①Animal behavior（行为）is an interesting and attractive study. Scientists research the ways animals use to look for food. They study how animals protect themselves from their predators, and which animals kill other animals for food. All of this helps us understand how useful animals can be.

②Each country or culture raises some animals for food. In the United States, people mainly eat meat from cows, chickens and pigs. In other countries, people might raise sheep or buffalo for meat. These differences come in part from weather and other environmental conditions. People around the world eat all kinds of fish and shellfish from oceans and rivers. In some countries, people don’t always choose some animal groups, such as dogs, for food while in other countries such animals may become people’s favorite food.

③ In West Africa, animals provide humans with more than food. They have been helping people do daily work for thousands of years. Horses, oxen, and other work animals pull heavy things. Elephants; camels; and other animals carry people and things from place to place. Carrier pigeons（信鸽）have been used to send messages.

④People also receive health benefits’（利益）from animals. For example, dogs and cats can help calm people down. This is helpful for people fighting illnesses. Animals can also reduce stress, helping people to draw their attention to learning new information, such as reading. When people are walking their dogs or horses, it encourages exercise.

⑤Animals and humans share space on Earth, so keeping a healthy relationship with animals, around us is in our best interest.

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Imagine a world with no more wild animals: no elephants, no tigers or lions. To some people, that thought is too terrible for words. So they are doing something about it. Tiffany Soechting is one of them.

Being surrounded by wild animals—feeding them and caring for them—is all Tiffany Soechting has wanted to do with her life. And that is exactly what she does!

Soechting is the human “mother” to the 500 animals that live on her family wildlife farm in San Antonio, Texas. On the farm, she cares for animals from all over the world. Soechting says she loves them all. However, two reticulated giraffes(网纹长颈鹿) take up a special place in her heart. Their population in the wild has declined by 80% in the last 15 years. “I’m so glad to get help from five wildlife researchers that took giraffes up to a higher level. All our hard work helps protect giraffes living in the wild.”

Besides her animal caring, Soechtine also holds monthly classes: where she teaches school children about the animals.

Soechting also opens the farm to the public. Visitors not only learn about the animals, they can also get close to them. And the animals are not against that. For them, people are part of their natural environment.

The farm is part conservation(保护) area, part educational center and part animal park. As the animals walk peacefully around the grounds, it is easy to forget that San Antonio, a busy city, is just a few minutes away.

When we look at animals, we know that they are not humans. But how do our closest friends dogs see us? Do they know that we are humans? Or do they actually think that we are just strange- looking dogs?

You may be surprised to know that many kinds of animals do not notice such differences very much at all. For example, the cuckoo (布谷鸟) lays its eggs in the nest of another bird. These birds will feed the baby cuckoos, even though they look nothing like their real babies. This is because the birds feed in an instinctive (本能的) ways.

Other animals, it seems, will simply separate the world into animals they eat, and animals that eat them. When it comes to dogs, though, there is no simple answer to this question.

Sheepdogs leave their mothers when they are born. They grow up with sheep, and come to see them as their family. For this reason, they never attack the sheep, and help protect them, they probably think the sheep are dogs too, but we can’t be certain.

Similarly, if you keep a dog from birth, the way it sees the world will be different to a dog that grows up with other dogs. It will probably think it is the same kind of animal as you. This can even be true of humans. A Russian boy called Ivan Mishukov, born in 1998, was raised by dogs for two years and came to believe that he was a dog himself.