Cambridge 19 · Academic Reading Test 4

The impact of climate change on butterflies in Britain 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. 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. 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’. 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…

Deep-sea MiningBacteria from the ocean floor can beat superbugs and cancer. But habitats are at risk from the hunger for marine minerals When Professor Mat IJpton found that a microbe from a deep-sea sponge was killing pathogenic bugs in his laboratory, he realised it could be a breakthrough in the fight against antibiotic-resistant superbugs, which are responsible for thousands of deaths a year in the UK alone. Further tests confirmed that an antibiotic from the sponge bacteria, found living more than 700 metres under the sea at the Rockall trough in the north-east Atlantic, was previously unknown to science, boosting its potential as a life-saving medicine. But Upton, and other scientists who view the deep ocean and its wealth of unique and undocumented species as a prospecting ground for new medicines, fear such potential will be lost in the rush to exploit the deep sea’s equally rich metal and mineral resources. ‘We’re looking at the bioactive potential of marine resources, to see if there are any more medicines or drugs down there before we destroy it for ever,’ says Upton, a medical microbiologist at the University of Plymouth. Ile is among many scientists urging a halt to deep-sea mining, asking for time to weigh up the pros and cons. ‘In sustainability terms, this could be a better way of exploiting the economic potential of the deep sea,’ he argues. Oceanographers using remotely operated vehicles have spotted many new species. Among them have been sea cucumbers with tails allowing them to sail along the ocean floor, and a rare ‘Dumbo’octopus, found 3,000 metres…

The Unselfish GeneA psychologist gives his view on how humans became self-centred There has long been a general assumption that human beings are essentially selfish. We’re apparently ruthless, with strong impulses to compete against each other for resources and to accumulate power and possessions. If we are kind to one another, it’s usually because we have ulterior motives. If we are good, it’s only because we have managed to control and transcend our innate selfishness and brutality. This bleak view of human nature is closely associated with the science writer Richard Dawkins, whose 1976 book The Selfish Gene became popular because it fitted so well with-and helped to justify-the competitive and individualistic ethos that was so prevalent in late 20th-century societies. Like many others, Dawkins justifies his views with reference to the field of evolutionary psychology. Evolutionary psychology theorises that present-day human traits developed in prehistoric times, during what is termed the ‘environment of evolutionary adaptedness’. Prehistory is usually seen as a period of intense competition, when life was such a brutal battle that only those with traits such as selfishness, aggression and ruthlessness survived. And because survival depended on access to resources – such as rivers, forests and animals – there was bound to be conflict between rival groups, which led to the development of traits such as racism and warfare. This seems logical. But, in fact, the assumption on which this all rests – that prehistoric life was a desperate struggle for survival – is…