Nectar is a sugar-rich liquid produced by plants in glands called nectaries, either within the flowers with which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists, which in turn provide antiherbivore protection. Common nectar-consuming pollinators include mosquitoes, hoverflies, wasps, bees, butterflies and moths, hummingbirds, honeyeaters and bats. Nectar plays an important role in the foraging economics and overall evolution of nectar-eating species; for example, nectar and its properties are responsible for the differential evolution of the African honey bee, A. m. scutellata and the western honey bee.
Nectar is an ecologically important item, the sugar source for honey. It is also useful in agriculture and horticulture because the adult stages of some predatory insects feed on nectar. For example, the social wasp species Apoica flavissima relies on nectar as a primary food source. In turn, these wasps then hunt agricultural pest insects as food for their young. For example, thread-waisted wasps (genus Ammophila) are known for hunting caterpillars that are destructive to crops. Caterpillars however, do eventually become butterflies and moths, which are very important pollinators.
Nectar secretion increases as the flower is visited by pollinators. After pollination, the nectar is frequently reabsorbed into the plant.
Nectar is derived from Greek nektar, the fabled drink of Greek gods. The word is derived as a compound of nek, meaning death, and tar, meaning the ability to overcome. The common use of nectar refers to the "sweet liquid in flowers", first recorded in AD 1600.
A nectary is floral tissue found in different locations in the flower. The different types of floral nectaries include sepal nectaries, petal nectaries, staminal nectaries found on the stamen, and gynoecial nectaries found on the ovary tissue. The nectaries also may vary in color, number, and symmetry. Nectaries can also be categorized as structural or non-structural. Structural nectaries refer to specific areas of tissue that exude nectar, such as the types of floral nectaries previously listed. Non-structural nectaries secrete nectar infrequently from non-differentiated tissues. The different types of floral nectaries coevolved depending on the pollinator that feeds on the plant's nectar. Nectar is secreted from epidermal cells of the nectaries by means of trichomes or modified stomata. The nectar comes from phloem with additional sugars that are secreted from the cells through vesicles packaged by the endoplasmic reticulum. Flowers that have longer nectaries sometimes have a vascular strand in the nectary to assist in transport over a longer distance..
Floral nectaries are used by plants to attract pollinators such as insects, hummingbirds, and other vertebrates. The pollinators feed on the nectar and depending on the location of the nectary the pollinator assists in fertilization and outcrossing of the plant as they brush against the reproductive organs, the stamen and pistil, of the plant and pick up or deposit pollen. Nectar from floral nectaries is sometimes used as a reward to insects, such as ants, that protect the plant from predators. Many floral families have evolved a nectar spur. These spurs are projections of various lengths formed from different tissues, such as the petals or sepals. They allow for pollinators to land on the elongated tissue and more easily reach the nectaries and obtain the nectar reward. Different characteristics of the spur, such as its length or position in the flower, may determine the type of pollinator that visits the flower.
Defense from herbivory is often one of the roles of extrafloral nectaries. Floral nectaries can also be involved in defense. In addition to the sugars found in nectar, certain proteins may also be found in nectar secreted by floral nectaries. In tobacco plants, these proteins have antimicrobial and antifungal properties and can be secreted to defend the gynoecium from certain pathogens.
Floral nectaries have evolved and diverged into the different types of nectaries due to the various pollinators that visit the flowers. In Melastomataceae, different types of floral nectaries have evolved and been lost many times. Flowers that ancestrally produced nectar and had nectaries may have lost their ability to produce nectar due to a lack of nectar consumption by pollinators, such as certain species of bees. Instead they focused on energy allocation to pollen production. Species of angiosperms that have nectaries use the nectar to attract pollinators that consume the nectar, such as birds and butterflies. In Bromeliaceae, septal nectaries (a form of gynoecial nectary) are common in species that are insect or bird pollinated. In species that are wind pollinated, nectaries are often absent because there is no pollinator to provide a reward for. In flowers that are generally pollinated by long-tongued organism such as certain flies, moths, butterflies, and birds, nectaries in the ovaries are common because they are able to reach the nectar reward when pollinating. Sepal and petal nectaries are often more common in species that are pollinated by short-tongued insects that cannot reach so far into the flower.
Extrafloral nectaries (also known as extranuptial nectaries) are nectar-secreting plant glands that develop outside of flowers and are not involved in pollination. They are highly diverse in form, location, size, and mechanism. They have been described in virtually all above-ground plant parts—including leaves (in which case they are known as foliar nectaries), petioles, stipules, cotyledons, fruits, and stems, among others. They range from single-celled trichomes to complex cup-like structures that may or may not be vascularized.
In contrast to floral nectaries, nectar produced outside the flower generally have a defensive function. The nectar attracts predatory insects which will eat both the nectar and any plant-eating insects around, thus functioning as 'bodyguards'. Foraging predatory insects show a preference for plants with extrafloral nectaries, particularly some species of ants and wasps, which have been observed to directly defend the plants. Among passion flowers, for example, extrafloral nectaries prevent herbivores by attracting ants and deterring two species of butterflies from laying eggs. In many carnivorous plants, extrafloral nectaries are also used to attract insect prey.
Darwin understood that extrafloral nectar "though small in quantity, is greedily sought by insects" but believe the "their visits do not in any way benefit the plant". Instead, he believed that extrafloral nectaries were excretory in nature (hydathodes). Their defensive functions were first recognized by the Italian botanist Federico Delpino in his important monograph Funzione mirmecofila nel regno vegetale (1886). Delpino's study was inspired by a disagreement with Charles Darwin, with whom he corresponded regularly.
Extrafloral nectaries have been reported in over 3941 species of vascular plants belonging to 745 genera and 108 families, 99.7% of which belong to flowering plants (angiosperms), comprising 1.0 to 1.8% of all known species. They are most common among eudicots, occurring in 3642 species (of 654 genera and 89 families), particularly among rosids which comprise more than half of the known occurrences. The families showing the most recorded occurrences of extrafloral nectaries are Fabaceae, with 1069 species, Passifloraceae, with 438 species, and Malvaceae, with 301 species. The genera with the most recorded occurrences are Passiflora (322 species, Passifloraceae), Inga (294 species, Fabaceae), and Acacia (204 species, Fabaceae). Other genera with extrafloral nectaries include Salix (Salicaceae), Prunus (Rosaceae) and Gossypium (Malvaceae).
Foliar nectaries have also been observed in 39 species of ferns belonging to seven genera and four families of Cyatheales and Polypodiales. They are absent, however, in bryophytes, gymnosperms, early angiosperms, magnoliids, and members of Apiales among the eudicots. Phylogenetic studies and the wide distribution of extrafloral nectaries among vascular plants point to multiple independent evolutionary origins of extrafloral nectaries in at least 457 independent lineages.
The main ingredients in nectar are sugars in varying proportions of sucrose, glucose, and fructose. In addition, nectars have diverse other phytochemicals serving to both attract pollinators and discourage predators. Carbohydrates, amino acids, and volatiles function to attract some species, whereas alkaloids and polyphenols appear to provide a protective function.
The Nicotiana attenuata, a tobacco plant native to the US state of Utah, uses several volatile aromas to attract pollinating birds and moths. The strongest such aroma is benzylacetone, but the plant also adds bitter nicotine, which is less aromatic, so may not be detected by the bird until after taking a drink. Researchers speculate the purpose of this addition is to discourage the forager after only a sip, motivating it to visit other plants, therefore maximizing the pollination efficiency gained by the plant for a minimum nectar output. Neurotoxins such as aesculin are present in some nectars such as that of the California buckeye. Nectar contains water, carbohydrates, amino acids, ions and numerous other compounds.
Agave nectar (more accurately, agave syrup) is a sweetener commercially produced from several species of agave, including Agave tequilana (blue agave) and Agave salmiana. Blue agave syrup contains 56% fructose as a sugar providing sweetening properties.Ambrosia
In the ancient Greek myths, ambrosia (, Ancient Greek: ἀμβροσία, "immortality") is sometimes the food or drink of the Greek gods, often depicted as conferring longevity or immortality upon whoever consumed it. It was brought to the gods in Olympus by doves.Ambrosia is sometimes depicted in ancient art as distributed by a nymph labeled with that name. In the myth of Lycurgus, an opponent to the wine god Dionysus, violence committed against Ambrosia turns her into a grapevine.Amrita
Amrita (Sanskrit: अमृत, IAST: amṛta), Amrit or Amata (also called Sudha, Amiy, Ami) is a word that literally means "immortality" and is often referred to in ancient Indian texts as nectar. "Amṛta" is etymologically related to the Greek ambrosia and carries the same meaning. Its first occurrence is in the Rigveda, where it is considered one of several synonyms for soma, the drink of the devas.
Amrit has varying significance in different Indian religions. The word Amrit is also a common first name for Sikhs and Hindus, while its feminine form is Amritā. The traditional masculine name is Amrith with the feminine name being Amritha.Bokermann's nectar bat
Bokermann's nectar bat (Lonchophylla bokermanni) is a bat species from South America. It is endemic to Brazil. It feeds on nectar, and is listed as an endangered species.Bumblebee
A bumblebee (or bumble bee, bumble-bee or humble-bee) is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related genera (e.g., Calyptapis) are known from fossils. They are found primarily in higher altitudes or latitudes in the Northern Hemisphere, although they are also found in South America where a few lowland tropical species have been identified. European bumblebees have also been introduced to New Zealand and Tasmania. Female bumblebees can sting repeatedly, but generally ignore humans and other animals.
Most bumblebees are social insects that form colonies with a single queen. The colonies are smaller than those of honey bees, growing to as few as 50 individuals in a nest. Cuckoo bumblebees are brood parasitic and do not make nests; their queens aggressively invade the nests of other bumblebee species, kill the resident queens and then lay their own eggs, which are cared for by the resident workers. Cuckoo bumblebees were previously classified as a separate genus, but are now usually treated as members of Bombus.
Bumblebees have round bodies covered in soft hair (long branched setae) called pile, making them appear and feel fuzzy. They have aposematic (warning) coloration, often consisting of contrasting bands of colour, and different species of bumblebee in a region often resemble each other in mutually protective Müllerian mimicry. Harmless insects such as hoverflies often derive protection from resembling bumblebees, in Batesian mimicry, and may be confused with them. Nest-making bumblebees can be distinguished from similarly large, fuzzy cuckoo bees by the form of the female hind leg. In nesting bumblebees, it is modified to form a pollen basket, a bare shiny area surrounded by a fringe of hairs used to transport pollen, whereas in cuckoo bees, the hind leg is hairy all round, and pollen grains are wedged among the hairs for transport.
Like their relatives the honeybees, bumblebees feed on nectar, using their long hairy tongues to lap up the liquid; the proboscis is folded under the head during flight. Bumblebees gather nectar to add to the stores in the nest, and pollen to feed their young. They forage using colour and spatial relationships to identify flowers to feed from. Some bumblebees steal nectar, making a hole near the base of a flower to access the nectar while avoiding pollen transfer. Bumblebees are important agricultural pollinators, so their decline in Europe, North America, and Asia is a cause for concern. The decline has been caused by habitat loss, the mechanisation of agriculture, and pesticides.Cave nectar bat
Cave nectar bat (Eonycteris spelaea), common names also include dawn bat, common dawn bat, common nectar bat and lesser dawn bat, is a species of megabat within the genus Eonycteris. The scientific name of the species is first published by Dobson in 1871.Goldman's nectar bat
Goldman's nectar bat (Lonchophylla mordax) is a bat species from South and Central America. It is found in Brazil, Colombia, Costa Rica, Ecuador and Panama.Greater nectar bat
The greater nectar bat or greater dawn bat (Eonycteris major) is a species of megabat within the genus Eonycteris. It is found in Brunei, Indonesia, Malaysia, and the Philippines. Its range is limited and includes Luzon to Maripipi in the Philippines and scattered parts of Borneo including Tuaran and Ranau in Sabah; Bau, Kuching and Bintulu in Sarawak.Honey
Honey is a sweet, viscous food substance produced by bees and some related insects. Bees produce honey from the sugary secretions of plants (floral nectar) or from secretions of other insects (such as honeydew), by regurgitation, enzymatic activity, and water evaporation. Bees store honey in wax structures called a honeycomb. The variety of honey produced by honey bees (the genus Apis) is the best-known, due to its worldwide commercial production and human consumption. Honey is collected from wild bee colonies, or from hives of domesticated bees, a practice known as beekeeping.
Honey gets its sweetness from the monosaccharides fructose and glucose, and has about the same relative sweetness as sucrose (granulated sugar). It has attractive chemical properties for baking and a distinctive flavor when used as a sweetener. Most microorganisms do not grow in honey, so sealed honey does not spoil, even after thousands of years.Honey provides 46 calories in a serving of one tablespoon (15 ml). Honey is regarded as safe when not taken in excessive amounts.Honey use and production have a long and varied history as an ancient activity. several cave paintings in Cuevas de la Araña, Spain, depict humans foraging for honey at least 8,000 years ago.Hummingbird
Hummingbirds are birds native to the Americas and constitute the biological family Trochilidae. They are among the smallest of birds, most species measuring 7.5–13 cm (3–5 in) in length. The smallest extant bird species is a hummingbird, the 5 cm (2.0 in) bee hummingbird weighing less than 2.0 g (0.07 oz).
They are known as hummingbirds because of the humming sound created by their beating wings which flap at high frequencies audible to humans. They hover in mid-air at rapid wing-flapping rates, which vary from around 12 beats per second in the largest species, to in excess of 80 in some of the smallest. Of those species that have been measured in wind tunnels, their top speed exceeds 15 m/s (54 km/h; 34 mph) and some species can dive at speeds in excess of 22 m/s (79 km/h; 49 mph).Hummingbirds have the greatest mass-specific metabolic rate of any homeothermic animal. To conserve energy when food is scarce, and nightly when not foraging, they can go into torpor, a state similar to hibernation, slowing metabolic rate to 1/15th of its normal rate.Long-tongued nectar bat
The long-tongued nectar bat (Macroglossus minimus), also known as the northern blossom bat, honey nectar bat, least blossom-bat, dagger-toothed long-nosed fruit bat, and lesser long-tongued fruit bat, is a species of megabat. M. minimus is one of the smallest species in the family Pteropodidae, with an average length of 60–85 mm. It has a reddish-brown colouring with relatively long hair compared to the other species. The hair on the abdomen is a lighter colour, and a dark brown stripe runs bilaterally down the top of the head and back.Nectarivore
In zoology, a nectarivore is an animal which derives its energy and nutrient requirements from a diet consisting mainly or exclusively of the sugar-rich nectar produced by flowering plants.
Nectar as a food source presents a number of benefits as well as challenges. It is essentially a solution of (as much as 80%) the simple sugars sucrose, glucose and fructose, which are easily ingested and digested, representing a rich and efficient source of nutrition. This solution is often diluted either by the plant that produces it or by rain falling on a flower and many nectarivores possess adaptations to effectively rid themselves of any excess water ingested this way.
However, nectar is an incomplete source of nutrition. While it does contain proteins and amino acids, these are found in low quantities, and it is severely deficient in minerals and vitamins. Very few organisms consume nectar exclusively over their whole life cycle, either supplementing it with other sources, particularly insects (thus overlapping with insectivores) or only consuming it exclusively for a set period. Many species are nectar robbers or nectar thieves, performing no pollination services to a plant while still consuming nectar.
Nectar is produced by flowering plants to attract pollinators to visit the flowers and transport pollen between them. Flowers often have specialized structures that make the nectar accessible only for animals possessing appropriate morphological structures, and there are numerous examples of coevolution between nectarivores and the flowers they pollinate. For example, hummingbirds and hawkmoths have long narrow beaks that can reach nectar at the bottom of long tubular flowers. Bats, meanwhile, visit open flowers where the nectar is not as deeply hidden.Orange nectar bat
The orange nectar bat (Lonchophylla robusta) is a species of bat in the family Phyllostomidae. It is found in Colombia, Costa Rica, Ecuador, Nicaragua, Panama, Peru, and Venezuela.
Feeding mechanismOrange nectar bats in Costa Rica were observed utilising a unique feeding mechanism that has not been seen in any other animal, this mechanism allows it to pull liquid against gravity using a pumping mechanism. The orange nectar bat's tongue contains two grooves filled with tiny muscles that force the nectar up into the bat's mouth. Two forces are at work here, capillary action and muscle force. The orange nectar bat likely developed this method independently of other species due to its unique mouth physiology.Peracchi's nectar bat
Peracchi's nectar bat (Lonchophylla peracchii) is a species of nectar-feeding bat in the family Phyllostomidae. It was first described from the Atlantic Forest in southeastern Brazil.Peristome
Peristome (from the Greek peri, meaning 'around' or 'about', and stoma, 'mouth') is an anatomical feature that surrounds an opening to an organ or structure. Some plants, fungi, and shelled gastropods have peristomes.Pollinator
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.
Insect pollinators include bees, (honey bees, solitary species, bumblebees); pollen wasps (Masarinae); ants; flies including bee flies, hoverflies and mosquitoes; lepidopterans, both butterflies and moths; and flower beetles. Vertebrates, mainly bats and birds, but also some non-bat mammals (monkeys, lemurs, possums, rodents) and some lizards pollinate certain plants. Among the pollinating birds are hummingbirds, honeyeaters and sunbirds with long beaks; they pollinate a number of deep-throated flowers. Humans may also carry out artificial pollination.
A pollinator is different from a pollenizer, a plant that is a source of pollen for the pollination process.Sunbird
The sunbirds and spiderhunters make up a family, Nectariniidae, of passerine birds. They are small, slender passerines from the Old World, usually with downward-curved bills. Many are brightly coloured, often with iridescent feathers, particularly in the males. Many species also have especially long tail feathers. Their range extends through most of Africa to the Middle East, South Asia, South-east Asia and southern China, to Indonesia, New Guinea and northern Australia. Species diversity is highest in equatorial regions.
There are 145 species in 16 genera. Most sunbirds feed largely on nectar, but will also eat insects and spiders, especially when feeding their young. Flowers that prevent access to their nectar because of their shape (for example, very long and narrow flowers) are simply punctured at the base near the nectaries, from which the birds sip the nectar. Fruit is also part of the diet of some species. Their flight is fast and direct, thanks to their short wings.
The sunbirds have counterparts in two very distantly related groups: the hummingbirds of the Americas and the honeyeaters of Australia. The resemblances are due to convergent evolution brought about by a similar nectar-feeding lifestyle. Some sunbird species can take nectar by hovering like a hummingbird, but they usually perch to feed.Tube-lipped nectar bat
The tube-lipped nectar bat (Anoura fistulata) is a bat from Ecuador. It was described in 2005. It has a remarkably long tongue, which it uses to drink nectar. It additionally consumes pollen and insects.Western nectar bat
The western nectar bat (Lonchophylla hesperia) is a species of bat in the family Phyllostomidae. It is found in Ecuador and Peru. It is threatened by habitat loss.
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