Dense vegetation buffers the wind so most Amazon plants are animal-pollinated. Most species such as orchids, are visited by insects, but a significant proportion are pollinated by bats (e.g., cocoa) or hummingbirds (e.g., heliconias). Trees pollinated by animals often have their flowers growing directly from the trunka phenomenon known as "cauliflory." This tree is a species in the genus Carpotroche (possibly C. mollis) a member of a widespread tropical family, the Flacourtiaceae. Variation in pollination strategies is an important factor contributing to plant species diversity.