Zoophily

Zoophily is a form of pollination whereby pollen is transferred by animals, usually vertebrates but may include invertebrates, particularly by hummingbirds and other birds, and bats, but also by monkeys, marsupials, lemurs, bears, rabbits, deer, rodents, lizards, and other animals. Zoophilous species, like entomophilous species, frequently evolve mechanisms to make themselves more appealing to the particular type of pollinator, e.g. brightly colored or scented flowers, nectar, and appealing shapes and patterns. These plant-animal relationships are often mutually beneficial because of the food source provided in exchange for pollination. Zoophilous species include Arctium, Acaena, and Galium aparine. Zoophily is a form of pollination whereby pollen is transferred by animals, usually vertebrates but may include invertebrates, particularly by hummingbirds and other birds, and bats, but also by monkeys, marsupials, lemurs, bears, rabbits, deer, rodents, lizards, and other animals. Zoophilous species, like entomophilous species, frequently evolve mechanisms to make themselves more appealing to the particular type of pollinator, e.g. brightly colored or scented flowers, nectar, and appealing shapes and patterns. These plant-animal relationships are often mutually beneficial because of the food source provided in exchange for pollination. Zoophilous species include Arctium, Acaena, and Galium aparine. Pollination is defined as the transfer of pollen from the anther to the stigma. There are many vectors for pollination, including abiotic (wind and water) and biotic (animal). There are benefits and costs associated with any vector. For instance, using animal pollination is beneficial because the process is more directed and often results in pollination. At the same time it is costly for the plant to produce rewards, such as nectar, to attract animal pollinators. Not producing such rewards is one benefit of using abiotic pollinators, but a cost associated with this approach is that the pollen may be distributed more randomly. In general, pollination by vertebrates occurs when the animal reaches inside the flowers for nectar. While feeding on the nectar, the animal rubs or touches the stamens and is covered in pollen. Some of this pollen will be deposited on the stigma of the next flower it visits, pollinating the flower (Missouri Botanical Garden 2006). Bat pollination is chiropterophily. Most bat species that pollinate flowers inhabit Africa, Southeast Asia, and the Pacific Islands, although bat pollination occurs over a geographically wide range. Many flowers are dependent on bats for pollination, such as the flowers which produce mangoes, bananas, and guavas (Celebrating Wildlife 2006). Bat pollination is an integral process in tropical communities with 500 tropical plant species completely, or partially, dependent on bats for pollination (Heithaus 1974). Also, it has been noted that outcrossing (introducing unrelated genetic material into a breeding line) by bats increases genetic diversity and is important in tropical communities (Heithaus 1974). Plants pollinated by bats often have white or pale nocturnal flowers that are large and bell shaped. Many of these flowers have large amounts of nectar, and emit a smell that attracts bats, such as a strong fruity or musky odor (Gibson 2001). Bats use certain chemical cues to locate food sources. They are attracted to odors that contain esters, alcohols, aldehydes, and aliphatic acids (Gibson 2001). The banana bat (Musonycteris harrisoni) is a nectarivorous species found only on the Pacific coast of Mexico. It has a very small geographic range and is distinguishable by its extremely long nose. The long snout and tongue, one tongue recorded as measuring 76mm, allows this bat to feed on the nectar of long tubular flowers. This bat species is small, with the head and body length ranging from 70 to 79mm. The wild banana flower is elongated with a purple color (Tellez 1999). Non-flying mammals (to distinguish them from bats) have been found to feed on the nectar of several species of plant. Though some of these mammals are pollinators, others do not carry or transfer enough pollen to be considered pollinators (Johnson 2001). This group of non-flying pollinators is mainly composed of marsupials, primates, and rodents (Johnson 2001). Well-documented studies of non-flying mammal pollination now involve at least 59 species of mammal distributed among 19 families and six orders (Carthewa 1997). As of 1997, there were 85 species of plants from 43 genera and 19 families which were visited by these mammals (Carthewa 1997). In many cases, a plant species is visited by a range of mammals. Two examples of multiple mammal pollination are the genus Quararibea which is visited by 12 species and Combretum which is visited by 8 (Carthewa 1997).