Evolutionary ecology of pollination and reproduction of tropical plants

Abstract

Angiosperms are the most diverse group of living plants. It is in the tropics where the striking diversity of reproductive organs (flowers) and the unparalleled variety of pollination and reproductive systems evolved. The diversification of many groups of animal pollinators such as bees, butterflies, moths, flies, wasps, hummingbirds, and bats occurs also in tropical forest. Indeed the pollination of flowering plants by animals is one of the best examples of co-evolution by natural selection. Besides, among the reproductive systems of tropical angiosperms there is a high incidence of both outcrossing species and dioecious trees. This fact stresses the reproductive dependence of tropical plants on pollinators. Consequently, the reduction and fragmentation of tropical forests is one of the major threats to the extinction of natural pollinators and the plant populations that depend upon them. Besides the negative consequences on pollinators and plant reproduction, the reduction of populations and their reproductive isolation is predicted to negatively affect the genetic diversity and structure of populations in tropical trees species. The viability and maintenance of tropical forest depends largely on the capacity of tropical trees to reproduce and regenerate under natural conditions. Hence, studies designed to understand the reproduction of tropical plants are critical. On this knowledge depends the possibility to protect biological resources and the subsequent management of tropical forests.