Seahorses are beautiful and unusual fish that have captured the imagination of writers and artists for hundreds of years, and they feature in the ancient mythology (神话) and legends (传说) of many countries. Seahorses seem so magical that, to this very day, many people still believe they only exist in children's stories. But the fact is that these delicate and shy little creatures are very real!
Scientists believe seahorses evolved at least 40 million years ago, and have survived from ancient times with only very small changes in their body structure and function. Seahorses have a special appearance. They have a head like a horse, a pouch(育儿袋) like a kangaroo, and a long, curved tail like a monkey. Because of their confusing structure, for many years, people didn't know whether they were fish, insects or shellfish! Today, scientists know without a doubt that seahorses are fish.
Seahorses live mostly in shallow, warm waters. They are not strong swimmers, using only a back fin(鳍) and a pair of tiny fins behind their eyes to push them through the water. Seahorses spend a lot of time attaching to seaweed or sea grass. They are able to hang on to sea grass and seaweed by wrapping their tails around the stems, which helps them to avoid being swept away by strong currents. While they hang from sea grass, their long, tube-like mouth, which has no teeth, acts like a vacuum(吸管) for food. Strangely, seahorses have no stomach so they can't store their food. This means they have to eat fairly continuously throughout the day.
Another unique characteristic of seahorses is that they (along with their cousins, the pipefish) are the only creature in the animal kingdom where the male, not the female, becomes pregnant and gives birth to babies! The female produces eggs and places them in the pouch inside the male, where they are fertilized. The male gives birth to between 5 and 200 young. Amazingly, just a few hours after the male gives birth, the female will once again place eggs in the male's pouch.
Sadly, seahorses are in danger all over the world. Their habitats are being destroyed by human activities. People catch seahorses for pets and for souvenirs. The most endangered seahorse in the world is the Knysnaseahorse, which is only found in South Africa. The reason it is in grave danger is that it has an exceptionally limited distribution range—it is only found in three estuaries(河口) in the whole of South Africa. Unless these estuaries are conserved, South Africa will lose its only seahorse species for ever.
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Seahorses are fish with a peculiar appearance. They have a horse head, a pouch, along and curved tail. They live mostly in warm waters. They can't swim well so they attach themselves to seaweed or sea grass strong currents won't sweep them away. They eat most of the time because they have no stomach to store food. The male seahorse becomes pregnant and babies. Unfortunately, they're in danger because people catch them for . The Knysnaseahorse is in grave danger. If we don't protect it, it will be lost . |
