By Dennis Schatz - Vice President of Strategic Development
The question in this edition is:
What separates early
humans from our ape ancestors?
The Answer - bipedal
Scroll down to see the solution to our
puzzle.
Most people think it is the brain size of early humans that
separate us from the chimpanzee -- our closest primate
ancestor. But the brain size of early humans, like "Lucy"
featured in our west coast premier of →Lucy's Legacy: The Hidden Treasures of
Ethiopia,
was the same size as a modern-day chimpanzee.
The key difference is that all humans are bipedal --
walking upright on two legs. You can identify humans from
apes because of the S-shaped spine (vs. C-shaped for the
apes). The S-shape is ideal for keeping the body upright,
while a C-shape is good for animals that walk on legs and
arms. In addition, the spine of humans enters the skull in
the middle of the bottom so that the head is balanced over
the upright spine. The spine of primates enters the skull
near the back.
The pelvic bone in humans is also more rounded and farther
back compared to apes. This provides better connections to
muscles in order to walk on two feet. It gives better
balance and support to the upper body. The hand and foot of
humans also changed over time. The foot became more
designed for walking rather than grasping. The hand got
better at gripping small items, which made it better at
making tools.
Lucy is one of the most complete skeletons of early humans
ever found. Found in Ethiopia in 1974, she is an
example Australopithecus
afarensis (Southern Ape of Africa), a type of human
that lived in Africa three million years ago. The area of
Ethiopia where she was found is now a dry climate, but
three million years ago that part of Africa was a lush
forest with plenty of water and food. Although
Australopithecus
afarensis is
clearly human, it probably did not have language. It may
have used naturally occurring tools like chimpanzees do
today, but it did not make tools like later humans. If you
saw one today it would probably look like today's apes,
except that it would be bipedal.
Humans with larger brain size did not exist until around
two million years ago. The name of these larger brained
humans all start with Homo, such as Homo erectus, Homo neanderthalensis
and Homo sapiens. All of these humans made tools, but
only sapiens had the ability to do elaborate planning, use
a complex language, and produce art.
Here is the solution:
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