WHY ARE HUMANS SUCH GOOD LONG DISTANCE RUNNERS?
WHAT CAUSED OUR EVOLUTION WHAT DID WE EVOLVE INTO? BORN TO RUN
THE GREAT RIFT VALLEY OF AFRICA IS WHERE THE GREAT HUMAN EXPERIMENT TOOK PLACE
THE RIFT IS 150KMS WIDE AND 6400 KMS LONG AND WAS CREATED DUE TO THE MOVEMENT
OF TECTONIC PLATES
Various species of bipedal hominids evolved
during this time when the rainforests were
As the forest cover disappeared our ancestors evolved to disappearing in eastern Africa.
walk longer distances to nd food and exploit other food Upto 16 species of various small brained bipedal Some adaptations for walking and running in Homo erectus (compared to an Australopithecus afarensis). The
resources other than fruit such as tubers. Before even our hominins have been discovered during the time features indicated on the left would have beneted both walking and running, but the features indicated on the
brain started expanding Our ancestors evolved from period of 4-2 million years .Bipedality was highly right are primarily for running. Homo erectus could now hunt prey by chasing it down and killing it with stone
moving on 4 legs to moving on 2 legs as this was more selected tools. Homo erectus became the rst true hunter gatherer.H. erectus’s body was not 100 percent like yours,
ef cient to travel longer distances but the evolution of this key species marks the origin of a largely humanlike body, as well as the modern ways
we eat, cooperate, communicate, use tools, and otherwise behave. In essence, H. erectus was the ftrst
ancestor we can characterize as signicantly human.
THE RIFTING PROCESS CREATED MOUNTAINS ON BOTH SIDES
THAT WERE 1-2 KMS HIGH AND DEEP VALLEYS.THIS REDUCED
RAINFALL IN THE VALLEYS AND MADE THE LAND ARID.
3.6 million years ago in
Laetoli, Tanzania, three early
humans walked through wet
volcanic ash. When the
A male chimp that weighs 45 kilograms spends about 140 calories to move
nearby volcano erupted
3 kms while a human would require just around 45 calories to walk the same
again, subsequent layers of
distance. Imagine that a typical Australopithecus mother weighed 30
ash covered and preserved
kilograms and had to travel 6 kilometers a day, twice as far as a
the oldest known footprints
chimpanzee mother. If she walked as ef ciently as a human female, she
of early humans.
would save about 140 calories a day (which adds up to nearly 1,000
calories a week).When food was scarce, such differences could have a
large selective bene ts
Austrolopithecines were extremely good at walking long distances and nding food .
They had extremely strong and powerful jaw muscles and large molars to eattough
foods such as stems ,tubers,nuts etc and there is also evidence that they used to
scavenge meat from carcasses.
But australopithecines had not yet evolved features to run long distances. These
adaptations for running evolved much later down in our our evolutionary line,1.8
DUE TO RIFTING THE LAND WHICH WAS ONCE RAINFORESTS TURN INTO WOODLANDS AND million years ago in HOMO ERECTUS.
SAVANNAHS .(TREE COVER REDUCES)HOMINIDS THAT SURVIVE ON FRUIT NOW NEED TO TRAVEL
LONGER DISTANCES TO GET THEM AND THIS IS THE START OF OUR EVOLUTION.
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