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    Many people think the camel stores water in its hump (驼峰), but it does not. Instead, the camel stores something else there—food. The camel's hump is really a hump of fat (脂肪). The camel is often called "a ship of the desert". When the camel is not travelling and is in a place where there is much food and water, it eats and drinks a lot. As it does so, its hump rises from the fat its body makes. Then, when the camel is travelling through the desert and when there is no food, it can live off the stored fat.

    A camel can go on for days or weeks with little food or water. However, when its hunger reaches the starvation (饿死)point, its hump shrinks (收缩) and may even slip off its back and hang down its side.

    Camels are not fussy (挑剔的) about what they eat. Thorny (多刺的) plants don't hurt their mouths, grass of any kind will do and so will hay, dry grain and cactuses (干草, 干粮, 仙人掌).

There are one­ hump camels and two­ hump camels. Camels with one hump are called Arabian camels. They come from North Africa. Camels with two humps are from Asia.

    It is a question that has confused parents for many years: why do children refuse to eat greens?

    Now, two American experts believe they have the answer.

    After studying dozens of babies as they played with various objects, the researchers noted that they were far more unwilling to touch plants than other things. They believe this is because evolution (生物进化) has biologically made children be wary of plants.

    Due to susceptibility (敏感性) to illness or injury in the early years of life, the body has designed an inner defence mechanism (内部保护机制) that limits a child' s contact with plants, they think. The researchers believe this is why children turn their noses up when faced with a plate of broad beans.

    The findings are published in a paper by Dr Annie E Wertz and Dr Karen Wynn, both psychologists at Yale University.

    They wrote, "Throughout human evolution... plants have been important in human's life. Yet, for all of these benefits, plants have always caused very real dangers."

    "Plants produce toxins (毒素) as defences that can be harmful, or even deadly. Some plants also produce physical defences, such as thorns（荆棘）can damage tissues (组织) and cause effects over the whole body."

    They added, "We predicted that babies may have behavioural strategies that reduce dangers caused by plants."

    To test their theory, the researchers studied how children aged eight to 18 months old reacted when presented with a variety of objects. It took much longer for children to grab plants; objects that were pretended to look like plants also caused a slow response time.

    For parents attempting to spoon some peas into the mouth of their child, this finding should come as welcome relief.

    The spring season brings warm weather, flowers and other changes for people to enjoy. For some restaurant cooks, the most exciting spring arrival is ramps.

    Ramps are a wild plant in the eastern mountains of North America. They are one of the first plants that grow in the spring, usually between April and May. They are recognized(意识) by their red stem(茎), and two long and wide green leaves. They are also famous for their strong taste, similar to onions(洋葱).

    Ramps are not as well-known as other vegetables, but they have a long history in the United States. In the Appalachian Mountains, ramps have been an important food for a longtime. During spring, it is common for small towns in the Appalachian area to hold large ramp dinners for the community.

    However, over the last 30 years, ramps popularity has grown quickly. They are now a highly-desired vegetable for many nice restaurants in cities like New York and Washington D.C.

    One reason the plant is popular is that it grows in the wild. It is difficult to grow them on farms. Most restaurants get them from foragers, who collect ramps by searching forests for some small pieces of land where they grow. Ramps have a short season. Within a few weeks of full growth, the plant is done for the year. This shot life is some reason for their popularity.

    And that popularity could lead Io their disappearance from Earth. In 1995, the local government in Quebee, Canada, stopped people selling the plant to businesses in order to protect the plant against being over-dug.

    The season is short, but it has not ended yet. If you are in the right place, you still have time to try a taste of ramps yourself.

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