In the long term, I am convinced, the quenching of life's exuberance will be more consequential to humanity than all of present-day global warming, ozone depletion and pollution combined. For practical reasons, if nothing else. Humanity's food supply comes from a dangerously narrow sliver of biodiversity. Throughout history, people have cultivated or gathered 7,000 plant species for food. Tens of thousands of species of the world's still surviving flora can be bred or provide genes to increase production in deserts, saline flats and other marginal habitats.
Natural pharmaceuticals offered by biodiversity are also underutilized.
Only a few hundred wild species have served to stock our antibiotics, anticancer agents, pain killers and blood thinners. The biochemistry of the vast majority millions of other species is an unfathomed reservoir of new and potentially more effective substances. The reason is to be found in the principles of evolutionary biology. Caught in an endless arms race, these species have devised myriad ways to combat microbes and cancer-causing runaway cells. We have scarcely begun to consult them for the experience stored in their genes.