The evidence is still growing, and growing worse, but we're still resisting it. When the scientists grew more serious and more impassioned about the situation, when they began giving numbers, offering proof, asking for action, we decided that we no longer believed in science. We distanced ourselves; we hoped we wouldn't be affected. The population at risk is not our population, at least not right now, so we needn't do anything right now. We might do something later.

We trust the government to take care of us, to act responsibly. Believing this is easier than taking drastic steps to stop what's happening, particularly since this government is very much intent on pursuing its present course, which results, as a side effect - though the government would not acknowledge this, or even comment on the fact that it is taking place - in the complete destruction of the affected population. The affected population is one-half of all the species presently living on earth.

Fanaticism is a driving force here, as it often is behind great crimes. This is a crime against nature, and this fanaticism is economic - the belief that money and profit should outweigh all other considerations, including survival of the species. If we maintain our current rates of consumption and environmental strategies, by the end of this century, one-half of the species now alive on earth may be extinct.

We're presiding over the greatest extermination of living species since the end of the dinosaurs. We're eliminating habitat, reliable climate, fresh water, clean air and nourishment. We're imposing intolerable living conditions on thousands of species. The current rate of extinctions is thought to be at least 1,000 times higher than the natural level. Right now, one-quarter of all mammals are endangered with extinction; one-third of all species, animal and vegetable, may be gone by 2050.

It may not be evident to us, as we sit in our cubicles, at our laptops, but we need these other species. We need the Northern lapwing, the Scottish crossbill, the king protea (South Africa's national flower), the albacore tuna, Boyd's forest dragon (an Australian lizard) - all of which are in dire straits. We're connected to everything. All living species perform functions valuable to the ecosystem, to the planet, and to the people who live on it. But species everywhere are being systematically deprived of the possibility of life.

Cutting fossil fuels and reducing greenhouse gases would save many species from vanishing, but we're not committing ourselves to that strategy. The Convention on Biological Diversity was ratified by 182 countries; the United States - largest producer of greenhouse gases - is the only industrial country that refused. America didn't want to be subject to any regulation over its destruction of the air, the water, the habitat and the voiceless inhabitants of the earth.

Others agree. Many developing countries wanted nothing in the treaty that might limit their freedom to exploit - and destroy - their natural resources. So the treaty is neither very powerful or effective, since almost everyone involved places short-term economic goals ahead of the long-term health of the planet. Similar issues affect the Kyoto Protocol. It seems we're all in this together, this destruction of species. This is an international effort.

Do we not think we need a healthy planet? Do we think that the animals dying around us means nothing? That this wholesale destruction won't affect us?

The use of fossil fuels, and the resulting climate change, is wreaking havoc everywhere. Erratic, destructive weather takes its toll on agriculture, construction, transportation and communication, as well as wildlife. Do we still think we don't belong to the affected population? What if the group we're destroying turns out to include our own?

What will we say to our children, and their children, when they learn about the beautiful, rich and varied life on earth that we were privileged to know?

(Roxana Robinson's most recent novel is ''A Perfect Stranger.'' This article first appeared in The Boston Globe.)