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Orchids 'Secret
Orchids (兰花) are some of the most rare and delicate species in all of nature. For hundreds of years orchids have been prized discoveries of collectors and adventurers hoping to find new and diverse kinds of the flower. "Orchid hunters" went looking for the mysterious orchids and brought back new types to sell. However, many of them met with tragedy instead. Dozens of hunters were killed by accidents or diseases or murder. Others became food for horrible creatures.
While the plants have long been valued for their beauty, they may be even more important to science and our understanding of co-evolution. Unlike plants that can self-pollinate (自我授粉), orchids need very specific insects or birds to spread their pollen. The process by which insects, the wind, or birds spread the pollen of different flowers is called pollination. Pollen is a powder produced by plants that contains their genetic material. In order for the plants to reproduce, the pollen must be physically moved to the flower's stigma (花的柱头), which contains an egg. Now the fertilized egg can become a seed. Birds and insects can pollinate plants by touching many different flowers and spreading the pollen around.
Orchids evolved to attract insects and birds. Because there are many different species of orchid, there are also many different ways the orchids attract their pollinators. Orlean explains that" many species look so much like their favorite insects that an insect mistakes them for its relatives. and when it lands on the flower to visit, pollen sticks to its body. Another orchid imitates the shape of something that a pollinating insect likes to kill…Other species look like the mate of their pollinator, so the bug tries to mate with one orchid and then another. . . and spreads pollen from flower to flower each hopeless time. "
Other orchids don't use their shape at all, but rather produce specialized smells to attract specific insects, such as bees, beetles or flies. Some orchids smell like cake, some like chocolate, and some like rotting meat. All these smells may seem weird, but they exist to attract creatures to their pollen and help the orchids survive.
Orchids provide new angles for the research into plant and animal evolution on the earth. The strategies to attract insects and spread their flowers' pollen go on and on. Each family of orchids has a unique kind of insect or bird that visits their flowers, as well as its own way of attracting them. It has worked, too. Orchid species number more than 25, 000 worldwide, which is more kinds of species than any other flower on the planet, and new ones are still being found.
Orchids and the insects that pollinate them are one of the most amazing examples of evolution. By tricking the insects that collect its pollen, the orchid has survived since the time of the dinosaurs.
| Main points | Supporting details |
| Orchids are rare and delicate. | ●Orchid hunters consider their discovery of great . ●Many orchid hunters . their lives for special orchids. |
| Different types of orchids have different ways to spread pollen. | Pollination is a process where the pollen, containing the genetic material of the plant, is carried to the stigma of the flower, so that the plant can . ●Some species attract insects to land on their flowers with appearances to the insects. ●Some species what their pollinating insects want to kill. ●Some species their pollinator into mating with them so that the bugs can spread the pollen from flower to flower. ●than use their shape, other species produce special smells to attract specific pollinators. |
| The importance of the of orchids is great to scientific research. | Orchids and the insects that pollinate them are one of the most amazing examples. ●Orchids have the number of types among flowers on the planet. ●Nature has witnessed the of orchids since the time of the dinosaurs. |
