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86 MEDICINE IN THE SEVENTIES The successes and failures of scientific medicine came sharply into focus. New technology was available, but a more questioning attitude to drugs emerged. On 25 July 1978, a girl called Louise Brown became the world's first 'test-tube baby'. An egg from her mother's body had been successfully fertilized in a laboratory. For childless couples, the technique invoked new hope. Was it possible to manipulate human reproduction even more dramatically? Scientists developed 'cloning’ in the seventies. It means reproducing several identical living things from a single original. Gardeners have practised it for centuries by taking cuttings from one plant to produce others. Scientists managed to clone frogs, and people suggested that it might be possible to clone humans, too. Ira Levin examined the idea in his novel The Boys from Brazil. In it, cells from Hitler's body are implanted in women around the world to create a whole race of Hitlers. This was a terrible fantasy. But despite its possibility, most scientists rejected the idea that a complex organism such as the human body could ever be cloned. In 1979, Dr. Geoffrey Hounsfield won the Nobel Prize for physiology by developing the body scanner. This revolutionized X-ray techniques by scanning the body from all angles in three-dimensional sections. Drugs came under careful scrutiny. The morning sickness drug, Thalidomide, was found to produce deformed children, and the drug company was forced to pay millions of pounds in compensation. Doubts also grew about the contraceptive pill. Women over 35 who were heavy smokers were advised not to use it because of its dangerous side effects. In contrast, natural medicine became hugely popular, especially acupuncture, an ancient Chinese method of anaesthetizing patients by sticking pins into points in the nervous system.
87 SHARKS: MAGNIFICENT AND MISUNDERSTOOD Dr. F. Clark is a famous biologist and professor of zoology at the University of Maryland. In this article, she has described her research on sharks. My early experiments with shark behaviour at Cape Haze surprised a great many scientists - including, I must admit, myself. The experiments showed how easily many types of sharks learned to distinguish between right and wrong targets, which is a skill they developed as quickly as laboratory white rats. More recent studies of sharks’ brains, sensory systems, and types of behaviour contradict popular misconceptions of sharks as stupid, unpredictable eating machines, with nothing more than primitive brains and a good sense of smell. In fact, sharks are as predictable as any animal - even one's wife or husband - if one takes time to study and get to know them. Those of us who have had an opportunity to dive frequently with sharks do so, knowing that it is far safer to swim with these animals than to drive on an average city street or highway. The last few years have produced exciting new knowledge about Sharks. Barely a decade ago, there were only 250 accepted species; today, that number has climbed by a hundred. Sharks are a great deal more sophisticated than we once thought, and we now know that they have a higher sensitivity to electric fields than any animal ever studied. They have also been shown to orient to Earth's magnetic field. Sharks can match laboratory white rats in certain learning tests, and they have a surprisingly long retention span. Thus, they are hardly the primitive and senseless creatures that man has mistaken them for. For the most pan, the normal shark diet consists of fishes, mollusks, and crustaceans. Few sharks actually hunt or feed on marine mammals. No shark normally feeds on man. Most shark attacks on humans are bite-and-release or slashing types of actions that suggest warnings rather than attempts to kill. We accept the fact that a dog bites a stranger if the latter invades its territory. Are the rare shark attacks on humans caused by the similar invasion of what the shark considers its territory? When we consider the rarity of shark attacks among hundreds of millions of swimmers each year, we should ask ourselves a moral question: Because we like to swim and dive in an environment unnatural to our species, is it right for us to kill off tens of thousands of harmless inhabitants of that environment to ensure our peace of mind? We have invented many sports that are more hazardous than going into the sea. When we kill ourselves at these, we blame no one else and simply accept the risks. But when it comes to sharing the sea, we insist that sharks take all the risks. With further research we may one day be able to predict sharks' behaviour with great accuracy. When that day comes, I feel certain we will recognize that sharks present no threat to mankind.
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