Any scientific discipline needs a theoretical framework to guide its development and to sharpen the questions its researchers pursue. In biology, evolution is the grand theoretical framework, and an his torical perspective is necessary to understand present-day biological conditions. In its formative years, the modern study of the fruit-frugivore mutualism was guided by the 'specialist-generalist' paradigm developed by D. Snow, D. McKey, and H. Howe. Howe reviews the current status of this evolution ary paradigm and points out that it has been dismissed by many workers before being adequately...

Although cacti such as the saguaro and organ pipe have come to define the Sonoran Desert for many people, they represent some 170 species of columnar cacti found in many parts of the Americas. These giant plants are so dominant in some ecosystems that many species of animals rely on them for food and shelter. They are pollinated by bats in central Mexico and Venezuela, by birds and bees in northern Mexico and Peru.

This book summarizes our current knowledge about the ecology, evolution, and conservation of columnar cacti and their vertebrate mutualists to show that the very...

In the darkness of the star-studded desert, bats and moths feed on the nectar of night-blooming cactus flowers. By day, birds and bees do the same, taking to blooms for their sweet sustenance. In return these special creatures pol-linate the equally intriguing plants in an ecological circle of sustainability.

The Sonoran Desert is the most biologically diverse desert in the world. Four species of columnar cacti, including the iconic saguaro and organ pipe, are among its most conspicuous plants. No Species Is an Island describes Theodore H. Fleming's eleven-year study of the...