Monday, January 28, 2008

Fig

بسم الله الرحمن الرحيم

الْحَمْدُ لِلَّهِ رَبِّ الْعَالَمِينَ

"Reciting Salawath on our Prophet Muhammad (peace be upon him) is an activity that will be accepted by Allah, even if we don't have Ikhlas (piety)".

Scientific classification

Kingdom Plantae

Division Magnoliophyta

Class Magnoliopsida

Subclass Rosidae

Order Rosales

Family Moraceae

Genus Ficus

Ficus is a genus of about 800 species of woody trees, shrubs, vines, epiphytes, and hemi-epiphytes in the family Moraceae. Collectively known as figs, they are native throughout the tropics with a few species extending into the warm temperate zone. The so-called Common Fig (F. carica) is a temperate species from the Middle East and southern Europe, which has been widely cultivated from ancient times for its fruit, also confusingly referred to as figs. The fruit of most other species are also edible though they are usually of only local economic importance or eaten as bush food. However, they are extremely important food resources for wildlife. Figs are also of paramount cultural importance throughout the tropics, both as objects of worship and for their many practical uses. Among the more famous species are the Sacred Fig tree (Peepul, Bodhi, Bo, or Po, Ficus religiosa) and the Banyan Fig (Ficus benghalensis). The oldest living plant of known planting date is a Ficus regiliosa tree known as the Sri Maha Bodhi planted in the temple at Anuradhapura, Sri Lanka by King Tissa in 288 BC.


Figs occupy a wide variety of ecological niches. Take, for example, the Common Fig, a small temperate deciduous tree whose fingered fig leaf is well-known in art and iconography; or the Weeping Fig (perhaps better renamed the "Shopping Mall Fig", F. benjamina) a hemi-epiphyte with thin tough leaves on pendulous stalks adapted to its rain forest habitat; or the Creeping Fig (F. pumila), a vine whose small, hard leaves form a dense carpet of foliage over rocks or garden walls. Moreover, figs with different plant habits have undergone adaptive radiation in different biogeographic regions, often leading to very high levels of alpha diversity. In the tropics, it is quite common to find that Ficus is the most species-rich plant genus in a particular forest. In Asia as many as 70 or more species can co-exist.

Although identifying many of the species can be difficult, figs as a group are relatively easy to recognize. Often the presence of aerial roots or the general Gestalt of the plant will give them away. Their fruit are also distinct. The fig fruit is in fact an enclosed inflorescence, sometimes referred to as a syconium, an urn-like structure lined on the inside with the fig's tiny flowers. The unique fig pollination system, involving tiny, highly specific wasps, know as fig wasps that enter these closed inflorescences to both pollinate and lay their own eggs, has been a constant source of inspiration and wonder to biologists. Finally, there are three vegetative traits that together are unique to figs. All figs possess a white to yellowish sap (latex), some in copious quantities; the twig has paired stipules or a circular stipule scar if the stipules have fallen off; and the lateral veins at the base of the leaf are steep, that is they form a tighter angle with the midrib than the other lateral veins, a feature referred to as a "tri-veined".


Unfortunately, there are no unambiguous older fossils of Ficus. However, current molecular clock estimates indicate that Ficus is a relatively ancient genus being at least 60 million years old, and possibly as old as 80 million years. The main radiation of extant species, however, may have taken place more recently, between 20 and 40 million years ago.

Ecology and uses

Coppersmith Barbet feeding on White Fig (Ficus virens) fruit Figs are keystone species in many rainforest ecosystems. Their fruit are a key resource for some mammals including fruit bats and primates such as capuchin monkeys, langurs and mangabeys. They are even more important for some birds. Asian barbets, pigeons, hornbills, fig-parrots and bulbuls are examples of taxa which may almost entirely subsist on figs when these are in plenty. Many Lepidoptera caterpillars, for example of several Euploea species (Crow butterflies), the Plain Tiger (Danaus chrysippus), the Brown Awl (Badamia exclamationis), and Chrysodeixis eriosoma, Choreutidae and Copromorphidae moths feed on fig leaves. The Citrus Long-horned Beetle (Anoplophora chinensis) for example has larvae which feed on wood, including that of fig trees; it can become a pest in fig plantations. Similarly, the Sweet Potato Whitefly (Bemisia tabaci) is frequently found as a pest on figs grown as pot plants and with the trade in these gets spread to other localities. For some other common diseases of fig trees, see List of foliage plant diseases (Moraceae).

A page from the Mexican Huexotzinco Codex, painted on āmatlFig tree's wood is often rather soft and the latex precludes its use for many purposes; nonwithstanding, it was for example used to make mummy caskets in Ancient Egypt. On the other hand, certain fig species (mainly F. cotinifolia, F. glabrata and F. padifolia) are traditionally used in Mesoamerica to produce papel amate (Nahuatl: āmatl). Mutuba (F. natalensis) is used to produce barkcloth in Uganda. Pou (F. religiosa leaves' shape inspired one of the standard kbach rachana, decorative elements in Cambodian architecture. Weeping Fig (F. benjamina) and Indian Rubber Plant (F. elastica) are identified as powerful air-cleaning plants in the NASA Clean Air Study. Indian Banyan (F. bengalensis) and Indian Rubber Plant (and probably some other species too) have some use in herbalism; on the other hand the latter is known to be a benzene hyperaccumulator and urban or pot plants should be considered poisonous for that reason.


Figs have figured prominently in some human cultures. There is evidence that figs, specifically the Common Fig (F. carica) and Sycamore fig (F. sycomorus), were among the first - if not the very first - plant species that were deliberately bred for agriculture in the Middle East, starting more than 11,000 ago. Nine subfossil F. carica figs dated to about 9400-9200 BC were found in the early Neolithic village Gilgal I (in the Jordan Valley, 13 km north of Jericho). These were a parthenocarpic type and thus apparently an early cultivar. This find predates the cultivation of grain in the Middle East many hundreds of years.

Additionally, the fig tree has profoundly influenced culture through several religious traditions. It is one of the two sacred trees of Islam, and in East Asia, figs are pivotal in Buddhism, Hinduism and Jainism. Siddhārtha Gautama, the Supreme Buddha, is traditionally held to have found bodhi (enlightenment) while meditating under a Sacred Fig (F. religiosa). The same species was Ashvastha, the "world tree" of Hinduism. The Plaksa Pra-sravana was said to be a fig tree between the roots of which the Sarasvati River sprang forth; it is usually held to be a Sacred Fig but more probably seems to be a Wavy-leaved Fig (F. infectoria).

Fig pollination and fig fruit

The fig is commonly thought of as fruit, but it is properly the flower of the fig tree. It is in fact a false fruit or multiple fruit, in which the flowers and seeds grow together to form a single mass. The genus Dorstenia, also in the figs family (Moraceae), exhibits similar tiny flowers arranged on a receptacle but in this case the receptacle is a more or less flat, open surface.

A fig "fruit" is derived from a specially adapted type of inflorescence (an arrangement of multiple flowers). What is commonly called the "fruit" of a fig is actually a specialized structure- or accessory-fruit called a syconium. In this case, it is an involuted, nearly closed receptacle with many small flowers arranged on the inner surface. Thus the actual flowers of the fig are unseen unless the fig is cut open. In Chinese the fig is called "wú huā guǒ" or "fruit without flower". In Bengali, where the Common Fig is called dumur, it is referenced in a proverb: tumi jeno dumurer phool hoe gele ("You have become [invisible like] the dumur flower").

The syconium often has a bulbous shape with a small opening (the ostiole) at the outward end that allows access to pollinators. The flowers are pollinated by very small wasps that crawl through the opening in search of a suitable place to lay eggs. Without this pollinator service fig trees cannot reproduce by seed. In turn, the flowers provide a safe haven and nourishment for the next generation of wasps. Technically, a fig fruit proper would be one of the many tiny mature, seed-bearing flowers found inside one fig - if you cut open a fresh fig, the flowers will appear as fleshy "threads", each bearing a single seed inside.

Most figs come in two sexes: hermaphrodite and female. The former are called "inedible figs", caprifigs or Caprinae: in traditional Common Fig culture in the Mediterranean, they were considered food for goats (Capra aegagrus). In the female fig trees, the male flower parts fail to develop; they produce the "edible figs". Fig wasps grow in Common Fig caprifigs but not in the female syconiums because the female flower is too long for the wasp to successfully lay her eggs in them. Nonetheless, the wasp pollinates the flower with pollen from the fig it grew up in, so figs with developed seeds also contain dead fig wasps almost too tiny to see. Fig wasps are not known to transmit any diseases harmful to humans, and the high sugar content of dried figs renders them fairly sterile.

When a caprifig ripens, another caprifig must be ready to be pollinated. In temperate climes, wasps hibernate in figs, and there are distinct crops. Common Fig caprifigs have three crops per year; edible figs have two. The first (breba) produces small fruits called olynth. Some parthenocarpic cultivars of Common Figs do not require pollination at all, and will produce a crop of figs (albeit sterile) in the absence of caprifigs or fig wasps.

There is typically only one species of wasp capable of fertilizing the flowers of each species of fig, and therefore plantings of fig species outside of their native range results in effectively sterile individuals. For example, in Hawaii, some 60 species of figs have been introduced, but only four of the wasps that fertilize them have been introduced, so only four species of figs produce viable seeds there.

The intimate association between fig species and their wasp pollinators, along with the high incidence of a one-to-one plant-pollinator ratio has long led scientists to believe that figs and wasps are a clear example of co evolution. Morphological and reproductive behavior evidence, such as the correspondence between fig and wasp larvae maturation rates, has been cited as support for this hypothesis for many years. Additionally, recent genetic and molecular dating analyses have shown a very close correspondence in the character evolution and speciation phylogenies of these two clades.

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