In ancient China, birds are trained to carry letters, and science then animals are trained to help human beings. Nowadays, trained animals are wide used in many areas such as searching for survivors after an earthquake, finding the hiding drugs and guide the blind.
Some argue that man should not train animals and use them as a tool, it’s just too cruel to them, instead, man should take good care of them, feed them as well as protect them. That sounds kind of ridiculous, anyway, man is not GOD who is omnipotent and protect everything. Of course, the best way to treat the animals is to let them free in nature and not disturbing them. But as a result of the development of human civilization, the habitats of animals have been effected, and some animals have been taken into man’s society, such as dog. They are usually trained as a door-keeper and treated as a family member.
Think about the fact that there are hundreds of homeless animals roved around the city and many of them have been maltreat by man or even their “ex-owner”. Why is the so? Because these man just raise the little animals for fun, and when they get bored, the life of these little creatures will be at risk. Now think about the trained animals in another way, will you abandon your door-keeper or your guide dog when you get bored with it? Absolutely not! Because they are useful! As a matter of fact, a trained animal are often regarded as a friend or a family member and they are treated better than those animals which just be bought as pet in the long term.
Or you can think about it in a more humorous way, which one do you think probably have a good life, a trained man or a tramp?