Leaves clue to lemur peril

Lemurs are of great evolutionary and ecological interest. But for at least one species, in their Madagascan homeland and possibly as a result of climate change, drought poses a serious threat. In a research project that has been running for nearly 20 years, Patricia Wright from the Stony Brook University in the state of New York and her coworkers have been studying the behaviour of Madagascar's lemurs with a view to aid the protection of their habitat. For more than a decade, the Earthwatch Institute has supported this research with a volunteer workforce. Recently, Wright discovered that even a slight reduction in rainfall can increase the threat to the survival of the Milne-Edwards sifakas lemur. Only if there is enough rain during their lactation period, Wright found, will older females produce enough milk to keep their infants alive. In drier conditions, mature lemur mothers with worn teeth will not be able to chew the amounts of leaves required to produce sufficient milk, and the infant mortality will increase significantly. Wright comments that " it is shocking that just a slight change in climate, even in the rainforest where we assume there is plenty of water, can impact on infant survival so dramatically ". The lemurs can live up to 30 years and normally continue to reproduce in their third decade. (In this respect, lemurs are typical of primate biology, while human females with their long post-fertility lifespan are exceptional.) " With a potential five more births during the latter decade of each female lemur's life, the impact of climate change and deforestation on the population will be devastating, " Wright concludes. Thus, it appears that even the richest and seemingly most robust ecosystems are vulnerable to changes in the weather. Earthwatch Europe's chief scientist, Roger Mitchell, comments: " Tropical rainforests, though usually amongst the most stable habitats on Earth, are still highly sensitive to climate change. In these forests and elsewhere, the world's Features Leaf changes provide a clue to the climate threat facing one Madagascan lemur species, writes Michael Gross. Leaves clue to lemur peril threatened species are becoming ever more endangered. " In the light of these results, Earthwatch is planning to increase its research funding for such studies into mitigating, and adapting to, the potential effects of climate change on key species and habitats in the long term. Too much to chew: The Milne-Edwards sifakas lemur (Propithecus …