Rafflesia
Description
The Rafflesia flowers are the largest flowers in the world; the petals can reach over 90 centimetres across (Attenborough, 1995). Rafflesia is a parasite that depends completely upon its host which means that the majority of the plant’s tissues exist as thread-like strands entirely within the host’s cells (Western Michigan University, N/A). The Rafflesia plant is itself not visible until the reproduction stage when flowers first bud through the vine and then open into the magnificent sight that is world-renowned today (Nais, 2001). The flowers can take up to ten months to develop from the first visible bud to the open bloom, which may last no more than a few days. Currently 17 species of Rafflesia are recognised and these mainly differ in the form and structure of their flowers (Nais, 2001). In general, the flowers consist of five petals that are orange in colour and mottled with cream-coloured warts. There is a deep hole in the centre of the flower containing a central raised disc that supports many vertical spines. Size of flower diameter is up to 91 cm (Attenborough, 1995).
The Rafflesia flowers are the largest flowers in the world; the petals can reach over 90 centimetres across (Attenborough, 1995). Rafflesia is a parasite that depends completely upon its host which means that the majority of the plant’s tissues exist as thread-like strands entirely within the host’s cells (Western Michigan University, N/A). The Rafflesia plant is itself not visible until the reproduction stage when flowers first bud through the vine and then open into the magnificent sight that is world-renowned today (Nais, 2001). The flowers can take up to ten months to develop from the first visible bud to the open bloom, which may last no more than a few days. Currently 17 species of Rafflesia are recognised and these mainly differ in the form and structure of their flowers (Nais, 2001). In general, the flowers consist of five petals that are orange in colour and mottled with cream-coloured warts. There is a deep hole in the centre of the flower containing a central raised disc that supports many vertical spines. Size of flower diameter is up to 91 cm (Attenborough, 1995).
Biology
The enormous Rafflesia flowers are believed to be pollinated by flies; the central disk flies crawl underneath it where they come into contact with the sexual organs (Attenborough, 1995). It has been reported that the flowers have a strong smell of rotting flesh but it is unclear whether this acts to attract flies or is merely a by-product of the decaying petals, which reduce into a black slimy mess after around four days (Attenborough, 1995).
The enormous Rafflesia flowers are believed to be pollinated by flies; the central disk flies crawl underneath it where they come into contact with the sexual organs (Attenborough, 1995). It has been reported that the flowers have a strong smell of rotting flesh but it is unclear whether this acts to attract flies or is merely a by-product of the decaying petals, which reduce into a black slimy mess after around four days (Attenborough, 1995).
Habitat
Rafflesia plants are specialist parasites only found in association with specific species of the host vine Tetrastigma spp. These vines are found in both primary and secondary rainforest (Nais, 2001).
Rafflesia plants are specialist parasites only found in association with specific species of the host vine Tetrastigma spp. These vines are found in both primary and secondary rainforest (Nais, 2001).
Threats
Rafflesia are inherently rare as a result of a number of factors of their life cycle; they have a double habitat specialisation, as they can only successfully parasitise particular species and these species in turn are found only in specific habitats (Nais, 2001). In addition to this factor, there is an extremely unbalanced sex ratio in the Rafflesia flowers observed, with many more male than female flowers (Nais, 2001). Flower buds have a high level of mortality and only 10 to 18 percent go on to bloom, these only lasting for a few days; the chances of a male and female flower being in bloom at the same time in a close enough vicinity to be pollinated is therefore extremely slim (Nais, 2001). In addition to these inherent factors, there is widespread habitat destruction within much of the rainforested area of Southeast Asia and Rafflesia buds are also collected for traditional medicine and to treat fertility problems.
Rafflesia are inherently rare as a result of a number of factors of their life cycle; they have a double habitat specialisation, as they can only successfully parasitise particular species and these species in turn are found only in specific habitats (Nais, 2001). In addition to this factor, there is an extremely unbalanced sex ratio in the Rafflesia flowers observed, with many more male than female flowers (Nais, 2001). Flower buds have a high level of mortality and only 10 to 18 percent go on to bloom, these only lasting for a few days; the chances of a male and female flower being in bloom at the same time in a close enough vicinity to be pollinated is therefore extremely slim (Nais, 2001). In addition to these inherent factors, there is widespread habitat destruction within much of the rainforested area of Southeast Asia and Rafflesia buds are also collected for traditional medicine and to treat fertility problems.
Conservation
Rafflesia species are protected in a number of reserves within their range such as Kinabalu Park in Sabah on the island of Borneo. Habitat protection is one of the key factors in securing the future of this species and this magnificent flower is a huge draw to tourists, bringing much needed revenue to the area. More investigation into the life cycle of this unusual species is urgently needed (Western Michigan University, N/A).
Rafflesia species are protected in a number of reserves within their range such as Kinabalu Park in Sabah on the island of Borneo. Habitat protection is one of the key factors in securing the future of this species and this magnificent flower is a huge draw to tourists, bringing much needed revenue to the area. More investigation into the life cycle of this unusual species is urgently needed (Western Michigan University, N/A).
Relation to the Course
In terms of the metabolism unit, Rafflesia technically a member of the plant kingdom. This plant challenges traditional definitions of what a plant is because they lack chlorophyll and are therefore incapable of photosynthesis. Instead, Rafflesia takes the nutrients it needs for survival from other plants. While many parasites appear like normal plants, Rafflesia lacks any observable leaves, roots, or even stems. In addition, this flower helps me understand that not all plants breath and live in the same way.
In terms of the metabolism unit, Rafflesia technically a member of the plant kingdom. This plant challenges traditional definitions of what a plant is because they lack chlorophyll and are therefore incapable of photosynthesis. Instead, Rafflesia takes the nutrients it needs for survival from other plants. While many parasites appear like normal plants, Rafflesia lacks any observable leaves, roots, or even stems. In addition, this flower helps me understand that not all plants breath and live in the same way.
References
Attenborough, D. (1995). The Private Life of Plants. London: BBC Books.
Nais, J. (2001). Rafflesia of the world. Natural History Publications Borneo.
Western Michigan University. (N/A). Rafflesia Life History. Retrieved November 11, 2013, from Biological Science: http://unix.cc.wmich.edu/~tbarkman/rafflesia/Rafflesia.html
Nais, J. (2001). Rafflesia of the world. Natural History Publications Borneo.
Western Michigan University. (N/A). Rafflesia Life History. Retrieved November 11, 2013, from Biological Science: http://unix.cc.wmich.edu/~tbarkman/rafflesia/Rafflesia.html