Ficus ( or
Specific identification of many of the species can be difficult, but members of the genus Ficus are relatively easy to recognize. Many have and a distinctive shape or habit, and their fruits distinguish them from other plants. The fruit of Ficus is an inflorescence enclosed in an urn-like structure called a syconium, which is lined on the inside with the fig's tiny flowers that develop into multiple ovaries on the inside surface. In essence, the fig fruit is a fleshy stem with multiple tiny flowers that fruit and coalesce.
Notably, three vegetative traits together are unique to figs. All figs present a white to yellowish latex, some in copious quantities; the twig shows paired stipules —or circular scars if the stipules have fallen off; the lateral veins at the base of the leaf are steep, forming a tighter angle with the midrib than the other lateral veins, a feature referred to as "triveined".
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 taxon species, however, may have taken place more recently, between 20 and 40 million years ago.
Some better-known species that represent the diversity of the genus include, alongside the common fig, whose fingered fig leaf is well known in art and iconography: the weeping fig ( F. benjamina), a hemiepiphyte with thin, tough leaves on pendulous stalks adapted to its rain forest habitat; the rough-leaved from Australia; and 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, leading to very high levels of alpha diversity. In the tropics, Ficus commonly is the most species-rich plant genus in a particular forest. In Asia, as many as 70 or more species can co-exist. Ficus species richness declines with an increase in latitude in both hemispheres.
A description of fig tree cultivation is set out in Ibn al-'Awwam's 12th-century agricultural work titled, Book on Agriculture. (pp. 277–281 (Article XXV)
The fruit typically has a bulbous shape with a small opening (the ostiole) at the outward end that allows access to . The flowers are pollinated by Fig wasp such as Pegoscapus that crawl through the opening in search of a suitable place to lay eggs. Without this pollinator service fig trees could not reproduce by seed. In turn, the flowers provide a safe haven and nourishment for the next generation of wasps. This accounts for the frequent presence of wasp larvae in the fruit, and has led to a relationship. Technically, a fig fruit proper would be only one of the many tiny matured, seed-bearing Gynoecium found inside one fig – if you cut open a fresh fig, individual fruit will appear as fleshy "threads", each bearing a single seed inside. The genus Dorstenia, also in the fig family (Moraceae), exhibits similar tiny flowers arranged on a receptacle but in this case the receptacle is a more or less flat, open surface.
Fig plants can be Monoecy (Androdioecious) or gynodioecious (hermaphrodite and female). Nearly half of fig species are gynodioecious, and therefore have some plants with inflorescences (syconium) with long styled pistillate flowers, and other plants with staminate flowers mixed with short styled pistillate flowers. The long-styled flowers tend to prevent wasps from laying their eggs within the ovules, while the short-styled flowers are accessible for egg laying.
All the native fig trees of the American continent are hermaphrodites, as well as species like Indian banyan ( F. benghalensis), weeping fig ( F. benjamina), Indian rubber plant ( F. elastica), fiddle-leaved fig ( F. lyrata), Moreton Bay fig ( F. macrophylla), Chinese banyan ( F. microcarpa), sacred fig ( F. religiosa) and sycamore fig ( F. sycomorus). The common fig ( Ficus carica) is a gynodioecious plant, as well as lofty fig or clown fig ( Ficus aspera), Roxburgh fig ( Ficus auriculata), mistletoe fig ( Ficus deltoidea), F. pseudopalma, creeping fig ( F. pumila) and related species. The hermaphrodite common figs are called "inedible figs" or "caprifigs"; in traditional culture in the Mediterranean region they were considered food for ( Capra aegagrus). In the female fig trees, the male flower parts fail to develop; they produce the "'edible figs". 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 caprifig it grew up in. In many situations, the wasp pollinator is unable to escape and dies within the fruit. When the wasp dies, it is broken down by enzymes (Ficain) inside the fig. Fig wasps are not known to transmit any diseases harmful to humans.
When a caprifig ripens, another caprifig must be ready to be pollinated. In temperate climes, wasps hibernate in figs, and there are distinct crops. Caprifigs have three crops per year; common figs have two.
Depending on the species, each fruit can contain hundreds or even thousand of seeds. Figs can be propagated by seeds, cuttings, air-layering or grafting. However, as with any plant, figs grown from seed are not necessarily genetically identical to the parent and are only propagated this way for breeding purposes.
The intimate association between fig species and their wasp pollinators, along with the high incidence of a one-to-one plant-pollinator ratio have long led scientists to believe that figs and wasps are a clear example of coevolution. Morphological and reproductive behavior evidence, such as the correspondence between fig and wasp larvae maturation rates, have 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.
According to meta-analysis of molecular data for 119 fig species 35% (41) have multiple pollinator wasp species. The real proportion is higher because not all wasp species were detected. On the other hand, species of wasps pollinate multiple host fig species. Molecular techniques, like microsatellite markers and mitochondrial sequence analysis, allowed a discovery of multiple genetically distinct, cryptic wasp species. Not all these cryptic species are sister taxa and thus must have experienced a host fig shift at some point. These cryptic species lacked evidence of genetic introgression or backcrossing indicating limited fitness for hybrids and effective reproductive isolation and speciation.
The existence of cryptic species suggests that neither the number of symbionts nor their evolutionary relationships are necessarily fixed ecologically. While the morphological characteristics that facilitate the fig-wasp mutualisms are likely to be shared more fully in closer relatives, the absence of unique pairings would make it impossible to do a one-to-one tree comparison and difficult to determine cospeciation.
This traditional classification has been called into question by recent phylogenetic studies employing genetic methods to investigate the relationships between representative members of the various sections of each subgenus. Of Corner's original subgeneric divisions of the genus, only Sycomorus is supported as monophyletic in the majority of phylogenetic studies. Notably, there is no clear split between dioecious and monoecious lineages. One of the two sections of Pharmacosycea, a monoecious group, form a monophyletic clade basal to the rest of the genus, which includes the other section of Pharmacosycea, the rest of the monoecious species, and all of the dioecious species. These remaining species are divided into two main monophyletic lineages (though the statistical support for these lineages is not as strong as for the monophyly of the more derived clades within them). One consists of all sections of Urostigma except for section Urostigma s. s.. The other includes section Urostigma s. s., subgenus Sycomorus, and the species of subgenus Ficus, though the relationships of the sections of these groups to one another are not well resolved.
Figs have figured prominently in some human cultures. There is evidence that figs, specifically the common fig ( F. carica) and sycamore fig ( Ficus sycomorus), were among the first plant species that were deliberately bred for agriculture in the Middle East, starting more than 11,000 years ago. Nine subfossil F. carica figs dated to about 9400–9200 BCE were found in the early Neolithic village Gilgal I (in the Jordan Valley, 13 km, or 8.1 mi, north of Tell es-Sultan). These were a parthenogenesis type and thus apparently an early cultivar. This find predates the first known cultivation of cereal in the Middle East by many hundreds of years.
Video
Mutualism with the pollinating fig wasps
Systematics
Selected species
Subgenus Ficus
Subgenus Pharmacosycea
Subgenus Sycidium
Subgenus Sycomorus
Subgenus Synoecia
Subgenus [[Urostigma/" itemprop="url" title="Wiki: Banyan">Banyan
Unknown subgenus
Uses
Cultivation
Cultural and spiritual significance
Famous fig trees
Citations
General references
External links
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