Day reading Passage (Australian culture and culture shock)


Stride (n)  - a long step when walking or running. 11



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30 DAY READING CHALLENGE

Stride (n) 
- a long step when walking or running.


11 
Ankle (n) 
- the joint (= place where two bones are connected) between the foot and 
the leg, or the thin part of the leg just above the foot.
Example: I fell over and sprained/twisted my ankle.
12 
Locomotion (n) 
- the ability to move
Example: People mostly use their legs for locomotion.
13 
Insufficient 
(C1) - not enough.
Example: There was insufficient money to fund the project.
14 
Proficient (adj) 
- skilled and experienced.
Example: It takes a couple of years o f regular driving before you become proficient at
it..
15 
Compelling (adj) 
- if a reason, argument, etc. is compelling, it makes you believe it 
or accept it because it is so strong.
Example: It’s a fairly compelling argument for going.
Example: She attributes her record-breaking speed to the length o f her stride.


Day 23
You should spend about 20 minutes on Questions 14-26, which are based on Reading
Passage 2 below.
When and why did we learn to stand on our own two feet?
We may never know for exactly how long humans have walked on two legs, and the
debate about why we do it continues, but evidence and research give us plenty of clues.
В
For many years, scientists and 
anthropologists disagreed about 
w hether early humans started 
walking on two legs before or after 
their brain had increased. The 
predominant view was that brain size 
was important, and until our brains 
had reached a particular size and 
mass, bipedal movement would have 
been impossible. Then, in 1974, two 
scientists, Donald Johanson and 
Tom Gray, were mapping a remote 
area of Ethiopia when by chance 
they came across some fossilised 
bones which appeared to be from 
an early human, Australopithecus 
afarensis. Excavation of the site led 
to the discovery of several hundred 
more bones and bone fragments, 
all from a single skeleton. Scientific 
research of the bones later that year 
showed that they were 3.2 million 
years old and belonged to a young 
fem ale hominid who the scientists 
nicknamed ‘Lucy’. Most remarkably, 
however, the research showed that 
while Lucy had a very small brain 
compared with humans today, she 
was also bipedal.
How did the scientists know this? 
Lucy’s leg bones were angled 
relative to the condyles (knee joint
surfaces), which allow bipeds to 
balance on one leg at a time when 
walking. There was also a prominent 
lip in the knee to prevent the patella 
(the knee cap) from dislocating due 
to this angle. Evidence was also 
found in Lucy’s pelvis, which was 
able to accommodate an upright 
stance and the need to balance on 
only one limb with each stride. The 
shape of her ankle also showed that 
her big toes would have aligned with 
her other toes, which would have 
sacrificed manipulative abilities for 
efficiency in bipedal locomotion. Her 
feet, therefore, would have been 
used almost exclusively for getting 
around rather than for holding 
things. Finally, her backbone showed 
evidence of the spinal curvature 
necessitated by a permanent upright 
stance.
Lucy’s discovery was exciting for 
two reasons. Not only was she 
bipedal in spite of her brain size, 
but she was also believed to be 
our oldest ancestor. However, a 
discovery over thirty years later 
changed all that. In 2005, Professor 
Yohannes Haile-Selassie, head of 
Physical Anthropology at Cleveland 
Museum of Natural History, led an


Reading Passage 2
international team that discovered 
and analysed a 3.6-million-year-old 
fossilised partial male skeleton. It 
was found in the W oranso-Mille are 
of Ethiopia’s A far region, and it took 
Professor Haile-Selassie’s team 
over five years to excavate. The 
team recovered the most complete 
shoulder blades ever found in the 
human fossil record. A significant 
portion of the rib cage was also 
found.

It was a significant find because 
this early hominid, also a member 
of Australopithecus afarensis, is 
400,000 years older than Lucy, and 
significantly larger in size. Research 
on the new specimen revealed that 
advanced, human-like bipedalism 
occurred much earlier than 
previously thought. The specimen 
was nicknamed ‘Kadanuumuu’ , 
which means ‘big man’ in the Afar 
language and reflects its large size. 
The male hominid stood between 1.5 
and 1.7 metres tall, while Lucy stood 
only 1.1 metres tall. This individual 
was fully bipedal and had the ability 
to walk almost exactly like modern 
humans.

Kadanuumuu’s discovery was 
important for another reason.
Despite all the research, there were 
still some in the scientific world who 
felt there was insufficient proof that 
Lucy walked fully upright. ‘AS a 
result of our discovery,’ said 
Haile-Selassie, ‘we can now 
confidently say that Lucy and her 
relatives were almost as proficient 
walking on two legs as we are, 
and that the elongation of our 
legs came earlier in our evolution 
than previously thought. Until 
now, all of our understanding
of Australopithecus afarensis’ 
locomotion has been dependent on 
Lucy Unfortunately, because she 
was an exceptionally small female 
with very short legs, this gave some 
researchers the impression that 
she was not fully adapted to upright 
walking. This new skeleton falsifies 
that impression because if Lucy’s 
frame had been as large as this 
specimen, her legs would also have 
been proportionally longer.’

Professor Haile-Selassie’s research 
goes a long way to explain when 
humans began walking upright. 
However, one tantalising question 
remains: why did we start walking 
upright? There are several schools 
of thought, but two are particularly 
compelling. One is that bipedal 
activity is linked to the need to carry 
as much as possible. ‘Something 
as simple as carrying, an activity 
we engage in every day, might 
have, under the right conditions
led to upright walking,’ says Dr 
Brian Richmond, who carried out 
research on bipedal movement in 
apes. ‘Standing on two legs allowed 
early humans to carry more at one 
time because it freed their hands.’
It is possible to observe this in 
apes. While many are capable of 
short bursts of bipedal movement, 
they only choose to do it when 
they need to carry something. And, 
interestingly, the more valuable the 
object is to them, the more they are 
prepared to walk on just two legs in 
order to carry it.

However, another group of
researchers working at the University 
of Arizona has conducted a study 
which suggests that walking upright 
is more beneficial because it


Day 23
saves energy. ‘For decades now 
researchers have debated the role 
and evolution of bipedalism ,’ said 
David Raichlen, Assistant Professor 
of Anthropology. ‘However, the big 
problem in the study of bipedalism 
was that there was little data out 
there.’ Under his guidance, a group 
of researchers at the University 
trained five chimpanzees to walk on 
an exercise machine while wearing 
masks that allowed measurement 
of their oxygen consumption. The 
chimps were measured both while 
walking upright and while moving 
on their legs and knuckles. That
measurement of the energy needed 
to move around was analysed 
alongside results from similar tests 
on humans. Raichlen discovered 
that humans walking on two legs 
use only one-quarter of the energy 
that chimpanzees use while knuckle- 
walking on four limbs. And of course 
using less energy means you need 
to eat less, which leaves more time 
for other things.


Which paragraph contains the following information?
Write the correct letters, A-G, in boxes 14-18 on your answer sheet.

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