The tropics at tipping point

Global biodiversity is at tipping point and on the verge of collapse, according to a major research collaboration. The team caution that urgent, concerted action is needed to reverse species loss in the tropics and prevent an environmental catastrophe. In a new study the international team, including researchers from Oxford University, Lancaster University - who led the work and the Universities of Hong Kong, Manchester Metropolitan and partners in Brazil, reveal that without quick, decisive action, the risk of species loss in the most diverse parts of the planet will be unprecedented and irrevocable - with severe knock-on effects for wildlife and people alike. The paper is the first in-depth review of all four of the world's most diverse ecosystems - savannas, tropical forests, lakes and rivers and coral reefs. The findings reveal that despite covering only 40% of the earth's surface, they are home to more than three quarters of the world's species - including almost all shallow water corals and more than 90% of bird species. Dr Erika Berenguer, a researcher at the Oxford School of Geography and Environment, Environmental Change Institute, said: 'We know that species diversity is much higher in the tropics than in temperate zones, but this paper puts into context how diverse the tropics are and exactly how much of the Earth's species depend on them for home and sanctuary. For example, from the 151,466 flowering plant species, 75% of them occur in the tropics.' Across tropical ecosystems many species face the 'double jeopardy' of being at risk from both local and human pressures, such as over fishing, selective logging and extreme weather such as droughts and heatwaves, heightened by climate change.