I was really impressed evolution of mammals and reptiles such as dinosaurs in Seodaemun Museum of Natural history. Especially,  the word 'life' made me think carefully. 

There are many people who claim that other creature's pain or hurt can be no problem if  it's purpose is human's developing. However that' s the problem. Every creature breathes on its own way. all creatures sleep, eat, say and undergo everything that human undergo.  Of course all the people say that they can't feel or think. However the point is that we cannot understand or communicate with them. Giving them pain for our developing is similar with giving someone a right to kill other people. Even though we are really smart or strong, we are not God.  Nobody can mke decision that make other creature die. Even though someone did it, it's wrong decision.

In French novel 'The Ant' there are words enough to make us wise.

"You know why humans are strongest animal? They respect and help other creature