Traditional thinking up to now has been that the distinctive, upright body form of modern humans has come about as a result of the ability to walk, and that running is simply a by-product of walking.
Traditional thinking up to now has been that the distinctive, upright body form of modern humans has come about as a result of the ability to walk, and that running is simply a by-product of walking. Furthermore, humans have usually been regarded as poor runners compared to such animals as dogs, horses or antelopes. However, this is only true if we consider fast running, or sprinting, over short distances. Even an Olympic athlete can hardly run as fast as a horse can gallop, and can only keep up a top speed for fifteen seconds or so. Horses, antelopes and greyhounds, on the other hand, can run at top speed for several minutes, clearly outperforming us in this respect. But when it comes to long-distance running, humans do astonishingly well. They can maintain a steady pace for miles, and their overall speed compares favourably with that of horses or dogs.
Bramble and Lieberman examined twenty-six anatomical features found in humans. One of the most interesting of these is the nuchal ligament, a band of tissue that extends from a ridge on the base of the skull to the spine. When we run, it is this ligament that prevents our head from pitching back and forth or from side to side. Therefore, we are able to run with steady heads, held high. The nuchal ligament is not found in any other surviving primates, although the fossil record shows that Homo erectus, an early human species that walked upright, much as we do, also had one. Then there are our Achilles tendons at the backs of our legs, which connect our calf muscles to our heel bones-and which have nothing to do with walking. When we run, these tendons behave like springs, helping to propel us forward. Furthermore, we have low, wide shoulders, virtually disconnected from our skulls, another anatomical adaptation which allows us to run more efficiently. Add to this our light forearms, which swing out of phase with the movement of our legs to assist balance, and one begins to appreciate the point that Bramble and Lieberman are trying to make.
But what evolutionary advantage is gained from being good long-distance runners? One hypothesis is that this ability may have permitted early humans to obtain food more effectively. 'What these features and fossil facts appear to be telling us is that running evolved in order for our direct ancestors to compete with other carnivores for access to the protein needed to grow the big brains that we enjoy today,' says Lieberman.
6.
The human ability to run ______.
(A) was only recently described in a scientific journal
(B) played an important part in human evolution
(C) is now regarded as more important than the ability to climb trees
(D) is surprising when we consider evolutionary trends
7.
According to the passage, humans ______.
(A) are better runners than most other animals
(B) are not good at running short distances
(C) compare unfavorably with horses and dogs
(D) cannot run at top speed over long distances
8.
It appears that the nuchal ligament _______.
(A) is found only in modern primates
(B) enables us to run with steady heads
(C) prevents the head from moving
(D) is a unique anatomical feature among all species
9.
The passage suggests that _______.
(A) we do not need calf muscles in order to walk
(B) without shoulders we could not run very fast
(C) the movement of our forearms is out of phase
(D) our Achilles tendons are an adaptation for running
10.
According to the passage, early humans _______.
(A) killed animals by exhausting them
(B) may have evolved big brains for running
(C) competed with other animals for food
(D) could probably run before they could walk
Questions 11-15
People value money desperately because they value one another desperately; thus the cause of panic in the stock-market plunge is not that people will lose their dollars but that they will lose their sense of community. For the past couple of weeks, the nation has watched itself roll toward ruin because people were losing their money in bales. If one were tasteless enough to ask a big loser what exactly he was losing, he would sputter, "What am I losing? My car! My beautiful home! My children's educations! My clothes! My dinner! My dollars!" They are all true. People have been mourning the passing of their money for all the things that money can do, and what money can do is impressive. Money can build cities, cure diseases, and win wars. The sudden acquisition of the stuff can toss our spirits into the air like a hat.
Money can do considerably more. It offers power, an almost unique form of power, not simply because it allows us to acquire and possess things but because it is we who determine its worth; we who say a ruby costs more than an apple; we who decide that a tennis court is more valuable than a book. Paradoxically, money creates a deep sense of powerlessness as well, since technically we cannot provide money for ourselves; someone or something else must do that for us-our employers or, until recently, our stocks. All that, money can do: and when such essential, familiar functions are snatched from one's life, small wonder that people may grow wild, frantic, and even murderous.
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