------Program code: NS-080811-01920 (what's this?)
Source: CCTV.com
08-11-2008 09:32
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It's a battle between strength and quantity. The tiny ants, by working together, can defeat their giant enemy.
It’s in a microcosm such as this that it is possible to learn about the survival of the fittest, and the lasting vitality of the rainforests.
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The forest below Jiangfengling enjoys more rainfall than any other in China. The lingering high temperatures and the plentiful rainfall combine to ensure that the forest flourishes.
But too much rain can cause trouble. Most of the plants in the rainforest have evolved so that their leaves are long and narrow. Their shape allows them to drain the water away and prevent rotting. It’s the ability of the leaves to drain water that has given rise to the name rainforest.
The Changbai Mountains have more precipitation than anywhere else in northeast China. In winter, the snow is a meter thick in the Korean pine forest. However, the snow can’t be absorbed directly by the trees, which means that if anything, the forest suffers from drought.
The broad-leaf trees have already withered. But the Korean pines are still green. Like other plants in regions of drought, the Korean pine has a remarkable ability to retain water. The surface of its leaves is waterproof and hard; the breathing holes are hidden deep in the flutes on the underside. This unique structure minimizes transpiration to the utmost.
Their unique survival skills allow the Korean pines to grow well in cold regions and become a key member of the plant community.
Numerous plants have a magical ability to adapt to water. A special example is the mangrove.
From the Zhoushan archipelago in the East China Sea to the Beibu Gulf on the South China Sea, in all the transitional areas between land and sea, mangroves are found. These forests are the lowest in the world – at precisely sea level. They can withstand typhoons and protect farmland; they also provide a nursery for many marine creatures. Through a long evolutionary process, the mangrove has developed a special ability to survive on beaches.
The Sonneratia is a type of mangrove. The bamboo-like shoots on the ground are the mangroves’ pneumatophores, with an area more than ten times that of the crown.
The quagmire lacks air, so the mangrove’s root system grows in the air to breathe. Such is the wisdom of the mangrove’s evolution. As it breathes, the system grasps the soft silt with its tentacles, giving the mangrove and the earth the ability to withstand the ocean waves and typhoons.
The sea ebbs and flows every day. After a flood tide, the short mangrove is inundated and becomes an oasis in the sea.
If a normal terrestrial plant is inundated in water with just one tenth the salt contained in seawater, it will die. So the coast where the mangrove lives is unsuitable for terrestrial plants.
However, the sap concentration in a mangrove’s root system is greater than seawater, so that the salt is filtered out and only freshwater gets through. The natural selection and evolution of billions of years has turned every mangrove into an excellent desalinator.
The tide goes down, and another inhabitant of the quagmire becomes active.
The male fiddler crabs are busy smartening themselves, and then they wave their pincers in a show of strength.
The female fiddler crab is very particular about her bridal chamber. She will inspect more than 100 caves, and then choose her mate according to the living conditions on offer.
The new house offered by this male crab apparently fails to come up to standard.
The fiddler crabs feed on sediment they find in the mud. The area is covered with toxic gas, which is generated by the putrescence created by long-term submergence in seawater. But the fiddler crabs have adapted to the habitat created by the mangroves.
A longing for home is written into the genetic code of many animals. Every spring, black storks will fly over mountains and rivers all the way from south of the Yangtze River to the Tarim River in the Taklimakan Desert, where they will breed. To the ancestors of today’s black storks, this was a fertile area of marshland. Time may change the world, but not genetic codes.
