"The most comprehensive survey ever into the state of the planet concludes that human activities threaten the Earth's ability to sustain future generations. The report says the way society obtains its resources has caused irreversible changes that are degrading the natural processes that support life on Earth . . . The Millennium Ecosystem Assessment (MA) was drawn up by 1,300 researchers from 95 nations over four years.

• In some regions such as the Middle East and North Africa, humans use 120% of renewable [water] supplies (due to the reliance on groundwater that is not recharged).


• Since about 1980, approximately . . . 20% of the world's coral reefs have been destroyed and a further 20% badly degraded or destroyed.


• The use of phosphorus fertilizers and the rate of phosphorus accumulation in agricultural soils both increased nearly threefold between 1960 and 1990.


• In some sea areas, the total weight of fish available to be captured is less than a hundredth of that caught before the onset of industrial fishing.


• Some 12% of birds, 25% of mammals, and at least 32% of amphibians are threatened with extinction over the next century.

"In the class discussion after I had finished my presentation [on Easter Island] the apparently simple question that most puzzled my students was one whose actual complexity hadn't sunk into me before: How on earth could a society make such an obviously disastrous decision to cut down all the trees on which it depended? One of the students asked what I thought the islander who cut down the last palm tree said as he was doing it. ... The parallels between Easter Island and the whole modern world are chillingly obvious . . . Polynesian Easter was as isolated in the Pacific Ocean as the Earth is today in space. When the Easter Islanders got into difficulties, there was nowhere to which they could flee, nor to which they could turn for help; nor shall we modern Earthlings have recourse elsewhere if our troubles increase. Those are the reasons why people see the collapse of Easter Island society as a metaphor, a worst-case scenario, for what may lie ahead of us in our own future.