Venus Flytrap

(Dionaea muscipula)

Domain:          Eukaryotic

Kingdom:        Plantae  

Phylum:          Anthophyta 

Class:               Magnoliopsida             

Order:             Caryophyllales             

Family:           Droseraceae  

Genus:             Dionaea          

Species:           Dionaea muscipula

Root-Maggot Flies

Domain:          Eukaryotic

Kingdom:        Animalia  

Phylum:          Arthropoda 

Class:               Insecta           

Order:             Diptera           

Family:           Anthomyiidae

Genus:             Anthomyia     

Species:           Anthomyia oculifera

Biogeography, Ecology & Habitat

It is native to the bogs and swamplands of North and South Carolina. It has been introduced to a few other states and is also popular as a potted plant in many parts of the world. It prefers lots of sunlight, humid conditions, and nutrient poor, acidic soil. Native Venus flytrap plants have a habitat that has full sun, good air circulation, and porous, well draining, acidic and moist soil that is usually poor in nutrients such as, nitrogen. 

General Adaptations

For reproductive purposes, the flowers of Venus flytraps usually grow on tall stalks far above the leaves. This is so that the insects pollinating the flowers don’t get trapped in the leaves. This is an anatomical adaptation that affects the flowers and the stems. 

Another anatomical adaptation is the hair-like teeth at the edge of the leaves that helps seal the prey inside. Sealing the prey inside prevents other predators from coming along and stealing an insect or any nutrient being washed away by water or rain before the plant can digest them. The leaves are affected because of this adaptation.

Special Adaptation

Since Venus flytraps live in nutrient poor soil, they have adapted to capture and digest insects to supplement their nutrient need.

One of the adaptations that make Venus flytrap a Venus fly trap is its trapping mechanism. The two leaf parts of a trap are laced together by a small stalk called petiole and there is a series of tiny, sensitive hairs. If an unwary insect walks across these hairs, touching two or more of them in succession, the leaf will close quickly, trapping the insect. It is then slowly digested and absorbed by the leaf. Glands on the leaf surface secrete several digestive enzymes that help to digest the insect. The leaf then re-opens for another victim after one is digested.

This is an anatomical adaptation that affects the leaves of the plant. This is because, the leaves carry out photosynthesis like any other plant, but they also have many sensitive trigger hairs that allow the leaves to close and hair-like teeth at the edge of the leaves to prevent the prey from escaping. It is also a behavioural trait because, the just functions this way. It is also a physiological and chemical adaptation because the tiny, sensitive hairs inside leaves cause the leaves to close, if triggered. There is nectar and a smell that attracts the insects, and there are also glands on the leaf surface that secrete digestive enzymes to help decompose and digest the insect. This adaptation provides the plant with the essential nutrients that it cannot get from the nutrient-poor soil.

Evolution by Natural Selection

If Charles Darwin had found this plant during his travels, he would have explained this adaptation through the idea of the survival of the fittest or natural selection. He would have said that the trait for trapping and digesting insects for nutrients existed in some individuals of the population while it did not exist or was very poor for other individuals. He might have said that Venus flytraps that have triggers which are more sensitive, faster reflexes to close the leaves faster, have teeth at the edge of the leaves and/or produce better digestive enzymes are better suited to survive the local conditions; while the individuals that do not carry these traits will not get enough nutrition to survive, so their population will slowly decline and eventually disappear since they also cannot reproduce. Individuals that are better suited to survive do not need to depend on the soil for nutrition and instead can trap and digest insects for nutrients. They can survive to produce offsprings and pass on these strong, helpful traits. This process has happened and will continue to happen slowly over time.

Lamarckian Evolution

If Jean Baptiste de Lamarck had seen this plant he would have described the evolution of this trait according to the theory of inheritance of acquired traits. He would have said, whatever traits the Venus fly trap has acquired during its lifetime, it has passed it on to its offspring. For example, if the plant grew really healthy because it has received a lot of sunlight, perfect soil condition, and sufficient nutrients, it will pass on this trait to its offspring too and they will also be healthy.

Modern Synthesis

Venus flytrap has evolved from other carnivorous plants. After a DNA analysis performed by Ken Cameron of the University of Wisconsin, it has been confirmed that Venus flytrap and waterwheel plant are related. This means Venus flytrap, a snap-trap plant, has evolved from sticky-trap plants. The sticky-trap plants must have at first started adapting by moving its tentacles and leaves to increase the chance of sticking a passing insect. Next it sped up how quickly it detected the prey and responded. Then, it must have become selective so it only traps live insects. Finally, it must have evolved its tentacles into sensory hairs and teeth that detect and wrap around the insects, and also losing its sticky glands and growing new digestive glands capable of digesting the insects. This is all so that the plant can get more nutrients by capturing bigger insects.

Coevolution

Flies are attracted to and find their food through smell. The Venus flytrap has evolved just that. It uses a sweet-smelling nectar to lure the prey into its traps. This symbiotic relationship between the Venus fly trap and root-maggot flies, or any other flies and insects it feeds on, is a parasitic relationship; the plant benefits by gaining nutrients at the the extent of its prey's life. Click here to watch a video of the Venus fly trap in action, i.e. trapping and digesting a fly.

Human Influence

The Venus flytrap is naturally found only in North and South Carolina. Even though they are being introduced in other places, they are still very rare. Since people are becoming more and more fascinated by these exotic, carnivorous plants, they are being bought and sold as potted plants. They are being sold online and in stores. It is becoming so common for people to collect and grow them that it is not hard at all to find caring instructions and tips for these plants online. These plants are definitely threatened since they are declared vulnerable. Venus flytraps help keep the pest insect population in balance by preying on them. There will definitely be a big rise in the insect population if these plants become extinct. This will throw the ecosystem off balance, and that's why these rare plant species should be left in the nature, where they can do their job.

References

http://www.bbc.co.uk/gardening/plants/plant_finder/plant_pages/9886.shtml

http://bioweb.uwlax.edu/bio203/s2007/knoblauc_kris/

http://www.botany.org/Carnivorous_Plants/venus_flytrap.php

http://www.botany.org/bsa/misc/carn.html

https://sites.google.com/site/venusflyrap/venus-flytrap/adaptations

http://news.bbc.co.uk/earth/hi/earth_news/newsid_8151000/8151644.stm

http://www.britannica.com/blogs/2009/07/the-carnivorous-venus-flytrap/