New alarm bells

Some species do appear to practise construction skills — birds in particular — and to require some mental flexibility in starting the process. But ultimately, animals build the way they do because they are genetically programmed to do so, Hansell concludes. But evolution can lead to surprising results. Hansell notes that most of our closest primate relatives create little more than temporary shelters of leaves and branches. Yet, he notes, the mountain gorilla feeds on a species of thistle with spiny defences. Hansell describes the very many ways the adult gorillas are able to wrap up the thistles, disarming the spines and creating edible food parcels. Young gorillas must learn these techniques. Hansell notes that creating a paper aeroplane probably takes considerably less complex processing. " If gorillas made paper aeroplanes rather than food bundles, then every museum would have one and every schoolchild would know about them. " In his survey of animal building Hansell admits to " rather liking anthropomorphism " but not as an explanation but " as a source of ideas or ... hypotheses for stimulating lines of investigation. " He enjoys the 'Isn't nature wonderful?' of much popular programming but believes this is a serious question and we need to do some more serious wondering. An alarming recent study finds that, amongst the very many environmental pressures humans are creating for other species, it is our closest relatives that appear to be coming off worst. The World Conservation Union (IUCN) is now warning that the first extinction of a primate species in more than a century is imminent, according to their latest evaluation of the threat posed to the continued existence of monkeys and apes around the world. One species of monkey that has not been seen for many years is already thought to have died out. A detailed assessment of the 394 species of primate found that 29 per cent are in danger of disappearing due to habitat loss, hunting and climate change. Some are already on the brink of extinction, the report said. One species, Miss Waldron's red colobus, found in the Ivory Coast and Ghana, is now feared to have become extinct while the golden-headed langur, in Vietnam, and China's Hainan gibbon are numbered in their dozens. The Horton Plains slender loris in Sri Lanka, has been seen just four times over the past 20 years and the Sumatran orang-utan is suffering …