At the very least, the signing of the agreement in Nagoya late last night is the moment when the international community at last began to take the destruction of the natural world seriously.

Biodiversity loss has long been the Cinderella of global politics. For many years, while governments have prioritised the reduction of world poverty, and more recently, have taken on board the real threat of climate change, the remorseless destruction of the world's habitats, ecosystems, species and natural genetic material has been an afterthought.

With great foresight, the generation of politicians who made a first attempt at saving the planet at the Earth Summit in Rio de Janeiro in 1992, not only established a UN convention on climate change; they established a UN convention on biodiversity (the CBD). But while the climate treaty has grown in importance until by last year in Copenhagen it was exercising the whole world, with more than 100 presidents and prime ministers arguing the toss over it, the CBD has never attracted the attention of world leaders.

Even now, it is environment ministers rather than premiers who have presided over the Nagoya deal – but that in itself was a huge step forward, since the meetings used to be left to officials.

What's changed? There has been a belated recognition of the scale of the crisis facing the natural world, not least because the global target to halt the pace of biodiversity loss by 2010, agreed in 2002, has conspicuously not been met. A report from the International Union For the Conservation of Nature released in Nagoya this week revealed that one in five of the world's vertebrates – the planet's mammals, birds, reptiles, amphibians and fish – is now threatened with extinction, while a report from the Royal Botanic Gardens, Kew, in September revealed a similar situation for plants. The world's politicians are at last waking up to the fact that this is not a matter of concern merely for middle-class birdwatchers, as some developmentalists used to dismiss it, but a threat to the fabric of all life, including our own. In this they have been helped by the emergence of the powerful idea of ecosystem services – the fact that a rainforest, say, is not just a wildlife reserve, but an ecosystem which provides communities with oxygen, clean water, rain, fuelwood and many other services which are essential and potentially worth billions of dollars.

Now we have the Nagoya agreement ... This is terrific, but there is all the difference in the world between signing an agreement and enforcing it, and the hope for the coming years must be that enough collective political will can be summoned up to make sure that a global deal to save biodiversity actually means something.