Spatial (空间) learning is an important skill in the animal kingdom. This is because it helps animals find food when it’s not easily available. Insects such as bees and ants are known to do this.

A recent study has found that the butterfly also has ability of spatial learning. This butterfly comes from South and Central America. And it’s known for different types of wing patterns.

In the study, the research team carried out spatial learning experiments on butterflies under three different spatial conditions. First, they tested the insect’s ability to learn the location of real food in a 1-square-meter space made up of 16 fake (假的) flowers. This test represented (代表) searching for food in a single area.

________ And they tested if the butterflies could learn to connect food with either the left or right side of a 3-square-meter two-armed maze (迷宫), representing many plants at a single place.

The team then increased the distances again. They used large outdoor cages (笼子) to test if the butterflies could learn the location of food in a 60-meter-wide maze. This maze looks like the letter T. This test represented searching for food in the wild. This was closer to the conditions in which the insect finds food in the wild.

The experiments on butterflies show signs of spatial learning-they can remember the spatial location of their food. In the future studies, the team plans to test if they are better at spatial learning than closely-related species (近亲物种).

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Are you troubled by hangnails (倒刺) near your fingers? If you ever try to pull them, they really hurt. Why do we have more hangnails in winter?

Well, it turns out that our hands are drier during the season. The skin near our fingers isn’t so oily (油的) as the rest areas of our skin. Winter weather is usually dry, which takes away the little oil we have. When the skin is really dry, it becomes harder, giving us those painful hangnails.

Not having enough vitamins can play a part in having hangnails, ▲ . Still, it’s good to have foods rich in vitamins A and B, such as carrots, eggs, and fish, as Beijing Youth Daily suggests.

Don’t pull hangnails—it hurts, and it can make things worse by doing harm to your skin and causing more hangnails. Instead, you can put your hand in warm water for a few minutes and then cut the hangnails with nail scissors. You can also try using hand cream more often.

"The only constant (不变) in life is change. "Heraclitus said in about 500 B. C. That could be more true today.【小题1】 Technology is out of date almost by the time you buy it. We get plenty of information every day. Francis Bacon said. "Knowledge is power." In fact. There is more information in a newspaper than he would have experienced in his whole life.

Why are we afraid of change?【小题2】 After all, who knows what new dangers might appear? However, change is also the only way of development. Nobody can stop it in life. Luckily, our brains become stronger when meeting the unknown. 【小题3】 To be more imaginative and creative, you should look for and find environments you have no experience with.

【小题4】 For example, try a new restaurant, or go to a play or a concert you normally wouldn't attend. Small changes can help you gradually get used to uncertainty (不确定). So when bigger things happen. You'll be more fully prepared for them.

People who fear change often stick to a certain lifestyle. They believe they can control the future by doing so.【小题5】 If you can move from just accepting it to actively finding it out and dealing with it, you will be successful.