For example, an organism might have a chemical A that functions for some or no purpose. Chemical B might evolve independently of A and also function for some or no purpose. A mutation might occur putting these two chemicals together and now a more beneficial, dependent purpose is discovered. Those individuals with these two chemicals working together are now at an advantage for survival and would produce more offspring with the advantageous trait than those without the two chemicals working together. The new system would quickly become the norm.
Evolution can occur.
Also, learn how to use spell check. Yes I am doing a project for my class about the bombardier beetle. I was wondering do you have some pictures of this beetle. I wanna be able to have lots of pictures to show my class. Please send them to me.