The problems are especially urgent in developing countries, where the vast majority of biological diversity is found. Tropical forests are being cleared in response to rapid population growth and industrial development, leading to escalating pressures on fragile ecosystems.

Additional pressure comes from the global economy. The United States, with 4.5 percent of the world's population, benefits from 25 percent of the world economy. In contrast, developing countries have 80 percent of the world's population and benefit from less than 15 percent of the world's economy, with many people living in extreme poverty on less than $1 a day.

Clearly, conservation efforts can succeed in the tropics only if they balance protection of the planet with human health and prosperity.