California is burning! Wildfires have spread across the US state since Oct 23 and smoke has filled its skies.

Take the Kincade Fire in northern California for example. It forced 200,000 people to escape(逃跑) its path within one week. The state’s largest power company cut power to about 206,000 homes in order to stop more fires from breaking out, CBS News reported.

California has seen many wildfires in recent years. Nine of the 10 biggest fires have happened since 2000, including five since 2010, according to The New York Times.

Why is this? California has the perfect wildfire conditions, Park Williams, a US climate expert (气候专家), told The New York Times. It has dry air and high temperatures from spring through late fall. At the same time, seasonal winds blow across the state every year, causing the wildfires to spread quickly and last for weeks.

Global warming has also made the fires worse in recent years. It has dried out the state’s trees and other plant life, causing them to burn more easily.

Humans have played a role as well. Burning campfires, garbage debris (垃圾碎片), and cigarette ends can easily cause wildfires. For example, one fire started last year when a car got a flat tire (漏了气的轮胎). The car’s body met the road and sent out sparks (火花), starting a fire.

Lightning strikes (雷击) and volcanic eruptions (火山爆发) can also cause wildfires. However, humans have caused 90 percent of California’s wildfires, according to the US National Park Service.

Wildfires often happen in wooded areas in the US, Canada and Australia. They are also known as forest fires or grass fires, or as bushfires (森林火灾) in Australia.

Wildfires can burn at over 900℃ and reach heights of more than 50 meters. They can move at speeds of up to 23 kilometers an hour, burning everything—trees, brush, homes, even people—in their path.

Dolphins are clever. It seems that they can think and learn things quickly. Studies show that dolphins and humans have something in common（共同的）. Let’s have a look.

Like humans, every dolphin has its “name”. The name is a special（特别的）whistle（口哨）. Each dolphin chooses a different whistle for itself, usually by its first birthday. Dolphins are like humans in other ways, too. They use sound and body language to “talk” with each other about a lot of things-such as their age, their feelings and finding food.

Dolphins live in groups. And they often join others from different groups to play games and have fun, just like humans. Playing together is something only clever animals can do.

Dolphins and humans are similar（相似的）in another way. Both of them make plans to get things they want. In the water of southern Brazil, for example, dolphins use a smart way to get food. When there are fish near a boat, dolphins signal to the fishermen to put their nets（网）in the water. In this way, the fishermen can get a lot of fish. Why do dolphins help the fishermen? That’s because they can eat some of the fish that run away from the net.

I was lying in bed, looking at a photo of Dahuang, a toucan (巨嘴鸟) living in a zoo. Although the photo was not bright anymore, Dahuang remained colorful in my mind. When I looked out of the window, a cherished (珍藏的) memory came back.．

Last winter, I heard a local zoo was in trouble because of the decrease (减少) in visitors. The zoo posted its condition on social media and asked for help. The zoo asked not only for food, but also people’s care for the animals. Dahuang was one of the animals in the zoo.

The news worried me a lot. Without thinking twice, I went to the zoo and gave away money to the zoo. That was the first time I had seen Dahuang. And I was always welcome to visit Dahuang. From then on, I have always sent things which Dahuang loved and Dahuang liked to play with me so much. The thing that Dahuang liked best was a toy bear. I received lots of photos of Dahuang playing with the toy bear from the zoo.

I printed my favorite photo of Dahuang and put it beside my bed. I was touched by this valuable photo and decided to keep a close eye on Dahuang and other animals in need. The unforgettable story between Dahuang and me was a cherished gift in my life.

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