Definition
The Venus Flytrap is a carnivorous plant that catches and digests animal prey—mostly insects and arachnids.
Basics
The Venus Flytrap is a famous carnivorous plant (a plant that feeds on small animals, such as insects). Carnivorous plants grow in soil that has little nitrogen. They receive nitrogen from the insects they trap.
The Venus flytrap is a small plant, with tiny little leaves. Its clam-shaped leaves have bristles on each edge, that lets out a good aroma to attract insects. Inside the leaves, there are very sensitive, almost invisible hairs that help the leaves snap shut when it is touched. Two hairs must be touched, to make response and close the leaves. This assures it that the thing that touched its hair is living, because non-living things do not move around.
The Venus Flytrap feeds on insects, such as ants, beetles, worms, flies, grasshoppers, and moths. First it traps the insect inside its leaves, and then lets out a liquid that helps digest the trapped animal. The plant takes the nitrogen from the insect's body, and consumes the insect.
It is important to understand that the Venus flytrap does not eat insects for food - it makes its own food to eat; the animals it digests (eats) just gives it the extra vitamins it needs.
Venus fly-traps were first discovered in North America on the coast of North and South Carolina, where it grows wild near the Cape Fear River. But people anywhere can grow Venus Flytraps in pots. There is a pretty sizable market for venus fly traps between collecters. The name is sometimes spelled Venus flytrap, Venus' flytrap, or Venus's-flytrap. It is named after the roman god of love, Venus.
Topics of Interest
The Venus Flytrap, Dionaea muscipula, is a carnivorous plant that catches and digests animal prey—mostly insects and arachnids. Its trapping structure is formed by the terminal portion of each of the plant's leaves and is triggered by tiny hairs on their inner surfaces. When an insect or spider crawling along the leaves comes into contact with one or more of the hairs twice in succession, the trap closes. The requirement of redundant triggering in this mechanism serves as a safeguard against a waste of energy in trapping objects with no nutritional value.
The plant's common name refers to Venus, the Roman goddess of love, whereas the genus name refers to Dione. Dionaea is a monotypic genus closely related to the waterwheel plant and sundews.
Description & Mechanism of trapping: The Venus Flytrap is a small plant whose structure can be described as a rosette of four to seven leaves, which arise from a short subterranean stem that is actually a bulb-like object. Each stem reaches a maximum size of about three to ten centimeters, depending on the time of year; longer leaves with robust traps are usually formed after flowering. Flytraps that have more than 7 leaves are colonies formed by rosettes that have divided beneath the ground.
The leaf blade is divided into two regions: a flat, heart-shaped photosynthesis-capable petiole, and a pair of terminal lobes hinged at the midrib, forming the trap which is the true leaf. The upper surface of these lobes contains red anthocyanin pigments and its edges secrete mucilage. The lobes exhibit rapid plant movements, snapping shut when stimulated by prey. The trapping mechanism is tripped when prey contacts one of the three hair-like trichomes that are found on the upper surface of each of the lobes. The trapping mechanism is so specialized that it can distinguish between living prey and non-prey stimuli such as falling raindrops; two trigger hairs must be touched in succession or one hair touched twice, whereupon the lobes of the trap will snap shut in about 0.1 seconds. The edges of the lobes are fringed by stiff hair-like protrusions or cilia, which mesh together and prevent large prey from escaping. (These protrusions, and the trigger hairs, also known as sensitive hairs, are probably homologous with the tentacles found in this plant’s close relatives, the sundews.) Scientists are currently unsure about the evolutionary history of the Venus flytrap; however scientists have made hypotheses that the flytrap evolved from Drosera (sundews).
The holes in the meshwork allow small prey to escape, presumably because the benefit that would be obtained from them would be less than the cost of digesting them. If the prey is too small and escapes, the trap will reopen within 12 hours. If the prey moves around in the trap, it tightens and digestion begins more quickly.
Speed of closing can vary depending on the amount of humidity, light, size of prey, and general growing conditions. The speed with which traps close can be used as an indicator of a plant's general health. Venus Flytraps are not as humidity-dependent as are some other carnivorous plants, such as Nepenthes, Cephalotus, most Heliamphora, and some Drosera.
If the prey is unable to escape, it will continue to stimulate the inner surface of the lobes, and this causes a further growth response that forces the edges of the lobes together, eventually sealing the trap hermetically and forming a 'stomach' in which digestion occurs. Digestion is catalysed by enzymes secreted by glands in the lobes.
Habitat: The Venus Flytrap is found in nitrogen-poor environments, such as bogs and wet savannahs. Small in stature and slow growing, the Venus flytrap tolerates fire well, and depends on periodic burning to suppress its competition. Fire suppression threatens its future in the wild. It survives in wet sandy and peaty soils. Although it has been successfully transplanted and grown in many locales around the world, it is found natively only in North and South Carolina in the United States, specifically within a 60 mile radius of Wilmington, North Carolina. One such place is North Carolina's Green Swamp. There also appears to be a naturalized population of Venus Flytraps in northern Florida as well as populations in the New Jersey Pine Barrens. The nutritional poverty of the soil is the reason that the plant relies on such elaborate traps: insect prey provide the nitrogen for protein formation that the soil cannot. The Venus Flytrap is not a tropical plant and can tolerate mild winters. In fact, Venus Flytraps that do not go through a period of winter dormancy will weaken and die after a period of time.
Cultivation: Venus Flytraps are popular as cultivated plants, but have a reputation for being difficult to grow. Successfully growing these specialized plants requires recreating a close approximation to the plant's natural habitat.
Venus flytraps are usually grown outside on a deck, window sill, or in the garden that receives two to four hours of sunlight.
Healthy Venus flytraps will produce scapes of white flowers in spring, however, many growers remove the flowering stem early (2~3 inches), as flowering consumes some of the plant's energy, and reduces the rate of trap production. If healthy plants are allowed to flower, successful pollination will result in the production of dozens of small, shiny black seeds.
Venus flytraps have a necessary winter dormancy period, triggered by nighttime temperatures below 10 °C (50 °F) and reduced day length.
Plants can be propagated by seed, although seedlings take several years to mature. More commonly, they are propagated by division in spring or summer.
When grown from seed, plants take around four to five years to reach maturity and will live for 20 to 30 years if cultivated in the right conditions.
Cultivars: Venus Flytraps are, by far, the most commonly recognized and cultivated carnivorous plant. They are sold as houseplants and are often found at florists, hardware stores and supermarkets. During the past ten years or so large quantities of cultivars have come into the market through tissue culture of select genetic mutations. It is through tissue culture that great quantities of plants are raised for commercial markets.
Conservation: The general consensus of most professional plant conservationists is that the best means to ensure survival of the Venus Flytrap is to protect a number of populations in their native and natural habitats, preferably as large areas of managed preserves. Although it may be possible to perpetuate the species indefinitely in cultivation, this is no substitute for protecting wild populations in their natural habitats. For example, cultivation by its very nature exerts strong artificial selection pressures that will change the species, possibly in unintended or unexpected ways. Such ex-situ conservation is severely limited also because plants become diseased or eaten and because there are unavoidable random events ranging from the greenhouse heat failing in winter to full scale wars. In essence, the safest place for the Venus flytrap is in nature. The natural beauty of the wild populations of flytraps has been marred by decades of field-collection by and for plant collectors and has taken a heavy toll. Many wet pine savannas, once inhabited by thousands of flytraps, are now pock-marked with holes where plants were dug for sale. Many of these plants end up on window sills as novelty items that die in a few short weeks or months.
Efforts should be made most vigorously, therefore, to preserve wild populations. Conservation of the flytrap means buying up and protecting lands on which it naturally grows, which then can be preserved, managed, and restored. This effort costs considerable money. One solution to the problem is to place a surcharge on each plant sold to generate funds to save wild populations.
Currently, there are estimated to be more than 3-6 million plants in cultivation compared to only 35,800 plants remaining in nature. Several prominent plant conservationists suggest the plant be labeled as Vulnerable. Precise data on the distribution of population sizes in 1992 from the Office of Plant Protection suggests a more dire state for the species. Every size class in red is slated for eventual extinction with the green ones persisting longer. In essence, all smaller populations may go extinct for stochastic reasons and, since small population are more numerous in nature now and contribute more to the total number of plants remaining in the species, most of this unique and remarkable carnivorous plant species may be going extinct soon. Note that the figure of 35,800 plants in 1992 is over 15 years old and undoubtedly, therefore, underestimates the current situation.
Popular culture: Flytrap-like plants are common in fictional works, usually in a much larger form capable of digesting a human. Probably the most famous is Audrey II in Little Shop of Horrors, a plant that needs to eat people to live (the off-Broadway play was based on a low-budget black comedy, The Little Shop of Horrors, in which the plant was named Audrey Jr.). Other fictional outings include the Philippine comic Darna, where the villain Flaviana turns Venus Flytraps into monsters as a defense. A one-time villain on Mighty Morphin Power Rangers was the Invenusable Flytrap, a humanoid plant creature. There was also a character named Venus Flytrap on the television sitcom WKRP in Cincinnati.
Cartoons frequently make use of monstrous plants; examples include, but certainly are not limited to Inspector Gadget, Darkwing Duck, The Simpsons and Zetsu, a villain character in the manga series, Naruto. Video games such as Super Mario Bros. use similar creatures called piranha plants as enemies and Rampage: Total Destruction has a venus fly trap-like plant named Venus. Another video game, called Venus the Flytrap, involves a robotic fly which tries to destroy other robotic insects. The Infocom text adventure game Leather Goddesses of Phobos features a giant (mobile) flytrap which attempts to eat the player's character. The Sims 2: University features an unlockable object, the Cow Plant, which will lure non-player characters with a cake lure and eat them if not fed regularly. The Gravemind in Halo 2 resembles a large venus flytrap.
Source: Wikipedia (All text is available under the terms of the GNU Free Documentation License and Creative Commons Attribution-ShareAlike License.)
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