剑桥雅思4 Test 2阅读Passage 3原文翻译 玩耍的重要性 play is a serious business
Playing is a serious business. Children engrossed in a make-believe world, fox cubs play-fighting or kittens teasing a ball of string aren’t just having fun. Play may look like a carefree and exuberant way to pass the time before the hard work of adulthood comes along, but there’s much more to it than that. For a start, play can even cost animals their lives. Eighty per cent of deaths among juvenile fur seals occur because playing pups fail to spot predators approaching. It is also extremely expensive in terms of energy. Playful young animals use around two or three per cent of their energy cavorting, and in children that figure can be closer to fifteen per cent. ‘Even two or three per cent is huge,’ says John Byers of Idaho University. ‘You just don’t find animals wasting energy like that,’ he adds. There must be a reason.
玩耍是项十分重要的事情。孩子沉浸在自己幻想的世界中，狐狸幼崽嬉戏打闹，小猫拨弄线球，这些行为都不是单纯的为了娱乐。玩耍看起来像是成年努力工作时期到来之前的一种无忧无虑，精力充沛的打发时间方式。但它的意义远不止如此。首先，玩耍甚至会使动物丧命。在幼年的海狗中，有80％的死亡是因为幼崽在玩耍中未能发现掠食者接近而造成的。就能量而言，它也是极其昂贵的。玩耍的幼小动物消耗的能量大约占其总能量的2%到3%。而在儿童中，这一比例可能接近15 ％。 “即使百分之二到百分之三都是巨大的”， 爱达荷大学的约翰·拜尔斯（John Byers ）说。“你找不到动物像这样子浪费能量，“ 他补充道。一定有其他原因的。
But if play is not simply a developmental hiccup, as biologists once thought, why did it evolve? The latest idea suggests that play has evolved to build big brains. In other words, playing makes you intelligent. This article is from Laokaoya website. Playfulness, it seems, is common only among mammals, although a few of the larger-brained birds also indulge. Animals at play often use unique signs – tail-wagging in dogs, for example – to indicate that activity superficially resembling adult behaviour is not really in earnest. A popular explanation of play has been that it helps juveniles develop the skills they will need to hunt, mate and socialise as adults. Another has been that it allows young animals to get in shape for adult life by improving their respiratory endurance. Both these ideas have been questioned in recent years.
Take the exercise theory. If play evolved to build muscle or as a kind of endurance training, then you would expect to see permanent benefits. But Byers points out that the benefits of increased exercise disappear rapidly after training stops, so any improvement in endurance resulting from juvenile play would be lost by adulthood. ‘If the function of play was to get into shape,’ says Byers, ‘the optimum time for playing would depend on when it was most advantageous for the young of a particular species to do so. But it doesn’t work like that.’ Across species, play tends to peak about halfway through the suckling stage and then decline.
Then there’s the skills-training hypothesis. At first glance, playing animals do appear to be practising the complex manoeuvres they will need in adulthood. But a closer inspection reveals this interpretation as too simplistic. In one study, behavioural ecologist Tim Caro, from the University of California, looked at the predatory play of kittens and their predatory behaviour when they reached adulthood. He found that the way the cats played had no significant effect on their hunting prowess in later life.
今年早些时候，加拿大莱斯布里奇大学的塞尔吉奥·佩利斯（Sergio Pellis）报告说，一般而言，哺乳动物的大脑大小与玩耍之间存在很强的正向联系。通过比较15个哺乳动物的测量值，他和他的团队发现更大的大脑（对于给定的体型）与更多的嬉戏息息相关。相反的规律也被发现是正确的。达勒姆大学的罗伯特·巴顿（Robert Barton）认为，由于大一点的大脑比小一点的大脑对发育刺激更为敏感，因此他们需要更多的玩耍来帮助他们成长。“我的结论是它与学习有关，与发育过程中环境对大脑的重要性有关”， 他说。
Earlier this year, Sergio Pellis of Lethbridge University, Canada, reported that there is a strong positive link between brain size and playfulness among mammals in general. Comparing measurements for fifteen orders of mammal, he and his team found larger brains (for a given body size) are linked to greater playfulness. The converse was also found to be true. Robert Barton of Durham University believes that, because large brains are more sensitive to developmental stimuli than smaller brains, they require more play to help mould them for adulthood. ‘I concluded it’s to do with learning, and with the importance of environmental data to the brain during development,’ he says.
According to Byers, the timing of the playful stage in young animals provides an important clue to what’s going on. If you plot the amount of time a juvenile devotes to play each day over the course of its development, you discover a pattern typically associated with a ‘sensitive period’ – a brief development window during which the brain can actually be modified in ways that are not possible earlier or later in life. Think of the relative ease with which young children- but not infants or adults – absorb language. Other researchers have found that play in cats, rats and mice is at its most intense just as this ‘window of opportunity’ reaches its peak.
‘People have not paid enough attention to the amount of the brain activated by play,’ says Marc Bekoff from Colorado University. Bekoff studied coyote pups at play and found that the kind of behaviour involved was markedly more variable and unpredictable than that of adults. Such behaviour activates many different parts of the brain, he reasons. Bekoff likens it to a behavioural kaleidoscope, with animals at play jumping rapidly between activities. ‘They use behaviour from a lot of different contexts – predation, aggression, reproduction,’ he says. ‘Their developing brain is getting all sorts of stimulation.’
Not only is more of the brain involved in play than was suspected, but it also seems to activate higher cognitive processes. ‘There’s enormous cognitive involvement in play,’ says Bekoff. He points out that play often involves complex assessments of playmates, ideas of reciprocity and the use of specialised signals and rules. He believes that play creates a brain that has greater behavioural flexibility and improved potential for learning later in life. The idea is backed up by the work of Stephen Siviy of Gettysburg College. Siviy studied how bouts of play affected the brain’s levels of a particular chemical associated with the stimulation and growth of nerve cells. He was surprised by the extent of the activation. ‘Play just lights everything up,’ he says. By allowing link-ups between brain areas that might not normally communicate with each other, play may enhance creativity.
What might further experimentation suggest about the way children are raised in many societies today? We already know that rat pups denied the chance to play grow smaller brain components and fail to develop the ability to apply social rules when they interact with their peers. With schooling beginning earlier and becoming increasingly exam-orientated, play is likely to get even less of a look-in. Who knows what the result of that will be?