Michelangelo’s David, the five-hundred-year-old marble statue, is regarded as an example of a perfect male body. However, he is found to have a flaw－having crossed eyes. The 28 was made during an exercise to produce a digital version of all Michelangelo’s sculptures and buildings by scanning them with a laser. The result shows the gaze directions of his eyes diverge. This is shown clearly in the full frontal image of David’s face, which cannot normally be seen because the sculpture is 16ft tall, stands on an elevated base, and is viewed from 29 at an angle at which the face is obscured by the left hand. 

   It is believed that Michelangelo did this 30 , because it provided good profiles of David when seen from all sides. 31 , Michelangelo sculpted with not only human anatomy and common imperfections in mind, but also with the viewing angle of the people on the ground. It wasn’t until science and photography enabled us to look at David in various angles and heights was it discovered that David’s eyes weren’t “perfect.” For non-technological viewing, David’s squinted eyes contribute to his stature and posture from all sides.

   An endangered animal or plant is a species that is considered in immediate danger of becoming extinct. Its population is very small and it needs active 41 to survive. Extinction has occurred throughout history, but increased dramatically in recent times due to the growth of the human population. The species extinction rate is now one species per day, which will lead to a dramatic decrease in the 42 of life on earth. 

   Many marine mammal scientists are now becoming concerned with the drop in numbers of dolphins. River dolphins that live in Asia and the Amazon are 43 due to dam building and habitat destruction. Another concern is the number of dolphins dying in the tuna fisheries of the eastern tropical Pacific. Historically, yellow-fin tuna has been caught by encircling the dolphins that swim above the tuna with purse seine nets. Over 100,000 dolphins per year died in the 1970s and early 1980s after being caught in tuna nets, and several species of dolphins in the eastern tropical Pacific are now considered 44 under the Marine Mammal Protection Act. Efforts of environmental organizations and consumers led to "dolphin-safe" labeling of canned tuna, and a 98% reduction in dolphin 45 since 1990. However, recent changes in US and international laws have reopened this complex issue, and the outcome is in doubt. Fortunately, the major companies have all promised to sell only tuna that is caught without encircling dolphins.

      Think of Suzie Hwang Pun as a traffic cop for genes. The 27-year-old chemical engineer uses polymers tocarry injected genes through the bloodstream. With a system of molecular tags, she can direct a gene, for instance,one that blocks cancer progression, to just the right spot—like the nuclei of cells in a tumor. It is a trick that couldsolve a problem in gene therapy research: a new gene does no good if it does not reach the right place. Whileviruses are the typical delivery vehicles in gene therapy, they are hard to manufacture and can be intercepted bythe immune system. Pun’s polymer materials avoid those problems and open the possibility of delivering drugs, aswell as genes, with exquisite precision. “This is the tip of the iceberg,” says Caltech chemical engineer MarkDavis. He was so excited by Pun’s accomplishments as a graduate student in his lab that he founded InsertTherapeutics in Pasadena, Calif., primarily to commercialize her work. Pun jumped at the chance to be a seniorscientist and employee number one. If all goes well, her technology could enter human trials within a few years.

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       The Giver is a story about a young boy called Jonas who lives in a society free of crime, suffering and sadness. There is no color, music or emotion, and individuality is prohibited. Everything is chosen; from your parents to your partner. At 12, children are assigned their jobs, which they will train for and do for the rest of their lives. Jonas is assigned to become the new Receiver of Memory, also known as the Giver. The Receiver holds all the bad and good memories of the past. In other words, no one in the community has any memory of humankind’s history.
       The storyline is complex enough to hold the attention of both young and old readers. The development of Jonas from a scared boy to someone willing to risk his future to save the community is enjoyable to follow. The story prompts us to reflect on the path of growing up. At first we are scared to accept that there are new responsibilities, but as we slowly get used to it, we want to move more and more away from childhood. What’s also impressive is Jonas’ loss of trust in his father. At the beginning, Jonas believes his parents completely. However, after the current Receiver shows Jonas the tape of his father killing and disposing of a new born child, Jonas loses his admiration of his father. This moment is what forces Jonas to leave the community. It is symbolic of the change from the innocent mind of a child into the questioning and educated mind of an adult.
        The ending is another aspect which makes this book interesting to read. There are two possible meanings behind the ending and readers have a choice in what it means: either Jonas freezes to death on the sled, or he has really found“ Elsewhere.” The ending shows us that, whatever happens, Jonas has made choices for himself rather than being told what to do.