A
pollinator is the biotic agent (
vector) that moves
pollen from the male
anthers of a
flower to the female
stigma of a flower to accomplish
fertilization or
syngamy of the female
gamete in the
ovule of the flower by the male gamete from the pollen grain. Though the terms are sometimes confused, a pollinator is different from a
pollenizer, which is a plant that is a source of pollen for the
pollination process.
The most recognized pollinators are the various species of bees, which are plainly adapted to pollination. Bees typically are fuzzy and carry an electrostatic charge. Both features help pollen grains adhere to their bodies, but they also have specialized pollen-carrying structures; in most bees, this takes the form of a structure known as the scopa, which is on the hind legs of most bees, and/or the lower abdomen (e.g., of megachilid bees), made up of thick, plumose setae. Honey bees, bumblebees, and their relatives do not have a scopa, but the hind leg is modified into a structure called the corbicula (also known as the "pollen basket"). Most bees gather nectar, a concentrated energy source, and pollen, which is high protein food, to nurture their young, and inadvertently transfer some among the flowers as they are working. Eusocial bees such as honey bees need an abundant and steady source of pollen to multiply.
Many other insects accomplish pollination. Wasps (esp. Sphecidae and Vespidae), bombyliid flies and syrphid flies are important pollinators of some plants. Beetles, midges, and even thrips or ants can sometimes pollinate flowers. Green bottle or carrion flies are important for some flowers, usually ones that exude a fetid odor. Some male Bactrocera fruit flies are exclusive pollinators of some wild Bulbophyllum orchids that have a specific chemical attractant present in their floral fragrance[1][2]. Some Diptera (flies) may be the main pollinators in higher elevations of mountains whereas Bombus species are the only pollinators among Apoidea in alpine regions at timberline and beyond. Other insect orders are rarely pollinators, and then typically only accidentally (e.g., Hemiptera such as Anthocoridae, Miridae)
Bats are important pollinators of some tropical flowers. Birds, particularly hummingbirds, honeyeaters and sunbirds also accomplish much pollination, especially of deep-throated flowers. Other vertebrates, such as monkeys, lemurs, possums, rodents and lizards[3] have been recorded pollinating some plants.
