剑桥雅思19Test4Passage1阅读原文翻译 The impact of climate change on butterflies in Britain 气候变化对蝴蝶的影响
剑桥雅思19阅读第四套题目第一篇文章的主题为气候变化对英国蝴蝶的影响。其主要内容包括蝴蝶对气候的敏感性，为了适应气候变化所做出的改变，一年内繁殖次数的变多，以及一些特定种群数量的下降。整篇文章条理清晰，也没有特别抽象的地方，读起来还算比较通畅。下面是具体每道题目的答案解析。
第1段：
According to conservationists, populations of around two thirds of butterfly species have declined in Britain over the past 40 years. If this trend continues, it might have unpredictable knock-on effects for other species in the ecosystem. Butterfly eggs develop into caterpillars and these insects, which are the second stage in a new butterfly’s lifecycle, consume vast quantities of plant material, and in turn act as prey for birds as well as bats and other small mammals. Only by arming themselves with an understanding of why butterfly numbers are down can conservationists hope to halt or reverse the decline.
据环保人士称，在过去的40年里，英国约三分之二的蝴蝶物种数量已经出现了下降趋势。如果这种趋势持续下去，可能会对生态系统中的其他物种产生不可预料的连锁反应。蝴蝶从卵孵化成毛毛虫，来到生命周期中的第二阶段。这些毛毛虫会大量啃食植物，而它们本身又是鸟类、蝙蝠以及其他小型哺乳动物的重要食物来源。环保人士只有真正了解蝴蝶数量减少的原因，才能有希望阻止甚至扭转这种下滑的趋势。
第2段：
Butterflies prefer outdoor conditions to be ‘just right’, which means neither too hot nor too cold. Under the conditions of climate change, the temperature at any given time in summer is generally getting warmer, leaving butterflies with the challenge of how to deal with this. This article is from Laokaoya website. One of the main ways in which species are ensuring conditions suit them is by changing the time of year at which they are active and reproduce. Scientists refer to the timing of such lifecycle events as ‘phenology’, so when an animal or plant starts to do something earlier in the year than it usually does, it is said to be ‘advancing its phenology’.
蝴蝶对户外环境的要求非常“苛刻”，既不能太热，也不能太冷。在气候变化的大背景下，夏季的气温普遍变得更高，这让蝴蝶面临如何适应的问题。很多物种为适应环境，会调整自己活跃和繁殖的时间。科学家将这种生命周期事件的时间安排称为“物候”。当某种动植物比往年更早开始某项活动时，我们就说它“提前了物候期”。
第3段：
These advances have been observed already in a wide range of butterflies – indeed,most species are advancing their phenology to some extent. In Britain, as the average spring temperature has increased by roughly 0.5 °C over the past 20 years, species have advanced by between three days and a week on average, to keep in line with cooler temperatures. Is this a sign that butterflies are well equipped to cope with climate change, and readily adjust to new temperatures? Or are these populations under stress, being dragged along unwillingly by unnaturally fast changes? The answer is still unknown, but a new study is seeking to answer these questions.
蝴蝶物候期的提前，已经在很多种类中被观察到——实际上，大多数物种的生命周期时间都有所提前。在英国，过去20年里春季的平均气温上升了大约0.5℃，为了匹配更凉爽的气候条件，蝴蝶的活动时间平均提前了三天到一周左右。这是不是说明蝴蝶已经具备了应对气候变化的能力，能够灵活适应新的温度？还是说，它们其实正处在压力之下，被迫跟上气候异常加速的变化节奏？这一问题仍然没有确切答案，不过，一项新的研究正在尝试寻找答案。
第4段：
First, the researchers pulled together data from millions of records that had been submitted by butterfly enthusiasts – people who spend their free time observing the activities of different species. This provided information on 130 species of butterflies in Great Britain every year for a 20-year period. They then estimated the abundance and distribution of each species across this time, along with how far north in the country they had moved. The data also, crucially, allowed researchers to estimate subtle changes in what time of the year each species was changing into an adult butterfly.
研究人员首先汇总了来自蝴蝶爱好者的数百万条观察记录——这些人在闲暇时间专注于观察不同蝴蝶物种的活动。这些数据涵盖了英国130种蝴蝶在过去20年间的变化情况。研究人员据此估算出每个物种的数量变化和分布范围，以及它们向英国北部迁移的趋势。更重要的是，这些记录还让他们能够追踪各物种在成年时间方面发生的微妙变化。
第5段：
Analysing the trends in each variable, the researchers discovered that species with more flexible lifecycles were more likely to be able to benefit from an earlier emergence driven by climate change. Some species are able to go from caterpillar to butterfly twice or more per year, so that the individual butterflies you see flying in the spring are the grandchildren or great-grandchildren of the individuals seen a year previously.
通过分析各项变量的变化趋势，研究人员发现，那些生命周期更为灵活的蝴蝶物种，更有可能从气候变化导致的提前羽化中获益。有些蝴蝶一年可以经历两次甚至更多次从毛毛虫变为成虫的过程，因此，春天飞舞的蝴蝶个体，实际上可能是前一年蝴蝶的孙辈甚至曾孙辈。
第6段：
Among these species, researchers observed that those which have been advancing their phenology the most over the 20-year study period also had the most positive trends in abundance, distribution and northwards extent. For these species, such as Britain’s tiniest butterfly, the dainty Small Blue, whose colonies are up to a hundred strong, some develop into butterflies early in spring, allowing their summer generations to complete another reproductive cycle by autumn so that more population growth occurs.
在对这些物种过去20年变化的研究中，研究人员观察到，那些物候期提前幅度最大的物种，也往往在种群数量、分布范围以及向北扩展的趋势上表现得最为积极。以英国最小的蝴蝶——小巧的“小蓝蝶”（Small Blue）为例，它们的种群规模最多可达上百只。一部分“小蓝蝶”会在初春就羽化为成虫，从而使得夏季的后代文章来自老烤鸭雅思能够在秋季前完成另一个繁殖周期，以推动种群进一步增长。
第7段：
Other species, however, are less flexible and restricted to a single reproductive cycle per year. For these species, there was no evidence of any benefit to emerging earlier. Indeed, worryingly, it was found that the species in this group that specialise in very specific habitat types, often related to the caterpillar’s preferred diet, actually tended to be most at harm from advancing phenology. The beautiful High Brown Fritillary, often described as Britain’s most endangered butterfly, is in this group. It is found only in coppiced woodland and limestone pavement habitats. It is also a single-generation butterfly that has advanced its phenology. This suggests that climate change, while undoubtedly not the sole cause, might have played a part in the downfall of this species.
然而，其他一些物种的适应性较差，一年只能繁殖一次。对于这些物种而言，提前羽化并没有带来任何明显好处。更令人担忧的是，研究发现，在这一类蝴蝶中，那些高度依赖特定栖息地的物种——往往与毛毛虫所偏好的食物有关——在物候期提前的情况下，反而受到的负面影响最为严重。比如美丽的“高褐斑蝶”（High Brown Fritillary），它常被称为英国最濒危的蝴蝶之一，就属于这一类。该物种仅出现在经过轮伐管理的林地和石灰岩地貌的栖息地中，而且一年只繁殖一代。虽然它的物候期已经出现提前现象，但这可能反而加剧了其数量的衰退。这表明，气候变化虽然不是唯一的原因，但可能确实在这一物种的衰落过程中起到了一定作用。
第8段：
All is not lost, however. Many of Britain’s single-generation species show the capacity, in continental Europe, to add a second generation in years that are sufficiently warm. Therefore, as the climate continues to warm, species like the Silver-studded Blue might be able to switch to multiple generations in the UK as well, and so begin to extract benefits from the additional warmth, potentially leading to population increases.
不过，情况并非全然无望。英国许多一年一代的蝴蝶物种在欧洲大陆展现出在气温足够温暖的年份可以增加第二代的能力。因此，随着气候持续变暖，像“银星蓝蝶”（Silver-studded Blue）这样的物种也许能在英国实现多代繁殖，从而受益于更高的气温，并有望推动种群数量的增长。
第9段：
More immediately, conservationists can arm themselves with all this knowledge to spot the warning signs of species that may be at risk. The White Admiral of southern England, a much sought-after butterfly, experienced a significant increase in numbers from the 1920s but has shown a considerable decline in the past 20 years. This may be because the caterpillar exists solely on a diet of a plant called honeysuckle. But it is also likely to be due to climate change.
从更现实的角度来看，保护主义者可以利用这些研究成果来识别那些可能面临风险的物种的预警信号。比如，英格兰南部颇受追捧的蝴蝶——白带凤蝶（White Admiral）的数量曾在20世纪20年代之后大幅增长，但在过去20年里却明显下降。这可能与其幼虫只以忍冬（一种植物）为食有关，但气候变化也很可能是一个重要原因。
