jiffy man, i started thinking about this stuff about a year a two ago. The more and more i thought about it, and the more biology/religion classes i took. It seemed to be more clear what i believe.
Im takin an intro to religion class right now, for the same reason you are asking these questions.
you said
"but its been done so long no one bothers to ? it and see if its right"
People have been questioning this for years and years and years. But what makes most people think is the battle that happend not to long ago,
science vs. religion. Galileo was condemed by the church when he made the discovery that everything revolved around the sun instead of the earth. They made him take it back and say he was wrong.
What most people also don't know is that islam, muslim and christianity are all based on the same God, but yet they are constantly at war with each other. If people would wake up and realize whats going on, they might become smarter and stop this foolish stuff. I dont think i answered your questions, but i just wanted to reply.
And im sorry if I offended anyone.