “Key Understandings” by answering the following:
1) Use the reading to define the following terms (4 Marks)
a. History:
b. Prehistory:
c. Hominid:
d. Stratigraphy:
2) Answer the following in complete sentences (11 Marks)
a. Where is Olduvai Gorge? (be as specific as possible). What is the significance of this
location?
b. Seven stratigraphic horizons, or layers, have been exposed in Olduvai Gorge.
How old is the deepest layer estimated to be? Why is this important?
c. Describe the physical characteristics of Australopithecus Africanus. When did they
exist as a species? Why are they important to us?
d. What natural event is believed to have encouraged Australopithecus to move out of
the trees? Describe what Africa was like before this event.
e. Describe the differences in physical appearance between Australopithecus Africanus
and Paranthropus Boisei?
3) Complete the following on the map outline below. (15 Marks)
a. Place any requirements identified on the Mapping Essentials sheet.
b. Draw and label the Equator and the Prime Meridian. Outline all coastlines.
c. Label the oceans, the Mediterranean Sea, Red Sea, Persian Gulf, and Africa. Color
and label Lake Victoria.
d. Locate and label Olduvai Gorge.
Early Hominids – p. 3
Early Hominids – p. 4