All these species:
• Comprise the ecosystems that ultimately sustain all life on the planet. Their interaction provides us with many services--clean air, pure water, and fertile soil--including the regulation of atmospheric and geochemical cycles.
• Offer countless windows into the workings of the natural world.
• Provide food, shelter, medicine, and other commodities for daily life, which drive the world economy.
• Shape and inhabit the natural world,delighting our senses and refreshing our spirits.

The number of species that people have put to use is relatively small. Their enormous value is almost certainly dwarfed by the potential of still-unexplored parts of the biosphere--not just poster mammals, but organisms like bacteria, algae, mollusks, and protozoans.