Herman Melvile, the writer of the famous whale story Moby Dick, once wrote that humpback whales were "the most lighthearted of all the whales." Known to be intelligent animals and can be seen working together to hunt schools of small fish, humpbacks are a favorite of whale watchers everywhere. And, if you listen closely, you might even hear one singing.

Marine (海洋) biologist Jim Darling has studied the songs of humpback whales for more than 25 years. While recording whale songs on a boat near Hawaii, he invited author Douglas Chadwick to experience diving with a humpback. In the water, Chadwick heard the whale's songs in a way he never heard them before. "Suddenly, I no longer heard the whale's voice in my ears," he said. "I felt it inside my head and bones." When swimming with the whale, Chadwick could see that the whale was aware of him, but not alarmed by his presence. Up in the boat, Darling recorded the whale's song, which can be long and complex, sometimes lasting for 30 minutes or more. Actually, they are perhaps the longest songs sung by any animal.

Darling says that only male humpbacks sing, but for unknown reasons, it was previously thought that they sang to attract females, but scientists showed this was incorrect when they played recordings of whale songs in the ocean and the female whales did not respond. Another idea is that male humpbacks compete with each other using songs, just as other male animals on land do using their horns or sharp teeth.

Researchers have also found that humpback whale songs are different in different parts of the world, perhaps like whale national songs. They may also be like hit tunes on the radio, changing over time—from one year to the next, or even over a single breeding season when they produce young.

Another member of the research team, photographer Flip Nicklin, recalls a special moment he had while interacting with a humpback. While he was snorkeling(潜水) some distance from the huge animal, it approached him until it was just a few metres away. It then gently carried Nicklin towards its eye with a flipper(鳍肢), as if examine him. Obviously, the urge to understand a different species goes both ways.

A wonderful experience happened to me this Saturday on my way to a mall. Two children ran towards mebottles in their hands，asking if I wanted to have bottled water. It was so （surprise）that I was unsure whether this was for real. I wondered if they （do）fund-raising. I asked them where（they）parents were and how much a bottle of water was. Then two adult women came to me and explained what the children were doing，"We are teaching the children （give）without getting anything in return."What a great idea!

 exchange of ideas opened up between me，the mothers and the children. We were no longer strangers to each other. We were having such a great time chatting. I felt very pleased，（end）up helping them give away the rest of the bottled water. 

One young lady was so （thank） that she said it was the best thing happened to her all day since she had a"bad"day at work. A couple accepted the water （happy）and kept on thanking us. After all was done，the children and I gave each other a high five. I really had great fun that day.

Olivia Ries was just seven years old when she and her eight-year-old brother Carter adopted a cheetah（猎豹） in South Africa. 

"When my sister and I first learned back in 2009 that species like the cheetah may be extinct in the wild by the time we have kids，it scared us. We knew we had to do something to help them，"says Carter. "There are so many people （young and old alike）who just don't know what is happening to so many species，just like we didn't. Olivia and I want to make sure we reach as many people around the world as possible and help them to understand how serious the situation really is."

To do that ， the kids started One More Generation（OMG），an organization with the motto："Preserving endangered species for one more generation and beyond."

Now，many years later，Olivia and Carter have traveled all over the world spreading their message. They've been interviewed on national television，participated in marches and fundraisers and won awards for their work. In 2015，they were invited to Vietnam by the United States Embassy to participate in a programme to save rhinos. All that they've accomplished for animals and the environment is much too long to list!

"Our number one message to everyone we meet is‘Remember，anyone can make a difference...if we can，you can too'，"says Olivia."We want all people to understand that what Carter and I are doing is not necessarily something special；it is something that we all should be doing. You can start small by simply adopting an animal. Do some research on the species you are interested in，and find a good organization offering adoptions. My brother and I take our birthday money and allowance money and adopt animals all the time. "