The baobab tree is the iconic tree of the African Sahara. It is readily recognized by its enormous trunk and, by comparison, scrawny stems and twigs. It is the source of many legends among the tribes of the area, and is also a rich source of traditional medicine. In a land where rainfall is limited and it is rare to find even tiny bushes, the gigantic baobab tree thrives. It is able to do so due to a number of unique adaptations that it has perfected over the course of its evolution. Slick and Shiny
Besides it height and girth, the baobab is also distinct due to its shiny and slick outer bark. This unique adaptation allows the baobab tree to reflect light and heat, keeping it cool in the intense savanna sun. The slippery skin is also useful in keeping monkeys, elephants and other small herbivores from climbing it and eating its tender leaves and flowers. It is also believed that the reflective nature of the bark may aid in protecting the tree from the effects of wildfires. Spongy Nature
Another adaptation that the baobab tree has developed to help it conserve water is a spongy bark. The bark of the baobab is more porous than regular wood, making it able to absorb moisture like a sponge. This allows the tree to absorb as much water as possible in times of rain and store it for use during times of scarcity or drought. Stinky Flowers
The baobab tree blooms pretty white flowers. However, get too close and you are in for a surprise -- the flowers of the baobab emit a stinky smell, a smell that resembles rotting meat. This unique adaptation helps the baobab to reproduce effectively by attracting its main pollinator, the fruit bat. Other creatures that find the smell of the baobab attractive are flies, moths and ants. All of these creatures help to spread the pollen. Rainwater Collection The baobab tree has adapted its stems to catch every bit of water it can, from morning dew to summer downpours. Its stems form "u" like funnels, allowing water to channel into holding canals so the plant has time to soak it all in over the course of a day. Insects, birds and humans find this adaptation useful as well, especially when water is scarce. Bibliography:
1. Purdue University Extension; The legendary Baobab; William R. Chaney; March 2005
The Angraecum orchids, or Comet Orchids, are very interesting plants. Most come from Africa or Madagascar, though a few species come from other places. The most famous species is the Christmas Orchid, Angraecum sesquipedale. These plants are monopodial, so there's a single stem which grows upward with alternating leaves, and flower stems and roots emerge from just above the leaves. Occasionally the stem will branch. (Some species do this more than others.) Vegetatively, the plants vary widely; some are very small, others are very large; some grow upright, others hang downward. It's very hard to generalize, other than to say that they are all monopodial. They are pollinated by moths: the white color of most species makes them more visible at night (most moths are nocturnal), and the flowers are also fragrant at night. (Both of these adaptations to moth pollinators are also common in Brassavola orchids, a conspicuous example of convergent evolution that Charles Darwin didn't know about during his famous investigation of Angcm. sesquipedale.) Some species have one flower per inflorescence, while others produce several.
- The African Peyote cactus has thick stems, which helps the plant hold back water for a long time. -The cacti's leaves turn to spines which helps the plant from losing water from evaporation. - Wihout these two caracteristics, the cacti would not survive in the desert. - Mescaline, a chemical found in this plant has been found to be effective for the treatment of some diseases. So this plant can be used for medicinal reasons also. The oldest cacti date back 20.000 years ago. Its special looks are because of its ability to...
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